B14 motor musings...

[blackshire]

Hello All,

While I don't expect B14 motors to make a comeback, I am curious about the details of how they were produced. This could shed light on possible new B14 production.

Were their propellant grain voids drilled out manually or by some kind of automated system? In any event, this last production step was probably less dangerous than the initial propellant grain/delay charge/ejection charge pressing operation because the (initially) loose black powder involved could have set off the entire loose powder batch in the motor production building if it had ignited. A B14 that ignited during the later void drilling step would probably have affected only that particular motor and the drill.

It would seem that an automated system (especially using today's technology) could drill out B14 propellant grain voids safely. The costs of developing such a system could, of course, make the production of new B14 motors economically non-viable, especially for making small quantities of the motors. But if the production quantities were large enough (whatever that number might be), they would be worthwhile to produce.

[LeeR]

I visited Estes Industries when I was a kid (in 1966), and remember the fantastic tour, including seeing Mabel cranking out engines. I also remember someone performing an operation on motors, and believe it was drilling out B14s. It was a long time ago, so I could be wrong. But, I am not sure why they would have to be drilled. Why not an automated process that has a pin that rises up into the nozzle prior to pressing the BP, and then is extracted, leaving a core?

I still have a few Estes B14s, and quite a few Centuri B14s, so I may try one of each this summer. I loved that motor as a kid! Only one problem I ever had -- I launched a Flying Jenny biplane glider with one, and it suffered major balsa disintegration.

[Doug Sams]

But, I am not sure why they would have to be drilled. Why not an automated process that has a pin that rises up into the nozzle prior to pressing the BP, and then is extracted, leaving a core?I think that's essentially the B8/C5.

My take is that for the more aggressive (steep) core of the B14, if you tried to merely ram it, that you wouldn't get the powder to pack tightly around the pintle (I think that's the right term) with the result that the core wouldn't be formed properly.

Since it's a powder being rammed (and not a liquid), you don't get true hydraulic behavior so the vertical pressures in the casing during the ram are greater than the horizontal forces - there's not enough force to pack the powder tightly around the core.

Anyway, that's only my theory - I am not a motor manufacturing expert - IANAMME :)

Doug

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[tbzep]

I think that's essentially the B8/C5.

My take is that for the more aggressive (steep) core of the B14, if you tried to merely ram it, that you wouldn't get the powder to pack tightly around the pintle (I think that's the right term) with the result that the core wouldn't be formed properly.

Since it's a powder being rammed (and not a liquid), you don't get true hydraulic behavior so the vertical pressures in the casing during the ram are greater than the horizontal forces - there's not enough force to pack the powder tightly around the core.

Anyway, that's only my theory - I am not a motor manufacturing expert - IANAMME :)

Doug

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It would also have to be a longer and more fragile pintle, and they would likely be broken or bent often.

[blackshire]

It would also have to be a longer and more fragile pintle, and they would likely be broken or bent often.I believe the old Teleflite book on "roll your own" black powder model rocket motors also touched upon this issue regarding core-burning motors.

From LeeR's recollection (I wish *I* could honestly wear a "I Toured the Estes Plant and Didn't Get Blown Up!" T-shirt!), it sounds like the B14 motors were manually drilled out. An automated system using a "magazine" feeder and a relatively slow drill (with a non-ferrous metal bit) could drill out B14 motors, and the leftover black powder drill "dregs" might even be reusable (if they could be safely "re-powdered" to the required mesh size) for propellant grains in other motors.

[GregGleason]

I wonder why a binder couldn't be added so that it could be held together? Or some kind of "Swiss cheese" plastic form to hold the void, while it sits upon a form-fitted metal mandrel (of a suitable material) so that the two work together as the BP is pressed into the motor, but that the plastic part stays with the motor.

Greg

[stefanj]

I really doubt the process was "manual," in the sense of a guy with a Ryobi taking careful aim down the nozzle. I'm sure there was a hopper and a jig to hold the motor in place and an automated drill, as Blackshire suggested.

Some little clues:

There's a late-60ish Model Rocket News article giving a tour of the factory. There's an overhead shot of the plant.

The accompanying text says, paraphrasing: "Series II and III motors are brought to building X for further processing."

Series II motors are B14s. Series III are shorties.

Chances are the shorties started out with normal sized casings and were cut short. Easier than making a new Mabel to accomodate the shorter casing.

[blackshire]

I really doubt the process was "manual," in the sense of a guy with a Ryobi taking careful aim down the nozzle. I'm sure there was a hopper and a jig to hold the motor in place and an automated drill, as Blackshire suggested.In those days, it was probably a Sears Craftsman or a Black & Decker drill... :-)Some little clues:

There's a late-60ish Model Rocket News article giving a tour of the factory. There's an overhead shot of the plant.

The accompanying text says, paraphrasing: "Series II and III motors are brought to building X for further processing."Interesting...was this building as far away from the main plant as the motor production buildings? (If it was closer, that suggests that the B14 drilling step and the Series III "case chopping" step weren't considered as hazardous as motor filling operations.)Series II motors are B14s. Series III are shorties.

Chances are the shorties started out with normal sized casings and were cut short. Easier than making a new Mabel to accomodate the shorter casing.I don't know one way or the other, but the statement in the article text certainly suggests that. If that was the case, what (if anything) might Estes have done with the cut-off excess lengths of motor casings? They weren't ones to waste materials. If nothing else, it would seem that 1/8" or 1/4" thick rings cut from the "waste" motor casing pieces could have been used as heavy-duty BT-20 thrust rings for high-thrust motors such as the B14.

[blackshire]

I think that's essentially the B8/C5.

My take is that for the more aggressive (steep) core of the B14, if you tried to merely ram it, that you wouldn't get the powder to pack tightly around the pintle (I think that's the right term) with the result that the core wouldn't be formed properly.Yes, that's the most common term (pintle) for it that I've encountered, although in the book "All About Rockets & Jets" by Fletcher Pratt, the section that describes and illustrates Skyrocket motor pressing calls it a "thorn."Since it's a powder being rammed (and not a liquid), you don't get true hydraulic behavior so the vertical pressures in the casing during the ram are greater than the horizontal forces - there's not enough force to pack the powder tightly around the core.Indeed--up to a point, as long as it is tapered and not cylindrical (as was the pintle used in the B8 & C5 motors, as well as the conical thorn often used for pressing skyrocket motors), the pintle or thorn can apply sufficient vertical (bottom-to-top) pressure to the black powder grains to force them together into a solid mass when the grain is pressed.

[jdbectec]

I believe the old Teleflite book on "roll your own" black powder model rocket motors also touched upon this issue regarding core-burning motors.

From LeeR's recollection (I wish *I* could honestly wear a "I Toured the Estes Plant and Didn't Get Blown Up!" T-shirt!), it sounds like the B14 motors were manually drilled out. An automated system using a "magazine" feeder and a relatively slow drill (with a non-ferrous metal bit) could drill out B14 motors, and the leftover black powder drill "dregs" might even be reusable (if they could be safely "re-powdered" to the required mesh size) for propellant grains in other motors.


While I can't comment directly on the B14, Lee Piester told me the old Mini'Max core burners were drilled, IIRC, using some kind of fixture and a horizontal boring machine. He also mentioned one would occasionally ignite! This prompted the move to Enerjet composite motors, much safer.

Using a pintel requires more than one ramming head, no big deal using the Teleflight methods, but not suitable for "Mable" type machines.

Terry Dean or Fred Schecter should chime in, as they are more knowledgable about this than I.

For the record, I BELIEVE, some type of binder is used in BP motors to ensure they form a good grain, something I remember from a MSDS(?) I read.

Of course I'm no expert either, and I could be wrong about all of this, I've been wrong before.

[blackshire]

Yes, the manual hand-rammed methods in the Teleflite book could be rather involved. I was put off trying them by the first step given in the book, which was the construction of a steel plate "explosion shield."

Sugar rockets aren't quite as hazardous to make as black powder motors, and they lend themselves to core-burner grains. (It's really a necessity with sugar motors due to the propellant's lower specific impulse.)

[Bazookadale]

For the record, I BELIEVE, some type of binder is used in BP motors to ensure they form a good grain, something I remember from a MSDS(?) I read.

Of course I'm no expert either, and I could be wrong about all of this, I've been wrong before.

The sulfur in the BP acts as a binder, but the MSDS I found with a case of motors indicated that a small amount of dextrin was added which would also be a binder

I have also been wrong in the past - once in 1973 and again in 1994!

[Ltvscout]

We do have an expert on the subject that has firsthand knowledge on making Estes engines that is a regular here on YORF. Maybe one day he'll speak up and shed some light on our many motor questions. ;) (Note I used engine and motor in the same paragraph. heh)

Anyhow, he may also have signed some agreeement when he retired that does not allow him to speak about the manufacturing process for all I know.

[jdbectec]

The sulfur in the BP acts as a binder, but the MSDS I found with a case of motors indicated that a small amount of dextrin was added which would also be a binder

I have also been wrong in the past - once in 1973 and again in 1994!

Yes, I believe it was dextrin, I can't seem to find the pdf I had of that. A Google search shows that it is used as a binder in pyrotechnics.

[jdbectec]

Yes, the manual hand-rammed methods in the Teleflite book could be rather involved. I was put off trying them by the first step given in the book, which was the construction of a steel plate "explosion shield."

Sugar rockets aren't quite as hazardous to make as black powder motors, and they lend themselves to core-burner grains. (It's really a necessity with sugar motors due to the propellant's lower specific impulse.)


The blast shield did discourage me from trying it my attached Garage!

Not that I could think of anyway to do it safely, other than the way it's done by manufacturers.

[shockwaveriderz]

There is a thread or threads here on YORF in which we all contributed real or perceived manufacturing methods for the original original b16-b3-b14 and the later variations of the B14 to B8 transition, along with historical info and pics.


What follows is from memory and email conversations but the "O-O" b16-b3-b14 was actually just a B4 which has a wider core than a B6 that then had an approx. .25-.375 length cylinder shaped smaller core in it. If you look at the old Estes catalogs you will see pics of elongated cores running 3/4 "of the way up the grain; this was misinformation primarily to fool potential rival companies from copying Estes trade secrets.

So the "O-O" B14 started our life on a Mabel as a B4 and was then drilled by a machine designed invented by Vern Estes. I'm not at liberty to go into the exacting details of the size and type of drill used,etc. Let's just say it wasn't simply just a twist drill. Vern did numerous tests varying drill bit types and rpm's to get the "sweet spot"....

So the "O-O" b14 was a semi-automated 2 step process.....


This 2 step process resulted in periodic explosive events so later B14's that evolved into the B8's later were all made from fully formed mandrels in Mabels.

I think "O-O" B14 could probably be made to day fully automated, using a combo cylinder-coned shaped mandrel, but if that was true Estes probably would have already done it.

I've never been privy to how abrasive the hydraulically pressed fine black powder is on the tooling.....but i'm sure it has to be replaced or retrofitted on a more or less regular basis as the fine black powder being pressed at the pressures they are on automated runs over time had to be very abrasive, so the tooling has to be made of some pretty hard stuff.

I would guess for insurance purposes they have made the business decision to let B14's Rest In Peace.

hth

Terry Dean

[ghrocketman]

I personally have original examples of late 60's/early 70's Centuri B14-7's and Estes B14-0's that have cores so narrow that they MUST have been drilled. Any pintle that deep and small in diameter would most likely break under the ramming pressure.
The drilled core is approximately .0625 (1/16") in diameter and quite deep. The nozzle appears to be a standard "B4" profile nozzle diameter and shape.

[jdbectec]

Thanks for chiming in Terry. Your post confirms my suspicions. Maybe we will see a B8-x again some day, or a C5-0, but I think B14's are gone but not forgotten.

[shockwaveriderz]

The sulfur in the BP acts as a binder, but the MSDS I found with a case of motors indicated that a small amount of dextrin was added which would also be a binder

I have also been wrong in the past - once in 1973 and again in 1994!


Sulfur does not act as a "binder" in EstesBP rocket engines. There is no need for an additive binder in Estes BP engines, because they press to approx 1.7 g/cc ..at these pressures the fine particles of black powder ie KNO3/S/C undergo a plastic deformation process...ie they become somewhat plasticized and they flow freely into and with one another.

http://en.wikipedia.org/wiki/Plasticity_%28physics%29

Sulfur does act as a pyrolant in black powder ie as an ignition promoter.




As far as Dextrin being used in Estes engines, I too have seen that MSDS..... I once asked a source if Dextrin was every used in the Estes manufacturing process as a binder or anything else..... and I was told no. It may show up on the that old MSDS because it was used a a burn rate modifier in the delay train...... but it was not used in the actual propellant.

If you look at modern day MSDS from the 80's forward you will see no mention of dextrin. Dextrin is a well know binder used by some who make BP pyrotechnic skyrockets. It will also slow down the burn rate. This is favorable in skyrockets as they are have full top to bottom cores and a slower BP is required.



It is my understanding the the large FGH Rocketflite BP engines actually used a water based elastomer as a binder but this was required because of their sheer size and their large cores.... the binder made the pressed BP grains somewhat rubbery so they wouldn't crack and they would adhere better to the casings.

HTH

Terry Dean

[jdbectec]

I personally have original examples of late 60's/early 70's Centuri B14-7's and Estes B14-0's that have cores so narrow that they MUST have been drilled.


Now that we know all about B14's, and have a good idea on the Mini-Max's, Does anyone know how FSI cored/pressed their motors?

[ghrocketman]

FSI F100 and E60 motors were pressed around a large-diameter pintle.
Not sure about the D18 and D20 though as those cores were MUCH smaller.

[Shreadvector]

Now that we know all about B14's, and have a good idea on the Mini-Max's, Does anyone know how FSI cored/pressed their motors?

I don't know for sure, but I know they had at least 7 rammings in the F7 and F100. They added some propellant and rammed it in, then repeated until they were done.

[Doug Sams]

The nozzle appears to be a standard "B4" profile nozzle diameter and shape.I have seen some later B14's that looked more like B8's - they didn't begin to have the larger cores seen on the earlier B14's. It wasn't clear to me if this was due to worn out drills, substitution (ie, selling B8's as B14's before finally getting new cert's and name changes), or mislabelling.

(I posted a pic of the various B14 and B8 nozzles somewhere, but danged if I can find it now...) [Edit: It was on my old website, but I need to upload it to my new one.]

Doug

.

[tbzep]

I don't know for sure, but I know they had at least 7 rammings in the F7 and F100. They added some propellant and rammed it in, then repeated until they were done.

IIRC, that's the way some of the Chinese motors were done, creating a pulsing thrust. I havn't flown my D5's or long burn C6's yet, so I'm only going by memory of what has been posted here in the past.

[Shreadvector]

I have seen some later B14's that looked more like B8's - they didn't begin to have the larger cores seen on the earlier B14's. It wasn't clear to me if this was due to worn out drills, substitution (ie, selling B8's as B14's before finally getting new cert's and name changes), or mislabelling.

(I posted a pic of the various B14 and B8 nozzles somewhere, but danged if I can find it now...) [Edit: It was on my old website, but I need to upload it to my new one.]

Doug

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I think there was a later (possibly Centuri blue or green casing era) version of B14 make with a deep tapered core rather than the core with two steps seen earlier. It was much deeper than the B8/C5 core.

[blackshire]

I think there was a later (possibly Centuri blue or green casing era) version of B14 make with a deep tapered core rather than the core with two steps seen earlier. It was much deeper than the B8/C5 core.I have one of those blue-casing motors (a Centuri B14-7, Date Code: 110 1 73). Its nozzle is *very* wide and is almost cylindrical in cross-section, rather like the "nozz-hole" orifices in the Quest MicroMaxx motors. The tapered propellant grain void looks conical (it may be cylindrical for the upper 20% or so, but the foreshortened view makes it difficult to tell).

I also have an Estes B14-5 (Date Code: 21J5), whose nozzle looks like a B4's nozzle (going from memory, as I don't have any B4 motors on hand). The nozzle is considerably narrower than the Centuri B14-7's nozzle; it is a straight-sided cone that narrows down to a short cylindrical section. The grain void beyond is almost cylindrical, being a gently-tapered cone.

For comparison, a Centuri B8-5 I have (Date Code: 10l8? [the bottom of the third character wasn't printed]) has a nozzle only slightly wider than that of an Estes B6-4 (Date Code: 10 A 10). The grain void is conical, with perhaps the upper 10% - 15% being cylindrical.

[Doug Sams]

(I posted a pic of the various B14 and B8 nozzles somewhere, but danged if I can find it now...) [Edit: It was on my old website, but I need to upload it to my new one.]Here it is: (The dimensions are nozzle depth.)
http://www.doug79.com/motors/B14-vs-B8-3.jpg

And here's a close-up:
http://www.doug79.com/motors/B8-B14-closeup-p.jpg


Doug

.

[blackshire]

Thank you for posting these pix, Doug!

[ghrocketman]

I think the right most B14's in those pics are the "precursors" to the B8 motors that replaced them.
Functionally, those last produced "B14s" I theorize were actually B8's; I have some late B14-7's and I cannot tell ANY dimensional difference in them from the B8-7's from a year later even under magnified examination.

[Shreadvector]

I think the right most B14's in those pics are the "precursors" to the B8 motors that replaced them.
Functionally, those last produced "B14s" I theorize were actually B8's; I have some late B14-7's and I cannot tell ANY dimensional difference in them from the B8-7's from a year later even under magnified examination.

here is a theory (based on nothing but a guess):

Motor manufacturers can change a design without recertification as long as there is no major change. Often a motor is redesigned because of a change in propellant (different sources of black powder) or a change in place of manufacture. Usually the new samples are submitted for recertification, sometimes with the same motor designation (like the Quest C6-5 made in USA, Germany and China). back in the 1970's they may have tweaked the B14 design and tried to keep calling them B14's, but then either decided to recertify them as B8 on their own or after the NAR told them to do so.

I still think there was a tapered bore version (deep large hole plus deeper tiny drilled cylinder) as well as a long tapered single bore version (like a B8 bore, but deeper).

Any photos or measurements of a 196's era English units B3 motor?

8.1.6 Any changes exceeding manufacturing tolerances

made to the physical design or chemical composition of a

model rocket motor, motor reloading kit, or component(s)

by a manufacturer after certification testing shall be reported

to the recognized testing organization that originally

granted the certification prior to sale or shipment. If

the changes potentially affect characteristics measured in

the original certification testing, that testing organization

shall be permitted to require that samples of the changed

product be submitted for testing.

[Doug Sams]

I think the right most B14's in those pics are the "precursors" to the B8 motors that replaced them.
Functionally, those last produced "B14s" I theorize were actually B8's; I have some late B14-7's and I cannot tell ANY dimensional difference in them from the B8-7's from a year later even under magnified examination.That's kinda how I'm thinking, too.

But note one key diff: The narrow bore B14, which looks much like the B8, is still deeper, 0.75" versus 0.6". It has the same depth as the bigger bore B14's.

OTOH, it could simply be the later B14 (in the pic) was formed on a pintle that had been worn down (eroded) by too many pressings, and then drilled. Or maybe the drill bit itself, assuming a two slope drill bit, had been worn down by too many drillings. (A bit with a long, narrow tip that also includes a wider cutter up the shank, sort of a like a bit in a countersinking mount, could be used to simultaneously drill the deep, narrow core while also widening and reshaping the nozzle. Such as bit could wear faster on the abrasive clay end thus resulting in the smaller nozzle openings while still maintaining the deep bore.)

But I like the precursor idea better :)

Doug

.

[shockwaveriderz]

http://www.forums.rocketshoppe.com/attachment.php?attachmentid=10757

3 b3- rocket engine cores from 1967 by SEL



also found this:

http://www.forums.rocketshoppe.com/showpost.php?p=51154&postcount=62


the B.8 (old designation) was of course a B4 (new designation) Although MMI sold at as a B6......


Terry Dean

[Shreadvector]

I find that picture to be very Hypnotoad-esque.

:D


http://www.forums.rocketshoppe.com/attachment.php?attachmentid=10757

3 b3- rocket engine cores from 1967 by SEL



also found this:

http://www.forums.rocketshoppe.com/showpost.php?p=51154&postcount=62


the B.8 (old designation) was of course a B4 (new designation) Although MMI sold at as a B6......


Terry Dean

[ghrocketman]

My early B14 engines from '68 or '69 look almost exactly like those B3 nozzles that OBVIOUSLY have drilled cores.

[Doug Sams]

My early B14 engines from '68 or '69 look almost exactly like those B3 nozzles that OBVIOUSLY have drilled cores.They should. As I understand it, the only difference between the B14 and the B3 was the metric versus imperial units designation. 3*4.45~=14. At some point, the thin walled casings took over. Not sure how that may have affected things. But if the ID of the case is greater, then less depth of BP is needed to achieve the same volume of BP (~equating volume with impulse). So I wonder if the core had to be revamped somewhat to deal with that, to keep from breaking/burning thru too soon.

Doug

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[Shreadvector]

They should. As I understand it, the only difference between the B14 and the B3 was the metric versus imperial units designation. 3*4.45~=14. At some point, the thin walled casings took over. Not sure how that may have affected things. But if the ID of the case is greater, then less depth of BP is needed to achieve the same volume of BP (~equating volume with impulse). So I wonder if the core had to be revamped somewhat to deal with that, to keep from breaking/burning thru too soon.

Doug

.

I had B3 motors with the thick walled casing (same as used in the classic 1/4A3, 1/2A6, A5 and B4 18mm motors). I flew them. They worked.

[Gus]

Guys,

Can you give me an example of what you might have flown on a B14-7. I always think of the B14 as a heavy lift motor and I'm having trouble reconciling that with a 7 second delay.

[Royatl]

Guys,

Can you give me an example of what you might have flown on a B14-7. I always think of the B14 as a heavy lift motor and I'm having trouble reconciling that with a 7 second delay.

Estes recommended it as an upper-stage engine for the Apogee II, and the Delta when lifting the Camroc. For the Farside and Farside-X, they recommended the -6. Yes, they made a -5, -6, and -7!

Centuri was a bit more liberal in recommending the B14-7 for its kits, listing it for their small, ST-7 (like Javelin) or ST-8 (like MX774) kits, but *not* for their multistagers!

[shockwaveriderz]

Guys,

Can you give me an example of what you might have flown on a B14-7. I always think of the B14 as a heavy lift motor and I'm having trouble reconciling that with a 7 second delay.


This is an interesting question, Gus. I can remember in my first go-round with modle rocketry circa 1967-1972, that I had B14 motors........ But I really don't have any memories of actually using any. I was not (and still am not) a very good modeler, and once I figured that out (which was within the first 2-3 kits), I basically just read the Model Rocketry magazine and collected kits and engines at NARAM-12 and NARAm-13. I know for sure that I spent at least $500 each visit and brought a lot of stuff back but never built it and it sat in a strage shed until the late 70's or early 80's when my mom moved and threw it all away. She did keep the MR magazined and gave them to me years later.

In the 7th grade we had a rocketry "club: that consisted of a few people in the overall science club, and my neighborhood friends only came around to watch me launch and chase my rockets. They pushed the button sometimes but that was about it. There was no local hobby stores as I lived in a small rural town (pop. maybe 3,000) so I was basicially a lone rocketeer as a kid from 12-16.

Sorry to get carried away. I know from my memory that I had 2 rnage boxes stocked full of modle rocket engines of all types purcahsed between 67-72... I would estaimate at least several hundred easily.

Terry Dean

[Bazookadale]

Estes recommended it as an upper-stage engine for the Apogee II, and the Delta when lifting the Camroc. For the Farside and Farside-X, they recommended the -6. Yes, they made a -5, -6, and -7!

Centuri was a bit more liberal in recommending the B14-7 for its kits, listing it for their small, ST-7 (like Javelin) or ST-8 (like MX774) kits, but *not* for their multistagers!


I flew the old B3-7 in my Centuri Javelin - what a neck snapper! Maybe that is the cause of the arthritis in my neck today :mad:

[blackshire]

Estes recommended it as an upper-stage engine for the Apogee II, and the Delta when lifting the Camroc. For the Farside and Farside-X, they recommended the -6. Yes, they made a -5, -6, and -7!

Centuri was a bit more liberal in recommending the B14-7 for its kits, listing it for their small, ST-7 (like Javelin) or ST-8 (like MX774) kits, but *not* for their multistagers!For a Javelin or an MX-774, the B14-7 would certainly be a brute-force way to get the model up to maximum velocity (certainly much more quickly than from the relatively long, gentle push from a B6), but it would probably reduce weathercocking and dispersion due to the wind. Still, what a blur that must be at liftoff!

[Ltvscout]

Can you give me an example of what you might have flown on a B14-7. I always think of the B14 as a heavy lift motor and I'm having trouble reconciling that with a 7 second delay.
Works great with an Estes Sprint.

[Jerry Irvine]

Has anyone publicly documented the core diameters, lengths, and draft angles for the various versions, so some day in the future these motors can be duplicated and re-released by some motivated guy with a mini-Mabel in his barn?

There are guys making Polaroid film again. It could happen.

Jerry

[LeeR]

I did an inventory of old motors, and found a number of B14s -- both Estes and Centuri, from 1969 and 1970. I thought I'd made a mistake logging the inventory, and having an entry for a B14-6. I guess I didn't realize there were three variations, with only 1 second difference in delay. All are just loosely bagged, but have been in my basement since the early 80s, so I'm pretty confident these could be OK, and plan to test a B14-0 soon.

The Centuri motors I bought were boxed, and have date code J, which should be 1979, assuming these are Estes-manufactured. My 1969 Estes and Centuri motors have identical "inkings", and differ only in company name and address. I got these boxed motors as seen here, included in the orange, white, and blue display box that contained the smaller, similarly colored 3-packs. I was fortunate to get 2 boxes of B14-0, and 1 box of C5-3S, would have loved to stumble on a full box. Some pics:


http://i265.photobucket.com/albums/ii220/hobbes_pics/Centuri/th_centuri-02.jpg (http://s265.photobucket.com/albums/ii220/hobbes_pics/Centuri/?action=view&current=centuri-02.jpg)http://i265.photobucket.com/albums/ii220/hobbes_pics/Centuri/th_centuri-01.jpg (http://s265.photobucket.com/albums/ii220/hobbes_pics/Centuri/?action=view&current=centuri-01.jpg)http://i265.photobucket.com/albums/ii220/hobbes_pics/Centuri/th_centuri-03.jpg (http://s265.photobucket.com/albums/ii220/hobbes_pics/Centuri/?action=view&current=centuri-03.jpg)http://i265.photobucket.com/albums/ii220/hobbes_pics/Centuri/th_centuri-04.jpg (http://s265.photobucket.com/albums/ii220/hobbes_pics/Centuri/?action=view&current=centuri-04.jpg)

[Ltvscout]

I did an inventory of old motors, and found a number of B14s -- both Estes and Centuri, from 1969 and 1970. I thought I'd made a mistake logging the inventory, and having an entry for a B14-6. I guess I didn't realize there were three variations, with only 1 second difference in delay. All are just loosely bagged, but have been in my basement since the early 80s, so I'm pretty confident these could be OK, and plan to test a B14-0 soon.
Back around 2000 there was an online hobby store, I don't recall the name, that had come across a huge stash of NOS Centuri motors. The majority of them were in the old orange/black/white boxes. One of the motor types they had were B14-6 motors. Amazingly, they were selling these old motors extremely cheap. I bought a ton of motors from them at the time and still have them sitting in storage.

I believe they got their motors from the same warehouse where John Boren got his stash of cases of old Centuri motors.

Addendum: Now that I think about it I believe it was A2Z Hobbies that had the old motors.

[Doug Sams]

I believe they got their motors from the same warehouse where John Boren got his stash of cases of old Centuri motors.Scott Hunsicker's garage? :D

Doug

.

[Ltvscout]

Scott Hunsicker's garage? :D

Heh, no. I believe it was some old hobby warehouse somewhere in IN.

[ghrocketman]

As Scott mentioned, one of the best rockets to use the B14-7 in single-stage is the Astron Sprint. I have probably used that engine in the Sprint more than any other. I often used it in the top stage of my Astron Avenger and my Comanche 3.

[UCBadger]

Many years ago, when I started flying rockets, around 1970, I really liked two stage rockets. Back then you could get boosters in A, B, C and even shorties. The sight and sound of the staging was really cool. I had a rather large (for Estes) two stage rocket that would stage around 100 feet or more when the first stage was a C engine. When a B14-0 was used it really zipped off the pad and staged just past the launch rod!

I am looking to pick up a two stage model with a motor combination that will not fly out of sight.

[sandman]

Many years ago, when I started flying rockets, around 1970, I really liked two stage rockets. Back then you could get boosters in A, B, C and even shorties. The sight and sound of the staging was really cool. I had a rather large (for Estes) two stage rocket that would stage around 100 feet or more when the first stage was a C engine. When a B14-0 was used it really zipped off the pad and staged just past the launch rod!

I am looking to pick up a two stage model with a motor combination that will not fly out of sight.

About the closest you can come to the B14 today is the 24mm C11-0. If you can find them. There are a few left out there.

The TARC teams loved those motors but Estes stopped making them. maybe the new guys will bring the C11-0 back.

[gpoehlein]

About the closest you can come to the B14 today is the 24mm C11-0. If you can find them. There are a few left out there.

The TARC teams loved those motors but Estes stopped making them. maybe the new guys will bring the C11-0 back.

Estes has said in another thread that they will be bringing back the A10-0T, A8-0 and all the C11s (including the C11-0 and C11-7). These are supposed to be out early 2011 now.

Greg

[STRMan]

A thought occurs to me... What about a 24mm B11? There would be no need to drill the core to get the higher impulse like you get in a C11, just have half the propellant to keep the staging low where you can see it? It definitely seems doable, but I wonder if there is a market for such a beast. I know I would buy quite a few. Just thinking out loud here.

[Shreadvector]

A thought occurs to me... What about a 24mm B11? There would be no need to drill the core to get the higher impulse like you get in a C11, just have half the propellant to keep the staging low where you can see it? It definitely seems doable, but I wonder if there is a market for such a beast. I know I would buy quite a few. Just thinking out loud here.

A B version of the C11 would have a higher average thrust, possibly "12", but most likely not "14".

http://www.nar.org/SandT/pdf/Estes/C11.pdf


Of course, without the sustaining portion of the propellant in the casing, it may be hard to keep the pressure in from the peak with a booster. With a motor with a delay and ejection charge, the delay may keep in the pressure.

Here's an advertising suggestion: "WORLD'S MOST EXPENSIVE B MOTOR".

[sandman]

A B version of the C11 would have a higher average thrust, possibly "12", but most likely not "14".

http://www.nar.org/SandT/pdf/Estes/C11.pdf


Of course, without the sustaining portion of the propellant in the casing, it may be hard to keep the pressure in from the peak with a booster. With a motor with a delay and ejection charge, the delay may keep in the pressure.

Here's an advertising suggestion: "WORLD'S MOST EXPENSIVE B MOTOR".

Sounds close enough for me. :rolleyes:

Maybe I won't leave quite as many balsa fin parts behind on the deflector plate.

[jdbectec]

Sounds close enough for me. :rolleyes:

Maybe I won't leave quite as many balsa fin parts behind on the deflector plate.


The B8-0 would be close enough for me, and could be made if it indeed used a pintel for the core.

C5-0 and C5-3 would be nice to see again too.

I'd pay a premium price for all 3, as long as it wasn't a riduculous premium.

[ghrocketman]

If I can't get the beloved B14 back (and NO I have not seen ANY legitimate arguement why they can't be safely produced with AUTOMATED equipment), I would much rather have a 18mm B8-0 (and the C5-0,3 back too) than any sort of heavy-for-impulse 24mm B12 or 13 whatever.
I have NO interest in a 24mm B motor that they would be trying to charge double for 15 cents worth of x-tra cardboard.
I however would NOT have any problem paying a say 10-15% premium (but NOT some ignorant 30%+ premium) over common street B & Cprices to get something in the range of a B14, B8, or C5 back. I would probably buy more B8, B14, and C5 motors than any other type. I'd REALLY like to see a C5-5 if they could jam it in the case to the brim.

[Doug Sams]

I'd REALLY like to see a C5-5 if they could jam it in the case to the brim.Ya know...the "standard size" paradigm is very limiting as regards creativity and innovation. I don't know why they are stuck on 70mm long cases (for 18mm motors), or on paper cases for that matter.

AVI used longer cases. (Yes, they had burn thru issues, but we're talking about adding 2 secs of delay to a C, not stuffing a long burn D into it.) Why not have an 80mm series? Another good example is the Apogee micro motors. They had different length cases for the B, A and ½A motors. (Can't recall if the ¼A's were different or not...)

And why be limited to paper? As I understand it, going to a higher tech case is the key to making reliable, high thrust E and F impulse BP motors.

Give me a few days in the production area, and I'd have all sorts of exotic motors to play with :)

Seriously, I understand there has to be a critical mass before committing to a new motor type. You need minimal production runs to justify setting up the line. But one type of innovation is figuring out how to reduce the critical mass requirements that enable a new product rather than merely developing the new product.

It shouldn't be that hard to come up with a C5-5 (or C5-7). Maybe short fill them: ¾C's .

Doug

.

[jetlag]

The 70mm motor hooks used by just about everyone limits the motor choices to 70mm. It's that simple, at least to me. No reason to go to a longer case when so few modelers would be able to use this case easily in their current models. These motors would become 'orphan motors,' much like the rarely used (but necessary) orphan drugs out there with limited availability but absolutely needed drug therapy applications. Perhaps a better term used before is 'boutique motors.' Maybe this was a contributing factor to AVI's motors not 'taking off' saleswise.
Costs associated with these would be higher necessarily.
I'm afraid too many choices might turn off a new rocketeer with limited funds.
While one can wax nostalgically about these lost motors, I think they are gone for good.
Allen

[Doug Sams]

I'm afraid too many choices might turn off a new rocketeer with limited funds. I think that's the key. Anything other than 70mm can present major stumbling blocks to noobs and novices, which comprise much of the market. But, addressing the die hards, such as us YORF denizens, these variations shouldn't be too problematic. Yes, there will be some challenges in retro-fitting, but not deal breakers, I would think.

The 70mm motor hooks used by just about everyone limits the motor choices to 70mm. That's where we need a paradigm shift. I've gone to using hooks with no forward tang (& no forward motor block) in most of my builds. Three wraps of ¼" masking tape makes a perfectly reliable aft thrust ring and lets me use any length motors.

Maybe I'm being too optimistic, but, IMO, we need to think outside of this box more often.

Furthermore, I've seen cases where folks flew a rocket with the extra long motor hanging out the back :) Most kits are over stable enough to handle this. I've done it once or twice myself ;)

Doug

.

[jetlag]

Furthermore, I've seen cases where folks flew a rocket with the extra long motor hanging out the back :) Most kits are over stable enough to handle this. I've done it once or twice myself ;)

Doug.

Yes, I've stuck the E's in the shorter D motor mount with no problems. Awfully ugly, though!
But that's exactly what a kid would do when faced with, "I'm out of D's...wonder what would happen if I did THIS?"
Haven't we all been there!! :rolleyes:
But, that's part of the fun, eh?
Allen

[Shreadvector]

Yes, I've stuck the E's in the shorter D motor mount with no problems. Awfully ugly, though!
But that's exactly what a kid would do when faced with, "I'm out of D's...wonder what would happen if I did THIS?"
Haven't we all been there!! :rolleyes:
But, that's part of the fun, eh?
Allen

Unstable rockets? "It's all fun and games until someone loses an eye."

[Doug Sams]

A B version of the C11 would have a higher average thrust, possibly "12", but most likely not "14".

http://www.nar.org/SandT/pdf/Estes/C11.pdf
I ran the numbers using the cited NAR doc. Integrating the curve, the average thrust would be in the range 12.1 to 12.2N (depending on just exactly where the cutoff is). The total impulse would be between 4.4 and 5Ns, with 4.4 being right at half the total impulse of the existing C11.

This assumes, as stated, that the propellant doesn't burst thru before reaching this level...

I agree that it would be an impractically expensive B motor.

(I was compelled to get my geek jollies with this exercise :D)

Doug

.

[LeeR]

The 70mm motor hooks used by just about everyone limits the motor choices to 70mm. It's that simple, at least to me. No reason to go to a longer case when so few modelers would be able to use this case easily in their current models.

I think offering longer 18mm motors could be done similarly to the way Estes E motors coexist with D motors in the market. Longer hooks are made a standard part of many of the newer kits, and a spacer is included. And make them 1" longer, like the Estes E9s (95mm length), and you can use the same hooks already being produced. (And the Aerotech 24/60 reload hardware can be used, as well.)

[ghrocketman]

I'd like to see some REAL variety in longer motors as well. The E9 is darned near worthless to me unless used in clusters or as an upperstage motor. Having ONE flavor of motor (E9) in my book hardly justifies a longer case. Now something like a port burning D25 or E30 in that same case would be GREAT. Short of that, I'd much rather have the B14 or B8 and C5 lines back than any 60mm E9.
Also, I don't see the $22 something retail price of the 27 n-sec E9 as anywhere near realistic either when I can get a 3 pack of REAL 40 n-sec SU E15/E30 engines through valuerockets.com or a 3-pak of E18/E28 reloads for less as well.

[Doug Sams]

I'd like to see some REAL variety in longer motors as well. The E9 is darned near worthless to me unless used in clusters or as an upperstage motor. It's not high thrust (which I would definitely prefer), but it's not bad. In BT-60-ish rockets, it's great, and can go in bigger ones, if build light. It rocks in a Big Bertha or Big Betty.

As you noted, it's great as a sustainer. I have a two stage Big Betty that rocks on a D12-0 to E9-8 combo :)

Doug

.

[rstaff3]

While I'd be all for more options in the E9 form factor, I for one really like the E9's. I have plenty of rockets that fly great on them, including saucers, hats, monocopters, etc. And, yes, they are good in clusters too.

Any one who pays $22for a pack is paying way too much!

[PaulK]

...I for one really like the E9's. ...+1 on the E9. It fills a nice niche, and used properly, has quite a number of applications. If I want more thrust, I'll use an AT E18 reload. Now, back to the B14...

[ghrocketman]

It does not even HAVE to be the B14 exactly, but I do want TRUE port-burning SU BP 18mm and 24mm engines priced BELOW the cost of composite 18mm SU D21's through the valuerockets.com website.
D21's are GREAT, but are a bit much for some rockets.
Short of a REAL port-burner like the B14, the return of the B8 and C5 full lines (B8-0,3,5,7 and C5-0,3) would be acceptable as they at least can lift a DECENT amount of weight for their impulse level.
I'd really like to see the equivalent of the 18mm 13n-sec Cox D8-3 and D8-0 brought back too. The D8-3 was just about the PERFECT motor for the Estes/Semroc Mars Lander and 1284 full-stack Space Shuttle.

[Shreadvector]

The ValueRockets D10 motors do everything a B14 or a C5 could do, except act as an upper stage. But who NEEDS an upper stage with 20 N-s packed into a tiny lightweight 18x70mm package?

http://www.nar.org/SandT/pdf/Aerotech/D10.pdf

[GregGleason]

Does anyone have the .eng data on the B14?

Greg

[Doug Sams]

Does anyone have the .eng data on the B14?Greg,

I don't have time right at the moment to create one, but here's a graph I created using the NAR cert docs and the old Estes catalog curve (for the B14). The B14 curve is pretty simple. I think, if you pick 8 or 9 points, you'll get a very close representation. As few as six will probably work.

The 67 catalog lists this additional info (for the eng file):

Initial weight:
B14-0 0.61 oz
B14-5 0.69
B14-6 0.71
B14-7 0.73

Propellant weight:
B14-0 0.01566 pounds
B14-5 0.01374
B14-6 0.01374
B14-7 0.01374

(Notice this gives credence to the notion that extra powder is added for the -0 types to delay burn-thru/burst-thru until the sufficient impulse has been generated.)

You'll find Rocksim approximates all delays (of a basic type - eg, B14) as having the same propellant mass and initial weight. So you'll have to create a separate motor entry in the eng file for each different delay type if you want to fully use all the details. A good compromise may be just two entries - one for -5, -6 and -7, and another for the -0.

HTH.

Doug

.

[Bill]

The ValueRockets D10 motors do everything a B14 or a C5 could do, except act as an upper stage.



So how do you manage to use it as a booster for a BP sustainer?


Bill

[Doug Sams]

So how do you manage to use it as a booster for a BP sustainer?I have a couple projects in the queue where I plan to use a composite SU motor sans ejection charge as a booster. It will coast while the booster delay burns, then (hopefully) light the sustainer on burn-thru. So it will need to have gained enough speed to keep it pointing up, but that shouldn't be too hard to manage. I was gonna try a RoadRunner E25 gap-staged to a D12 or E9.

Doug

.

[ghrocketman]

I would use a small piece of green "cannon" fuse inserted into the BP engine sustainer nozzle down into the composite ejection well to ensure ignition of the sustainer.

[Doug Sams]

I would use a small piece of green "cannon" fuse inserted into the BP engine sustainer nozzle down into the composite ejection well to ensure ignition of the sustainer.That's a good idea. I'll hit up a couple DARS members to see if they have some. There are a couple Dr Frankenstein types I fly with who have a little bit of everything in their houses. Besides all sorts of pyro stuff, one guy has an enigma machine :)

Doug

.

[ghrocketman]

I have staged an Aerotech RMS24 E28T to an Estes C11-5 using the "fuse" method I described above more than once and it worked flawlessly. Delay elements of composites don't "spray" burning pieces of BP forward into the upper stage nozzle reliably like BP boosters, hence without the fuse I think staging would be very unreliable. I think you would probably have about a 80%+ lawn dart rate.

[Doug Sams]

Delay elements of composites don't "spray" burning pieces of BP forward into the upper stage nozzle reliably like BP boosters...Actually, we were thinking they would...if we left a little BP in the well :)

But trying the fuse idea sounds like a much better starting point ;)

Doug

.

[Gus]

Doug,

If you're trying to light an Estes 24mm motor you don't need a fuse. The nozzle of the 24mm motors is large enough that any burning particles coming up the gap-stage tube will hit propellant without a problem. But you do need a bit of loose black powder on top of the delay element of your booster motor. Burn through of the delay element on a composite motor won't be enough.

You don't need anywhere near a regular ejection charge amount, but you do need a small amount of powder. You'll be shocked at how much flame shoots up the tube from just a very tiny amount of black powder. The key is to run a few experiments to see how much powder you need. It's a trade-off between enough powder to carry the flame through the gap tube but not so much as to overpressurize the tube and blow the sustainer off before it lights (the upper end of your gap tube will need some vents).

The photo below shows three frames of a movie I did of a recent test trying to determine how much powder to use in a 1/8" diameter X one foot long gap tube. At the left end of the tube is an Estes igniter held in place in the tube by a tiny ball of Kleenex. I held the tube vertically and sprinkled a very tiny amount of black powder down on top of the Kleenex. (For reference I obtained the black powder by peeling apart an Estes C6-7 and salvaging the loose black powder ejection charge. Very similar stuff to what comes in Aerotech motors for use as the ejection charge. The amount of powder in the tube in the photo is probably 1/5th of what was in the C6-7)

The 3 frames are consecutive and were shot at 30 frames per second.

The first frame shows immediately before the igniter lights.

Second frame shows the small white spot at the left of the tube as the igniter lights.

Third frame shows the volume of flame at the other end of the tube 1/30th of a second later.

For a tube this small, it effectively works like fireworks "quick match", virtually instantaneous.

For a 24mm tube it will work almost the same if the volume of black powder is correct. I've been routinely gap staging Estes 13mm motors this summer (much smaller nozzles than the 24mm monsters). An A10-0 needs no additional black powder to gap stage more than a foot.

I've now moved on to gap staging 10.5mm motors (the purpose of the test in the photo). European Delta booster motors only put out a small spurt of flame (through a tiny port on their forward end) so if gap staged they need to be augmented with a little black powder. Deltas are particularly challenging because the sustainer nozzles are only ~1mm wide making for a very small target. Very difficult but particularly satisfying when you get it to work reliably. Members of the US Spacemodeling team need to be able to do this to compete in FAI altitude events.

Probably more info than you needed but I've spent some time on this recently and thought it might help.

Steve

[Doug Sams]

Snip great post!Great post, Steve. Thanks.

You pretty much confirm my scenario - a few grains of ejection BP on top of the delay grain.

I anticipate only a nominal gap, so I doubt I'll need a tube. I expected to have the E25's ejection hole lined up with the BP motor's nozzle, with only a ½" or so of gap. So I should be good to go, right?

Doug

.

[Doug Sams]

Deltas are particularly challenging because the sustainer nozzles are only ~1mm wide making for a very small target. Very difficult but particularly satisfying when you get it to work reliably. I want to know more about this <champing at bit>. I still have several Apogee BP boosters and long burn sustainers that I've never gotten around to staging. Would love to try some of your techniques to improve the reportedly difficult staging odds on these.

I still have a couple of birds in the unfinished pile (now on 10 years :)) that I could go back an finally finish to try this.

Doug

.

[JRThro]

Besides all sorts of pyro stuff, one guy has an enigma machine.
Does it have a riddle wrapped in a mystery inside it?

[Gus]

Great post, Steve. Thanks.

You pretty much confirm my scenario - a few grains of ejection BP on top of the delay grain.

I anticipate only a nominal gap, so I doubt I'll need a tube. I expected to have the E25's ejection hole lined up with the BP motor's nozzle, with only a ½" or so of gap. So I should be good to go, right?

Doug

.

I would think so, Doug, but my experiments this summer have shown that I'm occasionally wrong. ;) Again, overpressurizing the tube has been the biggest culprit in non-staging, sustainer pops off before lighting. Truly surprising how little powder is needed.


I want to know more about this <champing at bit>. I still have several Apogee BP boosters and long burn sustainers that I've never gotten around to staging. Would love to try some of your techniques to improve the reportedly difficult staging odds on these.

I still have a couple of birds in the unfinished pile (now on 10 years :)) that I could go back an finally finish to try this.

Doug

.

I did a bit of sustainer testing with old Apogee 10.5mm motors. Great, really fun motors. But, unfortunately, I wasn't able to find any boosters (so guard yours zealously). I'm in the home stretch of getting ready for Serbia but maybe when I get back at the end of August I'll do a thread on these types of altitude rockets.

For those who aren't aware, booster is 40mm diameter (Big Bertha size) about a foot long, topped with a 7 inch long 18mm sustainer. Adults are flying B impulse, Juniors A total impulse. Booster and sustainer must each have the same total impulse. Motors will be European 10.5mm motors (actually more like 10.1mm), piston launched. Booster and sustainer must each have their own recovery systems (no tumble recovery boosters allowed, so deploying a recovery system on the booster is a real trick). Sustainers will be carrying altimeters this year, for the first time.

Incredibly challenging, lots of fun.

Steve

[Doug Sams]

Again, overpressurizing the tube has been the biggest culprit in non-staging, sustainer pops off before lighting. Won't staging vents take of that? I use those on all my gap stagers.

In addition to that, I also apply a bit of tape to the staging coupler to give it a tiny bit of friction fit into the sustainer, to keep it attached a hair longer at staging. Buzz McD taught me that :)

You can see the piece of tape on the coupler below. (One of the vents is visible, too.)
http://www.doug79.com/midget-K-40/midget-booster-k-40-6p.jpg

Doug

.

[blackshire]

I want to know more about this <champing at bit>. I still have several Apogee BP boosters and long burn sustainers that I've never gotten around to staging. Would love to try some of your techniques to improve the reportedly difficult staging odds on these.

I still have a couple of birds in the unfinished pile (now on 10 years :)) that I could go back an finally finish to try this.

Doug

.If memory serves, the two-stage version of the 10.5 mm Micro Motor-powered Apogee Components Centrix (see: www.rocketreviews.com/cgi-bin/search/searchall.cgi?Centrix ) used a special "Staging Igniter," which was simply a fuse (thinner than green "cannon fuse," I believe) that was inserted into the upper stage motor's nozzle and was lit by the burn-through of the booster motor's propellant grain.

[Doug Sams]

If memory serves, the two-stage version of the 10.5 mm Micro Motor-powered Apogee Components Centrix (see: www.rocketreviews.com/cgi-bin/search/searchall.cgi?Centrix (http://www.rocketreviews.com/cgi-bin/search/searchall.cgi?Centrix) ) used a special "Staging Igniter," which was simply a fuse (thinner than green "cannon fuse," I believe) that was inserted into the upper stage motor's nozzle and was lit by the burn-through of the booster motor's propellant grain.It was a thin piece of wire dipped in pyrogen. I have some stashed with my Apogee motors. My take - not to discredit Tim/Apogee - was that the wire was as likely to block the nozzle and prevent ignition as it was to enhance it :) That's an inexperienced assessment, so it's not fair to conclude anything negative about Apogee. It's just my conservative engineering take.

And that's why, if Steve has some good tricks learned from the Delta motors, I'm all ears :) That is, if there's something to make me more confident about staging these things successfully, I'm anxious to learn it.

As an aside, one of the ideas I had was to mix the Apogee motors with others. For example, instead of staging an Apogee A2-0 to an A2-5 or A2-7, I thought I'd stage it to an Estes motor, such as an A3-4T, where I have lots more experience. Similarly, I considered using an Estes booster with the Apogee sustainer, thinking I might be able to use this combo in such as way as enhance the ignition odds. Just some ideas...

Doug

.

[Gus]

And that's why, if Steve has some good tricks learned from the Delta motors, I'm all ears :) That is, if there's something to make me more confident about staging these things successfully, I'm anxious to learn it.

Doug

.
Doug,

Some of the past FAI altitude folks used a tiny piece of thermalite (no longer legal to own) in the sustainer motor nozzle held in place by a little mound of black powder covered with tissue and stuck in place with ambroid cement. WAY too complicated for me, and one prior contestant told me he never got it to work reliably.

I tried using a piece of visco fuse, fit fine, but I had to be sure to fray the end of the fuse to enlarge the target area for the flying burning bits. As you suspected, the fuse filled the nozzle preventing any direct ignition and the frayed fuse end wasn't really any bigger than the nozzle so I didn't see the advantage. I got it to work a couple of times but adding the fuse also presented the problem of how to keep it in place during boost creating another failure mode.

With the tiny Deltas the key is to have a "flash tube" which runs from the booster directly to the sustainer nozzle. Some folks are making these out of fiberglass but I just used Totally Tubular T2 tubing which is roughly 3/16" launch lug size. The tube is narrow enough to fit inside the forward end of the booster motor and actually sits up against the top of the propellant. That tube runs all the way up to the nozzle of the sustainer. The "flash tube" has holes in its forward end for venting.

The flash tube runs between pieces of 10.5 mm tubing which serve as the motor mount for the booster at the bottom and the seat for the sustainer motor at the top.

Hope that helps.

Steve

[Jerry Irvine]

I have used Apogee BP motors and micro-composites. Those motors are worth twice the price. Upper staging and basic ignition of small nozzle motors can be done with Jetex or Thermalite fuse. While those are hard to come by commercially these days, an old Centuri Sure-Shot is the same thing. I have seen instructions on the internet on how to make Thermalite wick/fuse clone from scratch. CXA Canada used to make it.

Ultra tiny through nozzle igniters for SU composites are the main limiting factor of technology. For that you need a 32-44 gage nichrome wire which is coated with enamel or paint to prevent shorting during ignition. Trying to coat it with pyrogen is difficult for a variety of reasons.

One thing that can work is to use a syringe and put a single drop of dupro cement through the core and toward the delay/bulkhead then immediately put powdered black powder or pyrodex through the nozzle so it sticks to the glue. Then a bare nichrome wire will work most of the time.

Tiny APCP SU motors should have a tiny Pyrodex pellet installed in the core during manufacture.

On the "legal to own" fear mongering, if an igniter was ever recommended for use with model rocket motors they are ATF exempt under 27 CFR 555.141-a-7. You don't even have to give them a cute new name like "initiator". :)

Jerry

[blackshire]

With the tiny Deltas the key is to have a "flash tube" which runs from the booster directly to the sustainer nozzle. Some folks are making these out of fiberglass but I just used Totally Tubular T2 tubing which is roughly 3/16" launch lug size. The tube is narrow enough to fit inside the forward end of the booster motor and actually sits up against the top of the propellant. That tube runs all the way up to the nozzle of the sustainer. The "flash tube" has holes in its forward end for venting.A Russian two-stage FAI model whose plans I saw in Taras Tataryn's Advanced Rocketry Group Ltd. publication (he's in Mississauga, Ontario in Canada) several years ago had a black powder "flash tube" in the shape of a very long, thin funnel made of very thin-walled fiberglass. The mouth of the "funnel" fit into the upper end of the booster motor, and the slender neck extended several inches (almost a foot, if memory serves) up through the booster's airframe to the upper stage motor's nozzle. I believe the booster had a rear-ejection motor mount and used a streamer for recovery.

[Gus]

Blackshire,

The rear ejection booster motor mount was ejected by a separate black powder charge which was lit by a fuse which was ignited by the motor's ejection charge. The reason for the fuse leading to the second black powder charge was to give the sustainer time to pull away before the booster streamer deployed.

Did I mention that these FAI altitude models are a bit complicated? :)

[blackshire]

Blackshire,

The rear ejection booster motor mount was ejected by a separate black powder charge which was lit by a fuse which was ignited by the motor's ejection charge. The reason for the fuse leading to the second black powder charge was to give the sustainer time to pull away before the booster streamer deployed.

Did I mention that these FAI altitude models are a bit complicated? :)For a two-stage scale model that requires gap-staging (such as a Sandia "Doorknob" nuclear mushroom cloud-sampling sounding rocket), I'd rather use Evan "Buzz" Nau's gap-staged booster recovery methods because they don't require fuses, "flash tubes," or other special items. The simpler of his two methods combines G. Harry Stine's vented gap-staging system for long boosters with a rear-ejection booster motor mount (tied to the booster airframe tube via a shock cord) that has a streamer packed between the booster motor mount tube and the booster body tube.

[ghrocketman]

Agree that Gus's method of BP in the ejection well will work also; I have found the fuse method to be easier without any need to worry about overpressurization as with the BP.
If one is worried about the fuse falling out of the sustainer, glue it into the nozzle with a small amount of Ambroid or Sig-ment airplane or other FLAMMABLE cement. the fuse directly contacting the upper stage grain INCREASES reliability. one can increase it further by putting a VERY small amount of BP in the ejection well ALONG with using the fuse. The BP will cause the fuse to be almost completely consumed immediately.

[Initiator001]

At NARAM-52 this afternoon, I flew a Canaroc B14-7 in an Estes RTF Athena model under the provisions of the NAR Expired Motor Flight Test Program. I used a Quest Q2G2 ignitor.

I was very impressed. If you blinked, you missed it. :eek:

I recovered the rocket without any problems. :)

Bob

[LeeR]

Bob,

I heard about flash floods on weather reports -- hope all is fine in Pueblo. A friend and I are driving down in the morning.

[Initiator001]

Bob,

I heard about flash floods on weather reports -- hope all is fine in Pueblo. A friend and I are driving down in the morning.

It was raining pretty solid all Friday night.

Saturday was fine and dry.

No weather issues here. :)

Bob

[GregGleason]

At NARAM-52 this afternoon, I flew a Canaroc B14-7 in an Estes RTF Athena model under the provisions of the NAR Expired Motor Flight Test Program. I used a Quest Q2G2 ignitor.

I was very impressed. If you blinked, you missed it. :eek:

I recovered the rocket without any problems. :)

Bob

Wow! You know when you get a picture of a smoke trail it is a fast mover.

Greg

[Initiator001]

The subject of the B14 motor was brought up at the NARAM-52 Manuafcturer's Forum.

John Boren (aka JumpJet here on YORF), the Estes R&D Manager, stated that the B14 will not be coming back.

The main reason: Low sales volume does not justify production of the motor. :(

I understand, it's a business decision.

Bob

[Jerry Irvine]

The subject of the B14 motor was brought up at the NARAM-52 Manuafcturer's Forum.

John Boren (aka JumpJet here on YORF), the Estes R&D Manager, stated that the B14 will not be coming back.

The main reason: Low sales volume does not justify production of the motor. :(

I understand, it's a business decision.

Bob
So get 10 guys together with more money than brains and buy a run. It's only like $20k wholesale.

Jerry

[Bazookadale]

So get 10 guys together with more money than brains and buy a run. It's only like $20k wholesale.

Jerry

I don't have a lot of money but I have less brains, so are there 9 more like me out there?

[GregGleason]

The subject of the B14 motor was brought up at the NARAM-52 Manuafcturer's Forum.

John Boren (aka JumpJet here on YORF), the Estes R&D Manager, stated that the B14 will not be coming back.

The main reason: Low sales volume does not justify production of the motor. :(

I understand, it's a business decision.

Bob

Oh, well.

At least least we have an answer. And at we have AP motors. But if someone wants to go through the pain and hassle, it can be done. It appears not to be a technical issue, just an economic one.

Greg

[STRMan]

The main reason: Low sales volume does not justify production of the motor.

Hummmm... I just don't buy it.

Don't get me wrong - I am VERY VERY happy that we can look forward to the return of the A8-0, A10-0T, and the rest of the C-11 line, but can any of these engines be more popular than the B14 line? If they are looking simply at the sales rates when they last produced B-14's years ago, then I suspect they are making a decision on outdated info. Now that we as rocketeers have had to live life without these high impulse B engines, I don't think we will EVER take them for granted again.

Then again, these other engines still have similar siblings in production, so maybe running them is less cost prohibitive than starting up a whole B14 line again. If I was asked, I would GLADLY trade off either the entire B4 OR B6 line for the B14 line. I know B4's and B6's have different characteristics from each other, but any rocket that will fly on one will easily fly on the other. The B14 is an all together different animal that open up's different flight possibilities.

I hope they do a little more market research and revisit this decision someday down the road.

[raohara]

I don't have a lot of money but I have less brains, so are there 9 more like me out there?
I am skeptical they would do it. But if it is possible, count me as interested.

- Rich

[blackshire]

The subject of the B14 motor was brought up at the NARAM-52 Manuafcturer's Forum.

John Boren (aka JumpJet here on YORF), the Estes R&D Manager, stated that the B14 will not be coming back.

The main reason: Low sales volume does not justify production of the motor. :(

I understand, it's a business decision.

BobYou've created a radio serial cliff-hanger scene there, Bob! :-) What (if anything) did Mr. Boren say about the possibility of Estes bringing back the B8, C5, and C11 motors? Regarding the B14, I'm hoping that Quest President Bill Stine read your posting above and thought, "So Estes is abandoning that motor, eh? Hmmm..."

[ghrocketman]

I don't buy the fact that it would be a low production motor based on the fact of all those that are very active on the forums wanting the motors.
I think that is just another lame excuse to not produce a needed motor that is not simply ramming powder into a tube.
I for one would probably buy nothing other than varieties of the B14 for ALL my B motors for at least 3 years based on the stockpile I have of various B6 and B4 motors. Probably would do the same if they bring back the B8 as long as they offer it in -3,5,7, and -0 varieties.

I would actually rather hear a manufacturer just say "we don't wanna do it" rather than hear baloney excuses about low volume or safety or numerous other lines of bunk that can all be refuted.

If Estes does not want the B14 business, I would just as soon see another manufacturer come out with a motor such as this that NOBODY else offers which would fill a real need instead of either offering "me too" motors or low thrust motors that nobody I'm aware of is actually asking for.

[Initiator001]

You've created a radio serial cliff-hanger scene there, Bob! :-) What (if anything) did Mr. Boren say about the possibility of Estes bringing back the B8, C5, and C11 motors? Regarding the B14, I'm hoping that Quest President Bill Stine read your posting above and thought, "So Estes is abandoning that motor, eh? Hmmm..."

The C11 are awaiting their DOT and other approvals since they were out of production. I believe John Boren said to expect the C11s to be available in the Spring next year.

The A10-0T & A8-0 motors are planned to be available at the end of this year. :)

John was asked about the C5-3. I can't remember his exact answer. I THINK he said it was something that had not been discussed.

B8. No.

Bill Stine was asked about Quest making B14 motors. His reply was no.

Bob

[Jerry Irvine]

Did anyone at all mention a D40?

[blackshire]

The C11 are awaiting their DOT and other approvals since they were out of production. I believe John Boren said to expect the C11s to be available in the Spring next year.

The A10-0T & A8-0 motors are planned to be available at the end of this year. :)

John was asked about the C5-3. I can't remember his exact answer. I THINK he said it was something that had not been discussed.

B8. No.

Bill Stine was asked about Quest making B14 motors. His reply was no.

BobBob, I thank you for filling this in for us! Where there is a demand, supply will follow...from somewhere. One of the Eastern European FAI contest BP motor makers such as Delta (or perhaps Doctor Z's company) could "clean up" in this niche market, especially if they partnered with a U.S. or Canadian "angel investor" to get their B14 and B8 motors certified by the NAR and CAR.

[Jerry Irvine]

Bob, I thank you for filling this in for us! Where there is a demand, supply will follow...from somewhere. One of the Eastern European FAI contest BP motor makers such as Delta (or perhaps Doctor Z's company) could "clean up" in this niche market, especially if they partnered with a U.S. or Canadian "angel investor" to get their B14 and B8 motors certified by the NAR and CAR.
You would be shocked at the morass of regulation to overcome from CE to UN to DOT to (weapons import regs). It tripped up Quest for an extended time and he is an expert on the topic, at least as compared to most. I would suggest a company already versed in the process with a fondness for rocketry be used as the conduit for such a thing as the hard costs would be silly otherwise. $200 D's are not out of the question. One might start by being nice to such folks when they present themselves.

It would actually be cheaper and more practical to set up a small plant in the USA, but NOT in CA!

There have been rocket factory accidents with deaths in CA, NV, and AZ, so some other state would be good and I suggest not screwing with CO so some outlier does not take down Estes. We need them.

Jerry

[ghrocketman]

While I think it is great that Estes is bringing back the A8-0, A10-0T, C11-0,5,7 I question that ANY of these motors would sell as well as the B14-x, B8-x, or C5-x., especially the C11-7.
The C11-7 is worthless for anything but either the lightest 24mm rockets as a single-stage motor or as the upper stage for a lower flight on an Astron Omega.
The C5-3 could replace ALL uses for the C6-3; it has more kick off the pad along with a longer tapering off thrust duration. Rockets that use the C6-3 ALWAYS get up to speed faster AND ALWAYS fly higher on the C5-3; the C6-3 makes no sense side-by-side to the C5-3.
While both the A8-0 and A10-0T are good booster motors, we really only need one or the other. I'd prefer the A8-0, but that cannot be used in 13mm rockets like the A10-0T can be used in 18mm with an adaptor. How many 13mm two stage rockets are there really other than the Astron Beta anyway ?
The B14 especially in booster form would give us something we do not currently have- a BP motor with REAL kick. It will lift more than the D12. Short of that give me the B8; I'd rather see the B8 booster return rather than the C5 or C11 booster due to the fact it will lift as much as the C11, but you can still fly a two-stager to a lower altitude.
I for one would have no problem paying say $9/pak street price for B14 motors but will never do that for anything else 18mm; I ALWAYS buy my other motors at 40-50% off at Michaels/Hobby Lobby.

[Doug Sams]

How many 13mm two stage rockets are there really other than the Astron Beta anyway ?:D:D:D:D:D

Lots! At least in my collection, anyway. The Mini Brute Midget (Est 0840) was the other 2-stager alongside the Mini Brute Beta. I have an 0840 clone along with several other variations.

The A10-0T has plenty of oomph to get a 3-stage Midget going. And this variant uses three A10-0T's at a time:
http://www.doug79.com/thridget60/T60-onthepad-p.jpg


While both the A8-0 and A10-0T are good booster motors, we really only need one or the other. I'd prefer the A8-0, but that cannot be used in 13mm rockets like the A10-0T can be used in 18mm with an adaptor.If we can't have both, yours is the correct logic. With an adaptor, the A10-0T can pretty much do everything the A8-0 does. I'm sure there's some niche bird out there that suffers under the long tail of the A10-0T, but that case is marginal to start with.

A couple of other 2-stage T-motored birds were the Sting Ray and the Mini Cobra, although both of them will about fly out of sight before staging. They're really better suited for ½A boosters.

Doug

.

[LeeR]

How many 13mm two stage rockets are there really other than the Astron Beta anyway ?

I'm getting interested in the cardstock rockets and have downloaded a lot of the patterns. The A10-0T would be great for a bunch of BT5-sized two-stage rockets. I'll take either A booster! But given the choice, the A10-0T is the more versatile.

And if I see one more Midget picture from Doug, I'm going to give in to the cuteness factor for sure and build one ...:)

[blackshire]

-SNIP- How many 13mm two stage rockets are there really other than the Astron Beta anyway ? -SNIP-Semroc's Booster-16 (see: http://www.rocketreviews.com/reviews/all/sem_booster_16.shtml ), which fits rockets having ST-16 body tubes (such as the Centurion, Vega, and Goliath) uses A10-0T booster motors. Also, as Doug mentioned, the two-stage Sting Ray from the Mini Tri Pak combo kit (see: http://www.spacemodeling.org/jimz/est0866.htm ) and the two-stage Mini-Cobra (see: http://www.spacemodeling.org/jimz/est0898.htm ), along with the late-model Astron Midget (that's a purty 'un, Doug!) all need the A10-0T for their boosters. Another A10-0T use is for CHAD staging with other rockets, from ST-5/BT-5 diameter on up.

[jflis]

How many 13mm two stage rockets are there really other than the Astron Beta anyway ?


We (FlisKits) have several ideas that never got into production because there weren't any motor's (or not enough of a selection). It's a classic chicken/egg situation... :)

[Bob H]

I'm getting interested in the cardstock rockets and have downloaded a lot of the patterns. The A10-0T would be great for a bunch of BT5-sized two-stage rockets. like this one?

[LeeR]

That's what I'm talkin' about!

[Doug Sams]

The A10-0T would be great for a bunch of BT5-sized two-stage rockets. Don't be fooled, Lee. It's a 2.2Ns A, nearly full. In a BT-5, that's a minimum diameter bird ala Mosquitos and Quarks, and we know those teleport on anything over a ¼A :) BT-20 and BT-50 birds are better matches for the A10-0T. BT-5 rockets like the aforementioned Mini Cobra and Sting Ray are very nearly over powered on it.

I've flown my Sting Ray once (maybe twice) and used a scarce ½A3-0T staged to a ¼A3-3T to keep it recoverable :)

Doug

.

[Doug Sams]

And if I see one more Midget picture from Doug, I'm going to give in to the cuteness factor for sure and build one ...:)
http://www.doug79.com/stridget/tridget5-3.jpg
Here's your A10-0T eater. Bring lots of eyes, put a ½A3-4T in the sustainer, and don't look away :)

Doug

.

[Jerry Irvine]

http://www.doug79.com/stridget/tridget5-3.jpg
Here's your A10-0T eater. Bring lots of eyes, put a ½A3-4T in the sustainer
That's a pretty Midget-like rocket. Do the stages ever stabilize after sep?

That would be a good scale-up to 18mm for the B14-0 discussion or A8-0 to A8-0 to A8-5 in a small field. I used to have a similar rocket that would leave stages near the pad but then warp away with a higher power upper stage. Crowds loved it. I think it was B6-0, A8-0, C6-7.

Of course I wish new Estes would make 24mm D40-0,4,8 so that Tridget could do D40 to D40 to E9. I used to optically track a lot of rockets, but that would be a challenge. One worth experiencing.

Jerry

[ghrocketman]

I for one would MUCH rather have Estes bring back the 1/2A3-0T instead of the A10-0T as it would be much easier to track staging of the Beta and Stingray.
I used to like to have a warp-stage flight in my old Astron Delta and Astron Avenger using a combo of A8-0 to B14-5 or B14-7. It was a real crowd pleaser as they would both stage fairly low than warp off when the B14 lit. The Delta actually flew quite high, but I don't think the Avenger hit more than maybe 700' as it was only 7.5 n-sec of power.

That D40 sounds interesting; did Estes make protoypes of those some time back or what's the story there ?
I know that Estes listed an E30-5 and E30-7 as suitable motors for the Pro-Series Terrier/Sandhawk on the kit box but never produced those motors either. I'd actually like the background story of the Estes E30 as well if anyone knows it.

[Jerry Irvine]

That D40 sounds interesting; did Estes make protoypes of those some time back or what's the story there ?
I know that Estes listed an E30-5 and E30-7 as suitable motors for the Pro-Series Terrier/Sandhawk on the kit box but never produced those motors either. I'd actually like the background story of the Estes E30 as well if anyone knows it.
I don't follow all the details, but I have seen D40 prototypes flown. I am not sure if the E30 was one of the planned future NCR motors (29mm) or a planned 24mm cheater E. I have also seen D12 length high thrust D's which may actually be the D30. It would be limited to 0 and 3 second delays unless they pulled a D11 trick and make a crippled power longer delay.

The advantages to an E9 casing D40 are many. It could be as close to an actual full 20 N-s D as Estes can make. The D12 is 16.2 N-s last I checked. The E9 case D40 (or whatever) would be USPS mailable which is a major issue Barry Tunik had dealing with E9's and NCR F62's. It could have a limited number of SKU's such as D40-0, D40-4, D40-8 to work well in most Estes kits. The only variant I would consider from that would be D40-0,3,7,11 so the 3 would work better on the Saturn V. My preferred Saturn V flight would be D40-0 drop-staged to D12-3.

I wish for 1/2A3-0T and 1/4A3-4T as well. But they culled SKU's years ago due to the loss of the organized club networks associated with city recreation departments, who had institutionalized the process of attracting and training model rocketeers which involved as much variety as quantity.

These days it's all about what can be sold to a homogeneous mass-market audience. The D40 does that and the 1/2A3-0T does not.

Jerry

[ghrocketman]

Correct me if I'm wrong, but does not the USPS set their OWN limits as to what is mailable through their service separate from DOT regs ? I was under the impression that witin their service they are not subject to the DOT requirements that FedEx, UPS, brand X, etc private carriers are subject to.

The whole haz-mat shipping BS cash-grab regulations are a whole other can of worms not on point in this thread anyway; suffice it to say I think the vast majority of the shipping regs are a HUGE crock of steaming canine fecal matter that stinketh to high heaven anyway.

I for one see the A10-0T as a much HIGHER specialized motor than the B14, B8, and C5 lines, all of which would have more utility than the A10-0T. I see the 1/2A3-0T as having more value than the A10-0T to the vast majority of dedicated rocketry hobbyists. Why a manufacturer would choose to bring out essentially the same motor in 13mm and 18mm flavors (A10-0T and A8-0) does not make sense either as bringing out the A8-0 and 1/2A3-0T give one more choices, not the same choice in just a different package.

I guess I should not complain; at least people at the helm are listening somewhat to what we want and are bringing back at least 5 motors we have not had in years; I just wish they were ones of more value. I'd still take one new motor in the B14-0 than all five of the ones they are bringing back as I think it would have more purpose.

[LeeR]

Don't be fooled, Lee. It's a 2.2Ns A, nearly full. In a BT-5, that's a minimum diameter bird ala Mosquitos and Quarks, and we know those teleport on anything over a ¼A :) BT-20 and BT-50 birds are better matches for the A10-0T. BT-5 rockets like the aforementioned Mini Cobra and Sting Ray are very nearly over powered on it.

I've flown my Sting Ray once (maybe twice) and used a scarce ½A3-0T staged to a ¼A3-3T to keep it recoverable :)

Doug

.

OK, let me re-phrase ... "The A10-0T would be great for a bunch of two-stage rockets."

And I saw that Tridget posting -- enough already! And I always had a thing for BNC-50J nose cones, too ...

[blackshire]

OK, let me re-phrase ... "The A10-0T would be great for a bunch of two-stage rockets."

And I saw that Tridget posting -- enough already! And I always had a thing for BNC-50J nose cones, too ...

Rather like what is done in draft horse weight pulling contests, Thoroughbred horse racing, Quarter Horse racing, and Standardbred (trotter and pacer) harness horse racing, we could "handicap" our higher-performing two-stage mini motor models (such as the Sting Ray, Mini-Cobra, and Beta) so that they wouldn't fly out of sight on A10-0T powered boosters. A small lead "sinker" fishing line weight could be affixed to a plastic nose cone's molded eyelet (or to the screw eye of a balsa nose cone) using a snap swivel and a very short length of string. This "handicapping" weight could be quickly removed for flying the upper stages of such rockets as single-stage models.

[Bob H]

Don't be fooled, Lee. It's a 2.2Ns A, nearly full. In a BT-5, that's a minimum diameter bird ala Mosquitos and Quarks, and we know those teleport on anything over a ¼A :) BT-20 and BT-50 birds are better matches for the A10-0T. BT-5 rockets like the aforementioned Mini Cobra and Sting Ray are very nearly over powered on it.

I've flown my Sting Ray once (maybe twice) and used a scarce ½A3-0T staged to a ¼A3-3T to keep it recoverable :)

Doug

.I've got to agree with Doug here.

The Cardstock BT-5 Omega has been flown 3 times in almost no wind conditions.

Each time was on a 1/2A3-0T staged to a 1/2A3-4T and if it weren't for the fact that one of the other club members spotted the sustainer, I would have lost it on 2 of the 3 flights.

[STRMan]

OK, so if a B14 is SO much more dangerous to make because of the drilling of the core, and a B8 was made with a pintle, is there something that can be made in between them? A B10? B11? B12? What is the maximum impulse that can be realized with the pintle method?

[Jerry Irvine]

The motor machines were made by Vern. If there were simply a core drilling machine made as a second operation, it could be done in an automated, safe way.

The other possibility is to have the B14 fans themselves come to Penrose on B14 drilling days. :D

I have drilled hundreds of D12's to D22's and it is reliable and, based entirely on experience, safe.

Jerry (volunteer)

[Bill]

OK, so if a B14 is SO much more dangerous to make because of the drilling of the core, and a B8 was made with a pintle, is there something that can be made in between them? A B10? B11? B12? What is the maximum impulse that can be realized with the pintle method?


I would expect that the B8 is already the optimum tradeoff between safety and the efficiency and longevity of the maunfacturing tools vs peak thrust. I am a "design engineer", not a "manufacturing engineer". There is a big difference and I learned a bunch about it talking with Carl at NARAM.


Bill

[Jerry Irvine]

Because black powder is amorphous and because the existing machine was optimized for endburning grain geometries, and because of the small size, the making of longer cores can result in areas of less complete packing or even voids in rare cases.

The FSI F100 (1.04 x 6", 42E48) was a large coreburner, but because the diameter was more than double and the tooling was optimized for "concentric packing" and notably because they were made by hand which gives a feedback loop a machine lacks, they were practical.

The B14 needs to be drilled unless an entirely new packing jig is designed and tested.

There needs to be a semi-automatic machine for core drilling on the B14 and D40 (0.93 x 3.75").

If a 0.69 x 3.75" D5 is added, then a C18 will also become practical.

Jerry

[Bazookadale]

I am a "design engineer", not a "manufacturing engineer". There is a big difference and I learned a bunch about it talking with Carl at NARAM.


Bill

One thing I learned early in my career is never get in the middle of a design engineer,a manufacturing engineer, a production engineer and a safety engineer having an argument - you will be drawn and quartered :chuckle:

[ghrocketman]

If the B14 could be made relatively safely back in 1970, it CERTAINLY can be made NOW in a MORE safe manner. The current "low sales volume" arguement currently touted by the "new" Estes holds ZERO water as we all know here on the forum we would ALL be buying them by the case load.

[Joe Wooten]

One thing I learned early in my career is never get in the middle of a design engineer,a manufacturing engineer, a production engineer and a safety engineer having an argument - you will be drawn and quartered :chuckle:

The test engineer trumps them all....... :chuckle:

[Doug Sams]

The test engineer trumps them all....... :chuckle:I spent a year in test engineering. It wasn't for me, and I didn't appreciate it at the time. (In hindsight, if I'd been working for a different group, it might have been an entirely different experience and left me with a totally different perspective.) But over the years, working with customers as well as doing design and debug of circuits, I've learned one unassailable axiom: One test is worth a thousand expert opinions :D

Doug

.

[Joe Wooten]

I spent a year in test engineering. It wasn't for me, and I didn't appreciate it at the time. (In hindsight, if I'd been working for a different group, it might have been an entirely different experience and left me with a totally different perspective.) But over the years, working with customers as well as doing design and debug of circuits, I've learned one unassailable axiom: One test is worth a thousand expert opinions :D

Doug

.

I spent almost 25 years doing testing at nuclear plants. A good test engineer also has to be good at design, because you have to suggest design changes (or write them). Now I'm doing mostly design work for the new nukes we are building. Field testing is for the younger guys with good knees...... :D

[JStarStar]

Mulling over the whole issue last night, one question occurred to me: could the B14 issue be related in an indirect manner with the disappearance of the late lamented E15 of a decade ago?

I suppose there are probably structural limitations as to the average thrust the paper casing/ceramic-clay nozzle combination will consistently and safely withstand without blowout. As we know the E15 had persistent CATO problems so it would be a reasonable guess (not being a professional pyrotechnician I might just be shooting in the dark) that there may be a limit between 12-15 Nt as the maximum average thrust the casings/nozzles can handle.

Although the fact B14s (and before that, B3s) were used for about 15 years without unusually high CATO rates (at least as far as I ever heard) would argue against that theory.

Plus, I don't think there have been any suggestions by anybody from Estes that the decision to drop/not bring back the B14s had anything to do with performance problems with the motor itself.

[Shreadvector]

No.


Cato is not "CATO".

No to the B14 and E15 being in any way related. One was 18mm and the other 24mm and the B14 was manually drilled to form the deep part of the core. The E15 was not drilled at all and had a very shallow core. it also had a very tiny nozzle and the internal pressure was just too high - plus there was ALLEGEDLY some kind of problem with the big grain aging and drying out and cracking. No such problem on a B14. There was a problem with year "X" C5-3 motors. Others were fine.


Mulling over the whole issue last night, one question occurred to me: could the B14 issue be related in an indirect manner with the disappearance of the late lamented E15 of a decade ago?

I suppose there are probably structural limitations as to the average thrust the paper casing/ceramic-clay nozzle combination will consistently and safely withstand without blowout. As we know the E15 had persistent CATO problems so it would be a reasonable guess (not being a professional pyrotechnician I might just be shooting in the dark) that there may be a limit between 12-15 Nt as the maximum average thrust the casings/nozzles can handle.

Although the fact B14s (and before that, B3s) were used for about 15 years without unusually high CATO rates (at least as far as I ever heard) would argue against that theory.

[JStarStar]

CATO =

Catastrophe
At
Take
Off

That's how I use it. Correct me if you feel compelled but you'll be wasting your time. ;)

[Shreadvector]

CATO =

Catastrophe
At
Take
Off

That's how I use it. Correct me if you feel compelled but you'll be wasting your time. ;)

I already corrected it without wasting my time. The document that points out how why this is a false-acronym is in my signature. You may continue to think the Earth is flat and that rockets "take off" or that a motor failure at or near the end of propellant burn or a missing ejection charge is at "take off", but I will not be forced to be "dumbed-down" or to stop speaking the truth.

[jetlag]

Gosh, Fred,
A little OCD on the CATO definition, eh?
Let it go, man! Like the word 'hopefully' or further/farther, etc. I've read your treatise on CATO, BTW.
Blood pressure is a precious thing to waste.
Allen

[ghrocketman]

Fred just likes to nit-pick things to death whether we give a plague-infested rat's behind or not.
The blathering diatribe about CATO vs. cato vs. Cato or his standard "did you call the manufacturer" quip is neither wanted nor appreciated by the majority (probably 99%) of us on this forum as it is primarily useless.
Almost as irritating as my EX-wifes worthless incessant nagging/nit picking when I was married. After a while it is very easy to ignore and just permanently TUNE OUT.
Most would resign themselves to knowing they are correct WITHOUT continuing to irritate / piss off those WHO DON'T FREAKIN' CARE AND DON'T WANNA HEAR IT !!!!

[Shreadvector]

Yes indeed. Why call a manufacturer to ask them a question about their products when you can simply post it here and get false-insane-ravings?


how about those folks raving about Estes and calling for a boycott? Did you read my posts in the thread here and TRF? Was I calm and rational and correct? And how about you folks? How did you all do?

And again, I post facts about the term cato and you want to try to bully me into accepting a B.S. made-up and clearly incorrect meaning. i laugh at you all as you proclaim with great pride how you love to be ignorant and want to spread it to everyone else.

Just like the hate filled posts of our favorite forum polluter who can't wait for a new opportuinity to attack either a manufacturer, another poster, his e-wife (why did you marry her if you hate her so much?), the government, safety codes, or any rational behavior that includes respecting the rights and property of others (giving people motors that have been hit with a hammer to intentionally destroy their rocket which they spent time and money on, laughing and rejoicing when a rocket is accidentally destroyed, etc.).

Seems like a psycopathic and sadistic personality. At least that's my opinion based upon the public postings. in addition to destroying other's rockets, do you also enjoy killing their pets (using your gun, car, etc.)?

[ghrocketman]

Fred,

1) I never said I hate anyone or anything (other than 95% of all left-wing enviro-whacko nut-job favor-every-freak-of-the-week KOOK things California)

2) Never harmed any pets and value and treat my own dog better than MOST people's children are. She eats better too. :p

3) Most on these forums are intelligent enough to contact manufacturers if they choose to do so; most look to forums for information WITHOUT having to do that and to see if any "inside" info is available.

4) Your condecending/arrogant/pompous sounding posts (whether you intend them to sound that way or not, at a minimum they sound smart-assed) are neither appreciated nor wanted by most on the forum. I am just one of few bold enough to say so. Might make for a good poll.

5)The motor whack with a hammer gag was done way back during when I was in junior high/high school freshman days. I would neither do it now nor reccommend anyone else do it now. I do stand by the statement that it was hilarious back then though ! Notice that one of my buddies got me with the same gag and destroyed a pristine Mars Lander back then...what goes around comes around and we deserved it.

6)Totally respect the rights of property owners to do with THEIR property AS THEY SEE FIT. I expect the same as well. Let me do on my own property WHATEVER I see fit as well. If you choose to make your property the most green environmentally freindly zone on earth, that is fine but I expect you to allow me to be the ANTI-THESIS of that if I SO CHOOSE for MY property. Basically I am a fiscally/militarily conservative Libertarian that NEVER wants my personal freedoms abridged upon toward some ill-concieved greater society-as-a-whole good. Our country was founded on the principle of Freedom with the Right to Life, Liberty, and the pursuit of happiness. Never is the caveat in the Constitution that those can be abridged due to mamby-pamby SAFETY although idiot politicians seem incorrectly to think so.

7) Many/Most of your posts offer GREAT value; just the cato and "call the manufacturer" ones sound like a "broken record" and offer little value.

[JStarStar]

I already corrected it without wasting my time. The document that points out how why this is a false-acronym is in my signature. You may continue to think the Earth is flat and that rockets "take off" or that a motor failure at or near the end of propellant burn or a missing ejection charge is at "take off", but I will not be forced to be "dumbed-down" or to stop speaking the truth.

Awesome, a link to a half-dozen guys sounding off with some variation of, "it is what is because I SAY IT IS, " and no other credible documentation other than their own thunderous reiteration of the fact that they consider themselves to be correct.

I know the whole history of the argument of "Cato" vs. "CATO" and I find neither argument conclusively persuasive. Ultimately I find the whole argument moronic as I find anyone who would spend extensive time attempting to document either side of it.

Two things however, are facts:

1) If the term "Cato" is intended as a contraction of the phrase "catastrophic failure," it must have been coined by illiterates, since the word "catastrophic" would of course have been more appropriately be contracted as "Cata"

2) While the contraction "Cato" does not match up with the supposed root word, the acronym "Catasrophe At Take-Off," in fact does.


Like 99.999999979% of all rocketeers everywhere I don't really give a flip where the term "CATO" came from, I know what it MEANS, which is, "abrupt unscheduled termination of rocket flight due to operational malfunction of propulsion unit." (teehee -- i don' t feel like getting into the intergalactic clash of 'engine' vs. 'motor' at the moment.)

Maybe we should just call it "AUTORFDTOMOPU" and be done with it.

[Shreadvector]

Combination meal is abbreviated as "combo", not "combi".

As clearly explained already in the document (no time wasted since it was typed a while ago and simply is there to point to and cut & paste from): "...rockets do not "Take off". Aircraft "Take Off", the McKenzie Brothers "Take Off" (eh?). Rockets "Lift Off" or if they are from the 1950's or 1960's they might "Blast Off".

Now onto the real world of engineering and rocket science. How about a satellite solid rocket or liquid engine that has a failure? They call it a "catastrophic failure". They do not "take off" - they are in or on their way to space and/or orbit when the failure occurs. The failure can occur at any point in the motor/engine burn. Many nozzle failures occur late in the burn. Ditto for casing failures...."

But, I understand that the information provided by others in the past (links on the PDF) are unimportant to those who wish to stick with the false acronym beleif. Any posted information by people who have been launching Model Rockets at the national level for 4 or 5 decades is unimportant when you must defend an error to the bitter end.
http://forums.rocketshoppe.com/showpost.php?p=59806&postcount=47
Almost as absurd as the folks who insist that an igniter failure is called a "burnout" instead of a "misfire". This one made it into Star Wars. http://www.jedisaber.com/sw/Sounds/STW41.wav

[LeeR]

OK, I've held off long enough. You are all wrong.

CATO is an acronym meaning:

Casing Anomaly, Thermic Overload

Fred, You have my permission to update your website with this information.

[Jerry Irvine]

Gosh, Fred,
A little OCD on the CATO definition, eh?
Let it go, man! Like the word 'hopefully' or further/farther, etc. I've read your treatise on CATO, BTW.
Blood pressure is a precious thing to waste.
Allen
Correct analysis of Fred.

Gee, I wish Ferd was on my arse about stuff all the time. Oh, wait!

:D

Jerry

[Jerry Irvine]

Combination meal is abbreviated as "combo", not "combi".

Really?

http://www.google.com/#hl=en&source=hp&q=combi+meal&aq=f&aqi=g8g-m1g-ms1&aql=&oq=&gs_rfai=C5nbpwulpTKvhN4PSiAPpocWICQAAAKoEBU_Q4B5I&fp=164c0eed268ae726

[Rocketflyer]

Correct analysis of Fred.

Gee, I wish Ferd was on my arse about stuff all the time. Oh, wait!

:D

Jerry


"Ferd?? :confused: Ferdinand Schecter? :chuckle:

[Jerry Irvine]

The acronym CATO has been reinterpreted over the years by a variety of styles of rocketeers from the originals from Germany, Sweeden, Glendale, CA, USA, etc. The wordy version "catastrophic failure" is a different thing referring to CATO.

It's a description.

CATO originally "meant" the thermic thing and was later repurposed into several others, all of which are now right because they all were used by different groups over the years. If we are really going to have an argument over which was first, you are going to have to find a hard drinking, over-smoking, rudely cussing guy who was active in the 40's and early 50's to get the real answer.

My school friend's dad, Mr. Datner of Aerojet hung out with folks like Von Karman, and most of the Gemini and Saturn team. He led the team that did the largest solid ever fired. He also wondered why people fixated on such trivia. "This is stuff we told stories about over drinks." "Shut up and build a **** rocket".

To me that really tells the story you need to know. Talk and tell stories all you want, but if you want to be a "real" rocketeer build something. It wouldn't hurt one little bit to cuss, drink way too much, smoke an annoying amount, then build a bigger one and tell stories about that one too.

Our rocket program was developed by some darn smart, fixated, roughians. perhaps that should be the lesson for the day.

Jerry

"Fire in the hole!"

http://v-serv.com/datner/Werner+Von+Braun+and+Dad.jpg

http://v-serv.com/datner/Datner4.jpg

http://v-serv.com/datner/Bradley+and+Dad.jpg

There's some history for you. :cool:

[ghrocketman]

Hard-drinking, over-smoking, and rudely cussing rocket designers huh ?
Sounds GOOD to me and I see NOTHING wrong with that.
I LIKE IT !!!!
No, I'm NOT joking either.
Any adults that have a problem with that should grow up and learn to deal with perfectly acceptable adult behavior and adjust their virgin ears and noses. :p

[Jerry Irvine]

You can't even post a direct quote from a historically relevant figure to this site without being censored!

We went to the same church here.

:D

Jerry

[jdbectec]

http://v-serv.com/datner/Datner4.jpg


Thanks for posting that! I didn't even realize they had test fired the 260 !

[Jerry Irvine]

I figure we could pitch in and order the third motor if it's only $3-10 million. A motor sufficient to launch a rather large space hotel for the cost of a mid-sized earthly mansion. Not bad.

Jerry

[STRMan]

Hummmmm...

I wonder.........

What would a B14 be without the core drilling? What would the impulse be?

What would the diameter and depth of the core have to be?

I would be MORE than happy to purchase B14's that were uncored.

:cool:

[blackshire]

I'm not 100% certain, but I think B14s without the drilled cores were B4 motors (although perhaps not identical to the purposely-made B4-2, B4-4, and B4-6 motors).

[STRMan]

I wonder how deep the core was and what diameter is was?

[Bazookadale]

I wonder how deep the core was and what diameter is was?

Well, I've got a 1969 B14 in front of me - the newer .500" ID. Using what I think is a 1/16" drill bit ( these old eyes can't make out the tiny markings but it looks 1/16" on a ruler) I drop it in and it fits with just a little wiggle room. It goes in about 1 3/16" from the base of the casing and I estimate that about 1/2" of that is the nozzle

[blackshire]

I wonder how deep the core was and what diameter is was?You're not...thinking about...home-brewing a B14 out of a B4...are you? (But if you are, I hope it works as well as the factory-made ones!)

[Doug Sams]

You're not...thinking about...home-brewing a B14 out of a B4...are you? I would start with a C6 rather than a B motor. By the time you drill the depth of a B14, I'm thinking there won't be much BP left above the core. That may no be a big deal on the delay motors, but on a booster (eg, B6-0), the coring process might drill right thru the grain. Hence, using a motor with a longer grain as a starting point.

(BTW, welcome back, Blackshire. Hope your trip was great.)

Doug

.

[blackshire]

I would start with a C6 rather than a B motor. By the time you drill the depth of a B14, I'm thinking there won't be much BP left above the core. That may no be a big deal on the delay motors, but on a booster (eg, B6-0), the coring process might drill right thru the grain. Hence, using a motor with a longer grain as a starting point.

(BTW, welcome back, Blackshire. Hope your trip was great.)

Doug

.Thank you, Doug! Yes, it was great fun helping out with the daily chores and the daily public "meet the horses" programs, as well as working on the preparations for their Mediaeval Day. Stuart Lodge (the UK's "G. Harry Stine," who founded the British Space Modeling Association) came over from Castle Donington with a case full of his international award-winning scale, parachute duration, and helicopter duration rockets, and the folks at the Northcote Heavy Horse Centre were so impressed that they would like to add model rocketry "Make it, Take it" build & fly and contest activities (spot-landing, "drag racing," etc.) to their Open House Days. Also (relevant to the B14), Stuart mentioned a friend of his who once made his own excellent-performing double-base propellant (nitroglycerin/nitrocellulose) model rocket motors until the UK government caught wind of his work. However, an ammunition factory possessing all of the permits and safety equipment could relatively easily produce double-base propellant model rocket motors as a side business for a secondary income stream. Maybe we could get B14s via that route?

[gpoehlein]

I would start with a C6 rather than a B motor. By the time you drill the depth of a B14, I'm thinking there won't be much BP left above the core. That may no be a big deal on the delay motors, but on a booster (eg, B6-0), the coring process might drill right thru the grain. Hence, using a motor with a longer grain as a starting point.

(BTW, welcome back, Blackshire. Hope your trip was great.)

Doug

.
I'm with Doug - I believe I read somewhere on one of these forums that the B14 was a core drilled C6, but I could be wrong. IF one were so inclined as to try to drill a C6, it would be most informative to put it on a test stand and compare it's thrust curve to that of the B14.

Just sayin'
Greg

[Bazookadale]

I'm with Doug - I believe I read somewhere on one of these forums that the B14 was a core drilled C6, but I could be wrong. IF one were so inclined as to try to drill a C6, it would be most informative to put it on a test stand and compare it's thrust curve to that of the B14.

Just sayin'
Greg


I have heard several people say that - look at a B14 and it is clearly NOT a C6 - the end cap is more than an inch down in the casing, about the same spot as any other B motor

I hope no one is serious about drilling their own - just not worth the risk.

[Jerry Irvine]

Well, I've got a 1969 B14 in front of me - the newer .500" ID. Using what I think is a 1/16" drill bit ( these old eyes can't make out the tiny markings but it looks 1/16" on a ruler) I drop it in and it fits with just a little wiggle room. It goes in about 1 3/16" from the base of the casing and I estimate that about 1/2" of that is the nozzle
I would like to see you go to a local machine shop QC dept. to have the core and nozzle and draft angles accurately measured.

Jerry

[Bazookadale]

Y'mean rocket science is more than my fingernail against the side of a drill bit transfered to a ruler? Gezzz

[STRMan]

Relax guys. I'm just wondering out loud here.

[Doug Sams]

I have heard several people say that - look at a B14 and it is clearly NOT a C6 - the end cap is more than an inch down in the casing, about the same spot as any other B motorHi, Dale,

I doubt it's a full C, but I think it has to be more than a standard B load to accommodate the deep core. I can't prove it, but I do know the old Estes catalogs listed higher propellant weight for the B14-0 than for the other B14's, presumably because they added some extra powder to prevent premature burn-thru.

So, if was playing around with coring - after I get my coring bunker with remote controlled tools built :D - I'd start with a C6 to make an ersatz B14 :)

Doug

.

[Bazookadale]

Hi, Dale,

I doubt it's a full C, but I think it has to be more than a standard B load to accommodate the deep core. I can't prove it, but I do know the old Estes catalogs listed higher propellant weight for the B14-0 than for the other B14's, presumably because they added some extra powder to prevent premature burn-thru.

So, if was playing around with coring - after I get my coring bunker with remote controlled tools built :D - I'd start with a C6 to make an ersatz B14 :)

Doug

.

depends what year catalog you have - the 1969 catalog lists the B14 and the B6 as having the same propellant weight - .220 oz or 6.24g and the B4 with more at .294oz or 8.33g

the 1967 catalog shows the old B3 and B.8 motors as both having .0139 lbs propellant

the interesting one is 1968 which does show a little more propellant in the B14-0- .01566lbs as opposed to .01374lbs for a B6 but only on the booster, so this must be to prevent premature blow through

[Doug Sams]

depends what year catalog you have - the 1969 catalog lists the B14 and the B6 as having the same propellant weight - .220 oz or 6.24g and the B4 with more at .294oz or 8.33g

the 1967 catalog shows the old B3 and B.8 motors as both having .0139 lbs propellant

the interesting one is 1968 which does show a little more propellant in the B14-0- .01566lbs as opposed to .01374lbs for a B6 but only on the booster, so this must be to prevent premature blow throughThe last one is the one I was citing. Looking at the 68 data, all the B6's, and all the B14's except the -0,had 0.01374 lbs.

As for the masses being the same in both B6 and B14, the one thought I had was that those numbers would be post drill numbers, right? Since pressure has little effect on Isp (for BP), the total propellant masses would be about the same for each B type regardless of thrust curve (assuming all the propellant is converted to woosh and doesn't get wasted by premature burn thru). But, because of the decidedly deeper core of the B14, they'd have to start with a deeper load of BP, wouldn't they?

Doug

.

[Shreadvector]

A Pre-drilled B14 might have a 'pinch' more BP, but certainly nowhere near a full C motor worth. They did not drill out half the propellant. :eek:

[ghrocketman]

+1 to what Fred just said; to keep the total delivered impulse the same as the B4/B6 engines they would have to add a "pinch" of propellant more during the ramming equal to the average mass of that drilled out. Total of a few milligrams at most.
If it had the same amount pre-drilled as the C6, the core would be 1/4" in diameter, it would burn in .035 sec instead of .35 sec, and would be like a B60 instead of a B14.

[Bazookadale]

If it had the same amount pre-drilled as the C6, the core would be 1/4" in diameter, it would burn in .035 sec instead of .35 sec, and would be like a B60 instead of a B14.

There's an idea!

[Doug Sams]

There's an idea!That's what I was thinking, too :D

Doug

.

[Doug Sams]

A Pre-drilled B14 might have a 'pinch' more BP, but certainly nowhere near a full C motor worth. They did not drill out half the propellant. :eek:Right, so if I were to core one, in my coring bunker :) I would want to start with the C since it has the needed pinch (and then some).

That is, since I can't very well ram a pinch into a B6-0, my next best option is to core a C6-0 (or C6-whatever). The gotcha is that, after the propellent reduced to end burning, I'd be left with a long, low tail ala the C5. (Unless I over-cored it, as GH suggested, into a B60 :D).

In all seriousness, this is all hypothetical. I like my fingers and eyes, and have no desire to take such risks, nor any inclination to build the aforementioned bunker. So, for now, it's all what if...

Doug

.

[blackshire]

Right, so if I were to core one, in my coring bunker :) I would want to start with the C since it has the needed pinch (and then some).

That is, since I can't very well ram a pinch into a B6-0, my next best option is to core a C6-0 (or C6-whatever). The gotcha is that, after the propellent reduced to end burning, I'd be left with a long, low tail ala the C5. (Unless I over-cored it, as GH suggested, into a B60 :D).

In all seriousness, this is all hypothetical. I like my fingers and eyes, and have no desire to take such risks, nor any inclination to build the aforementioned bunker. So, for now, it's all what if...

Doug

.Dr. Z (Dr. Jan Zigmund, see: www.rapier.cz/index.htm and www.minimakety.cz/rapier/other/Interview-2007/index-en.php ) in the Czech Republic produces 18 mm black powder model rocket motors as well as the Rapier motors (single-use, Jetex-like motors for F/F [Free Flight] model jet aircraft). If he produced B14 motors and got them NAR and CAR Certified, the large number of replies to this thread leaves no doubt in my mind that he would be able to sell all of the B14s he could make. Just "thinking out loud" here, if an "angel investor" or a group of such folk helped him (for example, if a lot of us each "chipped-in" a small amount of money to enable him to get the B14s certified), perhaps we could get B14 motors back into the hands of model rocketeers.

[Royatl]

Dr. Z (Dr. Jan Zigmund, see: www.rapier.cz/index.htm and www.minimakety.cz/rapier/other/Interview-2007/index-en.php ) in the Czech Republic produces 18 mm black powder model rocket motors as well as the Rapier motors (single-use, Jetex-like motors for F/F [Free Flight] model jet aircraft). If he produced B14 motors and got them NAR and CAR Certified, the large number of replies to this thread leaves no doubt in my mind that he would be able to sell all of the B14s he could make. Just "thinking out loud" here, if an "angel investor" or a group of such folk helped him (for example, if a lot of us each "chipped-in" a small amount of money to enable him to get the B14s certified), perhaps we could get B14 motors back into the hands of model rocketeers.


The problem would be importing. Just as it is now. There appears to be only one importer of the Rapier motors, and they are out of stock on everything. And I bet they can import them only because of their formulation.

Ask Old Rocketeer "II" what it takes to import black powder motors into the country

[Shreadvector]

Just a little bitty (MASSIVE) safety point that has not been mentioned yet by others:

Unless I'm wrong, I thought that Estes rammed the propellant slightly damp. I do not know what that means (I don't think that it is wet and runny, but it is not a dry powder).

Normal motors have to dry out or "cure" for a while before they pack them and ship them.

For the B14, it would have made sense that if there was a hand drilling operation (with tooling) that it would be done just after loading and before the curing or drying out has occurred.

If any of you drill an already dry motor, it may ignite much, MUCH faster than you expected. And with that drill bit crammed in there, where will the exploding bit fly off to? I'm guessing your "area", since that is probably in close proximity to the.

Please run a camera so we have a record of the events for future generations. Other people's future generations, that is.....:eek:

[STRMan]

Please run a camera so we have a record of the events for future generations. Other people's future generations, that is.....:eek:

At least for me, this is a highly theoretical discussion. But, just to play along...

IF I was to experiment on turning an end burning black powder engine into a core burner, I would NEVER use a power drill. I would gently use a drill bit in a hand drill and go very, very slowly with light pressure. Doing that, I could NEVER get near the temps necessary to ignite an engine.

Of course, this would NEVER lend itself to mass production, but I don't see how it is any more dangerous than when I read that some scrape the powder inside their upper stage engines to insure ignition when staging.

[Shreadvector]

People who know what they are doing do not "scrape the powder inside their upper stage engines". The people who understand how motors work and how upper stages ignite, simply look into the upper stage nozzle with a flashlight and if they see black/grey propellant they are ready to go. If they see white clay covereing the propellant, they use a wooden toothpick to scrape the softer clay away from the hard propellant face to expose the propellant.


They never dig into or scrape away the propellant. That would alter the centerbore and motor performance.

So, if you take a drill bit and hand drill the propellant, what is the local energy trnasfer like between the drill bit and propellant? No possibiltiy of it sparking or heating a microscopic particle to the ignition point?

You only need to get the reaction started. "exothermic"

[STRMan]

People who know what they are doing do not "scrape the powder inside their upper stage engines". The people who understand how motors work and how upper stages ignite, simply look into the upper stage nozzle with a flashlight and if they see black/grey propellant they are ready to go. If they see white clay covereing the propellant, they use a wooden toothpick to scrape the softer clay away from the hard propellant face to expose the propellant.


They never dig into or scrape away the propellant. That would alter the centerbore and motor performance.

So, if you take a drill bit and hand drill the propellant, what is the local energy trnasfer like between the drill bit and propellant? No possibiltiy of it sparking or heating a microscopic particle to the ignition point?

You only need to get the reaction started. "exothermic"

Maybe I should spray the drill bit with liquid nitrogen first, just to play it safe.

[Shreadvector]

Maybe I should spray the drill bit with liquid nitrogen first, just to play it safe.

You forgot to say "Maybe I should spray the theoretical drill bit with theoretical liquid nitrogen first, just to theoretically play it safe".

[Jerry Irvine]

Drilling black powder C6 and D12 motors is done all the time and, yes, with power drills. Most drill presses are belt driven with the motor protected by a dust cover to prevent dust from going near it.

The tiny amount of dust from the drilling of a BP motor cannot be worried about. Except by a paranoid. While it is true that if the drilling surface gets hot enough, the propellant could ignite, it is also true a certain mass must also reach that temperature.

So with BP as with all things machining, it is a matter of feed and speed. If the drill bit ever gets hot to the touch, simply pause for a few minutes. It won't. Drilling BP motors requires using a bore smaller than the throat, so the amount of material you remove is trivial.

My advise is if this process makes you nervous or paranoid, definitely do not do it. If the NAR safety code is your bond 24/7 with no exceptions, definitely avoid it.

But if you are inclined to safely experiment in an outdoor work area, you should be okay.

Jerry

[ghrocketman]

I have done what Jerry mentions in his above post and it has been fine for me; I would however NOT reccommend anyone else try it though...
Needless to say the NAR safety code has always been only of MINIMAL influence in all my rocketry activities since 1977.

[blackshire]

Agreed. Working slowly on a relatively high-humidity day (to avoid static discharges) with frequent pauses using a non-ferrous drill bit in a hand drill (a brace) works fine for drilling black powder. (This is how amateur pyrotechnicians such as Orville Carlisle made/make modifications and refinements to pyrotechnic stars, gerbs, and other charges.)

Regarding other "field modifications" to model rocket motors, it is not uncommon for Eastern European competitors to "fine-tune" ejection charges by removing some of the powder. In some cases, even the motors themselves are hand-rammed as Orville Carlisle made motors "back in the day."

[ghrocketman]

Unbelievable...some people actually hand-ram black powder motors and actually drill the cores without bellyaching/whining about some mamby-pamby safety code....for shame... :chuckle: :D

Seems like WE could take a page from THEM and BURN the majority of the mamby-pamby code...

In my book if I don't get permanently physically harmed the vast MAJORITY of the time by an activity, it is safe enough for me.

[blackshire]

Unbelievable...some people actually hand-ram black powder motors and actually drill the cores without bellyaching/whining about some mamby-pamby safety code....for shame... :chuckle: :D

Seems like WE could take a page from THEM and BURN the majority of the mamby-pamby code...

In my book if I don't get permanently physically harmed the vast MAJORITY of the time by an activity, it is safe enough for me.The only 100% totally safe activities are those we *never* engage in (if you never ride a horse, you'll never fall off his or her back or be bucked off), but such a risk-free life would be--to me--not worth living. The other extreme, wantonly taking risks (the equivalent of playing polo in the middle of a busy municipal freeway), while exciting and interesting to be sure, would be totally lacking in wisdom.

The intermediate path of taking carefully-calculated and planned-for risks is the prudent and worthwhile one, because it leads to progress in knowledge and experience while minimizing the dangers. In a model rocketry context, building a home-made hypergolic liquid bipropellant rocket engine would be a recklessly hazardous undertaking (one that would likely create a job *for* an undertaker!), but making 13 mm sugar propellant motors as described in detail in the Teleflite publication about them would not be a "basement bomber" activity.

[PaulK]

...Of course, this would NEVER lend itself to mass production, but I don't see how it is any more dangerous than when I read that some scrape the powder inside their upper stage engines to insure ignition when staging...A safer, and more reliable alternative, is to tamp a bit of 4F in the nozzle of the upper stage; Hypothetically speaking, of course.

[Ez2cDave]

Guys.

I asked Vern Estes at NARAM-50 about B14's and we had a pretty long conservation.

B14's started off life as C6 motors, which is why the B14's came in B14-0, B14-3, B14-5, & B14-7 "flavors" ( note the delays were the same as for C6's).

The drilling was done in TWO steps:

The CORE was drilled first, using a .080" bit . . . Then, a second drilling procedure enlarged the NOZZLE throat (Vern was a little "fuzzy" on the exact diameter ) and "countersunk" the propellant grain for a short ways. This increased the surface area and reduced the amount of BP to drop it into the "B" impulse range.

Dave

[Ltvscout]

Guys.

I asked Vern Estes at NARAM-50 about B14's and we had a pretty long conservation.

B14's started off life as C6 motors, which is why the B14's came in B14-0, B14-3, B14-5, & B14-7 "flavors" ( note the delays were the same as for C6's).

Centuri also made a B14-6. I have a shoebox-size rubbermaid full of them.

[jetlag]

Centuri also made a B14-6. I have a shoebox-size rubbermaid full of them.

Watch out, Scott:

GH may open his big ole wallet for some of those... :)

Allen

[Bazookadale]

Guys.

I asked Vern Estes at NARAM-50 about B14's and we had a pretty long conservation.

B14's started off life as C6 motors, which is why the B14's came in B14-0, B14-3, B14-5, & B14-7 "flavors" ( note the delays were the same as for C6's).

The drilling was done in TWO steps:

The CORE was drilled first, using a .080" bit . . . Then, a second drilling procedure enlarged the NOZZLE throat (Vern was a little "fuzzy" on the exact diameter ) and "countersunk" the propellant grain for a short ways. This increased the surface area and reduced the amount of BP to drop it into the "B" impulse range.

Dave

All you have to do is LOOK at a C6 motor and a B14 and you can easily see that the B14 did NOT start as a C6. Put a thin walled B14 next to a C6, B6, B4 and LOOK at them, you will see what I mean.If Vern told you this it is do to "fuzzy" memory of a man in his '80s .
I was flying core burning B motors in 1965, remember that the original "Mabel" could not make a C motor with delay and ejection charge because a B.8-6 filled the thick walled casing, so did the original B3/B14

Show me a reference to a B14-3 - they never made one but Estes did make a -5,-6,-7. After all they owned the machine and could set it to whatever delay they wanted

[Doug Sams]

Centuri also made a B14-6. I have a shoebox-size rubbermaid full of them.I have never been able to sort that out. Was there a rocket that just had to have that delay? Or was there a huge batch of -5's (or -7's) that tested long (short) so Centuri labeled and marketed them as -6's? Ie, Vern gave Lee a good deal on these? :D

Doug

.

[Doug Sams]

All you have to do is LOOK at a C6 motor and a B14 and you can easily see that the B14 did NOT start as a C6. Put a thin walled B14 next to a C6, B6, B4 and LOOK at them, you will see what I mean.I don't have any handy. What am I looking for?

Just picturing them in my head, I can't see why the nozzle on a C6 can't be bored to B14 shape. That is, we can always make the hole bigger :) (But going the other way is pretty tough ;) )

Doug

.

[Doug Sams]

Show me a reference to a B14-3...I suspect Dave confused it with the B8-3.

Doug

.

[ghrocketman]

The B8-3 was offered by Centuri for exactly ONE year; the same year Estes came out with the B8-5,7,0, but no -3.
Centuri offered the B8-3,5,7 but no -0.
I have never personally seen any B8-3 engines, but someone on the forum sent me a pic at one point.

Okay, Scott- are you willing to part with any of those B14-6's and can you ship ?
I'm HIGHLY interested !

[Doug Sams]

The B8-3 was offered by Centuri for exactly ONE year; 1981, according to my records...

BTW, I've staged a C5-0S to a B8-5. Thought you'd like that :)

Doug

.

[Shreadvector]

I don't have any handy. What am I looking for?

Just picturing them in my head, I can't see why the nozzle on a C6 can't be bored to B14 shape. That is, we can always make the hole bigger :) (But going the other way is pretty tough ;) )

Doug

.

B14 and C6 motors both used the new thin walled casing and had the same internal diameter.

A C6 motor is filled nearly to the top end of the motor casing.

A B14 is *NOT* filled to nearly the top end of the motor casing.

If a B14 started out as a C6 and had 5 Newton-second sof propellant drilled out of the nozzle end, it would still be filled to nearly the top of the motor casing. They were not.

I could certainly see them starting out as a "low C" motor, with a bit more propellant than a B motor initially loaded when the "precursor" motor is created prior to drilling it to the final B14 configuration.

Look at the pictures.

http://www.ninfinger.org/rockets/nostalgia/69estp76.html

[Doug Sams]

A C6 motor is filled nearly to the top end of the motor casing.Ah, good point. I wasn't picturing that end in my mind :)


If a B14 started out as a C6 and had 5 Newton-second sof propellant drilled out of the nozzle end, it would still be filled to nearly the top of the motor casing. They were not.

I could certainly see them starting out as a "low C" motor, with a bit more propellant than a B motor initially loaded when the "precursor" motor is created prior to drilling it to the final B14 configuration. I think that may be the source of a lot of the disagreement. I know I've stated C6 when I meant C6-like - same nozzle with more propellant than a B6. I agree that the coring process ain't gonna take out 5Ns/6g of propellat :)

Maybe the better term for the precursor is a B6+ (or B4+).

Doug

.

[Bazookadale]

I have never been able to sort that out. Was there a rocket that just had to have that delay? Or was there a huge batch of -5's (or -7's) that tested long (short) so Centuri labeled and marketed them as -6's? Ie, Vern gave Lee a good deal on these? :D

Doug

.

That never made sense to me either but Estes listed 5,6 and 7 second delays from 1966 -1971 both as B3-6 and B14-6

[Bazookadale]

B14 and C6 motors both used the new thin walled casing and had the same internal diameter.

A C6 motor is filled nearly to the top end of the motor casing.

A B14 is *NOT* filled to nearly the top end of the motor casing.

If a B14 started out as a C6 and had 5 Newton-second sof propellant drilled out of the nozzle end, it would still be filled to nearly the top of the motor casing. They were not.

I could certainly see them starting out as a "low C" motor, with a bit more propellant than a B motor initially loaded when the "precursor" motor is created prior to drilling it to the final B14 configuration.

Look at the pictures.

http://www.ninfinger.org/rockets/nostalgia/69estp76.html

Fred beat me in answering this - I should have been more specific in my post. Sorry, senior moments are happening more and more often :(

[shockwaveriderz]

B14's started out as modified B4's..they had an extra pressing or two of BP . they were then drilled to B14 specs. The B14 diagrams in the Estes catalogs are mere disinformation to throw off potential competitors.
The internal dimensions are exaggerated. (EDIT: the 68 Estes catlaog diagram is pretty accurate)

Same thing with the B3/B16.... they were also modified B4(b.8) although they were called Superr-B6 by MMI. These were Estes B4's made for MMI. The B.8-x motors were all actually B4
The actual B6's didn't appear until approx 1968 and were part of the new thinner cases and redesigned nozzles, as were the B14.


Everybody must be getting out and forgeting: all of this has been discussed in detail in previous Ye Old Rocket Shoppe postings......

Terry Dean

[Bazookadale]

If anyone has an old thick walled B3 motor they want to sell, and are going to TARC or NARAM this year drop me a line, I burnt my last one 30+ years ago and just need to have one! (no I won't trade my Eastern Ballistics motor though)

[Ez2cDave]

I suspect Dave confused it with the B8-3.

Doug

.


After looking at the diagram, I think that Vern was "crossed up" on it starting out as a "C" motor. I just reported what he told me at NARAM-50. I think he was right about the drilling operations, though.

At any rate, I sure wish that a high-thrust B motor was available.

Dave

[Bazookadale]

After looking at the diagram, I think that Vern was "crossed up" on it starting out as a "C" motor.

Dave
Unfortunately we are all getting older and our memories fade - wait did I already post that? :confused:

[Ltvscout]

Okay, Scott- are you willing to part with any of those B14-6's and can you ship ?
I'm HIGHLY interested !
Eventually I'll be selling a lot of stuff. I'm not setting any timetable though other than that it will be before Brianna starts college next fall. ;)

I've never had any qualms about shipping motors via parcel post.

[shockwaveriderz]

I think we need to be very careful and be very precise in asking questions of 70+ year old people about events that happened 50+ years ago.

The first B16 were demoed at NARAM-3 in August 1961. We know that because G. Harry Stine reported it in his NARAM-3 coverage. Perhaps it was originally intended to be a C motor and ended up as it did. And then perhaps the C.8-x motor came later. The earliest I can date a C.8-0 motor is late 1963 or early 1964. Anybody got a 1963 Estes catalog with an engine selection list in it? Or a Centuri 1963 catalog with an engine selection list?

According to Vern Estes from the Model Rocket New dated 32/3 1963, the B16 was changed to the B3:

"IF YOU WERE WONDERING about the change in Series II engines from В16 to В3
Whether the two "ere the same engine, or if there is a difference, you are entitled to a bit of explanation.
The two engines are the same.
The change came about for for several reasons.
The original В16 engines had a slightly higher peak thrust, but were less reliable, and sо they werе slоwed down a little.
The rest of the change came about by using static test equipment which was designed to handle the
thrust given by the Series II engines. Thе оriginal tests werе made with the stand designed for Series I engines,
and it just couldn't react fast enough to tell us exactly what the engine was doing.
When yоu consider that the thrust rises to over nine pounds aпd then drops back to zero in less than .35 second, the problem in measuring is understandable."

This seems to have taken place in late 1962.

The C,8-0 motor shows as being NAR certified as early as 6/1963 according to this old NAR report I have.


One thing I have learned over the past 10 years and interviewing REALLY old timers that are in their 70's and 80's is that you have to elaborate and fill in the blanks for their memory cells to start working sometimes. And even then you have to take the response with a grain of salt. There have been times when I asked the exact same question several times during an interview, and then asked followup questions and got differing responses.

Terry Dean

[Jerry Irvine]

One thing I have learned over the past 10 years and interviewing REALLY old timers that are in their 70's and 80's is that you have to elaborate and fill in the blanks for their memory cells to start working sometimes. And even then you have to take the response with a grain of salt. There have been times when I asked the exact same question several times during an interview, and then asked followup questions and got differing responses.

Terry Dean
At least you are doing first person interviews. That counts for something. A lot by my reckoning.

Jerry

[Carl@Semroc]

Eventually I'll be selling a lot of stuff. I'm not setting any timetable though other than that it will be before Brianna starts college next fall. ;)

I've never had any qualms about shipping motors via parcel post.
What are the date codes? Are they the "psuedo" B14's with the .140" throat or the older .186" thrroat with smaller port? I have GOT to put some of the Centuri newer B14's on a test stand to see how close they are to the older Estes B14's. I suspect they are "softer" with a tail, since that is what the simulation shows.

I agree that the B14 engines did not start as a C6. All that I have weighed have had from about 5-6 grams of black powder. Since the pressure is much higher, the specific impulse is also higher so it would take less BP than a B6. Since the throat is so large on the B4, the pressure is lower and it takes more (8 grams or so) of BP to reach the 5.0 N-sec desired impulse. All the Estes B14's I have (and some of the earlier Centuri) have the divergent section molded instead of drilled, so I do not think they started as anything but a B14. We had a separate die for the B14 that was nothing more than the divergent section. We drilled the throat first since it was much safer, then drilled the 1/16" port.

I have Centuri B8-3,5 and 7 (1981) and none have the thrust curves in the instructions.

[blackshire]

Carl, thank you for posting your B14 weighing and measuring results and for including information on your (Semroc) B14 motors. It gave me an idea:

If you still have enough technical documentation to enable production of the Semroc B14s, you could contract the production (under license) to a German, Czech, or (perhaps) Chinese model rocket motor manufacturer for sale in overseas markets, whose legal & regulatory requirements (especially in Central Europe and Eastern Europe) appear to be much less strict than ours. You all would make money from sales of the motors, and if they sold well enough you might have sufficient excess funds to tackle getting them NAR & CAR Certified and otherwise accepted for sale in the United States and Canada.

[Ltvscout]

What are the date codes? Are they the "psuedo" B14's with the .140" throat or the older .186" thrroat with smaller port? I have GOT to put some of the Centuri newer B14's on a test stand to see how close they are to the older Estes B14's. I suspect they are "softer" with a tail, since that is what the simulation shows.
They are in the old original, orange/black/white boxes. I don't have any easily accessible to look at date codes or throat size unfortunately.

[shockwaveriderz]

I think but I'm not 100% sure that the older or original B14 used essentially the same nozzle dimensions and the machine drilled core and at some point in the early 1970's , the nozzle core changed to a molded one. I think one of the reasons for this was that the BP changed from the Dupont BP that had been used by Estes since the beginnings , Dupont plants had several explosions in the late 60's early 70's and Dupont stopped production for a whil(EDIT: for commercial not military customers)e and Estes had to change to Canadian CIL powder which wasn't as powerful as the original DuPont Powder. (EDIT: actually it was a slower burning powder for a given Kn) By the mdf 70's Dupont sold out completely to Goex. For a good intro to Kn see this:

http://www.thrustgear.com/topics/Kn_Notes.htm



"GOEX had long supplied Estes Industries with black powder for use in model
rocket motors. GOEX claims that all of the black powder they had imported from KIK,
in Slovenia, had been sold to fireworks powder customers. No doubt Estes had been
shipped KIK powder while GOEX was trying to get the black powder plant near Minden,
LA up and running. In 2002 we again see containers of KIK made black powder arriving
in the U.S. and Estes was not the only company importing it."

2002 November 33,000 pounds at $2.85 per pound, landed duty paid value.
2003 June 34,375 pounds at $2.88 per pound, landed duty paid value.
2004 May 34,375 pounds at $2.67 per pound, landed duty paid value.
August 34,045 pounds at $2.76 per pound, landed duty paid value.
November 29,414 pounds at $3.54 per pound, landed duty paid value.
2005 January 34,375 pounds at $2.49 per pound, landed duty paid value.
2006 January 36,401 pounds at $2.54 per pound, landed duty paid value.
2007 April 23,971 pounds at $4.00 per pound, landed duty paid value.


The November 2004 container and the April 2007 container were imported by
Western Powder Company. One of GOEX’s master distributors. These two containers
were rifle powder packed in tin cans at the KIK plant. The other containers represent
bulk packaged powder ordered by Estes Industries for in-house use in model rocket
motors.
The January 2006 shipment to Estes was their last order to the KIK plant in
Slovenia. GOEX recovered that business by lowering the price of their powder to Estes
Industries.


Terry Dean

[shockwaveriderz]

What are the date codes? Are they the "psuedo" B14's with the .140" throat or the older .186" thrroat with smaller port? I have GOT to put some of the Centuri newer B14's on a test stand to see how close they are to the older Estes B14's. I suspect they are "softer" with a tail, since that is what the simulation shows.

I agree that the B14 engines did not start as a C6. All that I have weighed have had from about 5-6 grams of black powder. Since the pressure is much higher, the specific impulse is also higher so it would take less BP than a B6. Since the throat is so large on the B4, the pressure is lower and it takes more (8 grams or so) of BP to reach the 5.0 N-sec desired impulse. All the Estes B14's I have (and some of the earlier Centuri) have the divergent section molded instead of drilled, so I do not think they started as anything but a B14. We had a separate die for the B14 that was nothing more than the divergent section. We drilled the throat first since it was much safer, then drilled the 1/16" port.

I have Centuri B8-3,5 and 7 (1981) and none have the thrust curves in the instructions.


Carl:

which B14's that you have , have the .140 throat? Reading through the Estes and Centuri catalogs and Doug Sam's fine Centuri-Estes Motor History Lineage, Estes stopped showing internal diagrams of their engines in 1970. I guess Damon thought this was giving away the crown jewels so to speak.

If you look at the 66-67 catalogs, the (B3)B14's had the .1875 or .186" core as you described. The 68-70 catalogs show a .165" core..... and the peak thrust goes from 9lb(thats 40 Newtons!) to 7 lb(31N) while the thrust duration stays the same at .35 s.

Also the catalogs/Sams indicate that Estes stiopped selling their B14 in 1979.....and Centuri continued to sell what I will call, the leftover Estes B14's that were just relabeled under the Centuri name, as by 1979-81 Centuri had been absorbed and moved to Penrosefrom Phoenix. So there should not have been any difference between the Estes and Centuri B14's as they weer all made by the same manufacturer: Estes.

Or are you saying the B8's had a .140" throat?

Doug Sams once provided me with an overlay of the C5/B8 thrust time curves....Doug? As the B8 was the result of the successful C5; but the B8 max thrust was way down to only 22N which was a little over half of the original B3 specs.....

here's Doug's B8-C5 Thrust time curves:

http://forums.rocketshoppe.com/showpost.php?p=39617&postcount=3


Terry Dean

[Carl@Semroc]

Carl:

which B14's that you have , have the .140 throat? I only have 2, both dated 8L10 (Oct 1979) and were made by a Mabel in Penrose (almost certain). I don't think I have any B14's made on Centuri machines and I don't ever remember seeing one. I had to take one apart to measure the actual throat and it is .161" instead of .140". Since the drift is slanted, it is almost impossible to measure the actual throat non-destructively.

The Estes and Centuri B8's and C5's that I have from that same period were almost certainly made in Penrose as well. They have a .136" throat. Later date codes have the white clay and have a .120" throat. :confused: (erosion?)

All of these are pressed with no post drilling unless they used a tapered bit. This would be HIGHLY unlikely, because it would lead to even more overheating during the drilling operation.
If you look at the 66-67 catalogs, the (B3)B14's had the .1875 or .186" core as you described. The 68-70 catalogs show a .165" core..... and the peak thrust goes from 9lb(thats 40 Newtons!) to 7 lb(31N) while the thrust duration stays the same at .35 s.Looking at the B14's I have from various periods, they seem to have the two step drilling with the .186" throats and the .161" or .165" throats are undrilled. Has anyone got any Estes B14's that are not drilled?

Doug Sams once provided me with an overlay of the C5/B8 thrust time curves....Doug? As the B8 was the result of the successful C5; but the B8 max thrust was way down to only 22N which was a little over half of the original B3 specs.....I am almost positive the B8 and C5 were sister engines with the same tooling, just different BP amounts. When I saw the Centuri B14's, I though they were also made with that tooling. It is a deeper port, so it could not be the same. I still suspect that the thrust curve for the Centuri B14 is closer to a B10 or B11.

The comments about the different energy black powder formulations and their impact are well-taken. We noticed that back in the early days even when though all the black powder we ever used was from duPont. Probably a different grove of trees or different time of harvesting. The early powder seemed to be better than the new Goex, but it could just be nostalgia or better instruments.

When Ed writes his book we won't have to keep guessing!

[LeeR]

Here are side-by-side B14 vs. C5 nozzle pictures. I bought a number of these, in the store packaging shown. I also have some Estes and Centuri B14s from 1969. They look the same, and label is the same, other than company and address. You can definitely tell they were made in the same factory. I'll take some pics of those and post.

http://i265.photobucket.com/albums/ii220/hobbes_pics/Centuri/th_centuri-01.jpg (http://s265.photobucket.com/albums/ii220/hobbes_pics/Centuri/?action=view&current=centuri-01.jpg)http://i265.photobucket.com/albums/ii220/hobbes_pics/Centuri/th_centuri-02.jpg (http://s265.photobucket.com/albums/ii220/hobbes_pics/Centuri/?action=view&current=centuri-02.jpg)http://i265.photobucket.com/albums/ii220/hobbes_pics/Centuri/th_centuri-04.jpg (http://s265.photobucket.com/albums/ii220/hobbes_pics/Centuri/?action=view&current=centuri-04.jpg)

[Bazookadale]

I had forgotten that after they ceased production of the original Enerjet motors they used that name for their black powder line. Another senior moment.

[Carl@Semroc]

Here are side-by-side B14 vs. C5 nozzle pictures. I bought a number of these, in the store packaging shown. I also have some Estes and Centuri B14s from 1969. They look the same, and label is the same, other than company and address. You can definitely tell they were made in the same factory. I'll take some pics of those and post.

http://i265.photobucket.com/albums/ii220/hobbes_pics/Centuri/th_centuri-01.jpg (http://s265.photobucket.com/albums/ii220/hobbes_pics/Centuri/?action=view&current=centuri-01.jpg)http://i265.photobucket.com/albums/ii220/hobbes_pics/Centuri/th_centuri-02.jpg (http://s265.photobucket.com/albums/ii220/hobbes_pics/Centuri/?action=view&current=centuri-02.jpg)http://i265.photobucket.com/albums/ii220/hobbes_pics/Centuri/th_centuri-04.jpg (http://s265.photobucket.com/albums/ii220/hobbes_pics/Centuri/?action=view&current=centuri-04.jpg)
Your Centuri B14-0 appears to be the same date code as mine, 8J10.

[LeeR]

Carl,

Yes, they are 8J10, and according to my magic decoder spreadsheet, that is 1979. The thing that amazed me was the fact that the B14-0 is about half full. Sure would have been cool to have a fully loaded casing, and I'll bet someone at Estes must have tried that, for grins. :)

Like Dale, I've got a senior moment thing going. For the life of me I cannot remember when or where I bought these. I was going to fly one this summer, and I only got out to one launch so far this entire year -- SAD!

[Carl@Semroc]

Carl,

Yes, they are 8J10, and according to my magic decoder spreadsheet, that is 1979. The thing that amazed me was the fact that the B14-0 is about half full. Sure would have been cool to have a fully loaded casing, and I'll bet someone at Estes must have tried that, for grins. :)

If it was completely full with the same port depth, it would not be a full C, probably. The tail would have such low pressure, the thrust would also be very low.

If it was drilled the full length, it would probably be a C30 or so. We never could drill that deep successfully. We did prototype 3/4C19 engines that had 7.5N-sec. I don't remember doing any except 3/4C19-0 booster, but they were even more impressive than the B14's.

[ghrocketman]

Carl,
How bout bringing back that 3/4C19-0 seeing as nobody else wants to make core-burning BP engines ?
You would sell a ton.

[LeeR]

Carl,
How bout bringing back that 3/4C19-0 seeing as nobody else wants to make core-burning BP engines ?
You would sell a ton.

I'm ready to pre-order!

[ghrocketman]

You and me both, buddy !
I'd order 100 tomorrow if I could.

I wish Estes would stop being such mamby-pambys regarding port burning motors.
GIVE YOUR CUSTOMERS WHAT THEY ARE ASKING FOR, without any dawg-crap excuses of why not; JUST DO IT !!!
If they were safely made way back in 1965, they CERTAINLY can be now.
Everybody knows what excuses are like; %!$hole$; everybody has one, and THEY ALL STINK !!!

Just amazes me that Aerotech can give us more than a dozen totally new motors in ONE year, but getting Estes to resume production of a previously existing motor is less easily done than turning Lead into Gold.

[Carl@Semroc]

I'm ready to pre-order!
Maybe we do not actually have to make any. There was a time that Estes-Cox was saying they would never re-release any of the old Centuri kits. They have recently released several of the kits after we posted them on our site as "Coming Soon". Maybe we just need to do a page of engines on our site with the B14-0 and 3/4C19-0 listed as "Coming Soon". :chuckle:

[Doug Sams]

Maybe we do not actually have to make any. There was a time that Estes-Cox was saying they would never re-release any of the old Centuri kits. They have recently released several of the kits after we posted them on our site as "Coming Soon". Maybe we just need to do a page of engines on our site with the B14-0 and 3/4C19-0 listed as "Coming Soon". :chuckle:Well, make sure you put the D30 and ¾E40 on there while you're at it :D

Doug

.

[Jerry Irvine]

Just amazes me that Aerotech can give us more than a dozen totally new motors in ONE year, but getting Estes to resume production of a previously existing motor is less easily done than turning Lead into Gold.
Except the lead to gold part. Estes has a very different criterion for product release than Aerotech does. AT can release a product with a low marginal R&D cost, sometimes consumer funded R&D, let it succeed or fail in the marketplace all at a cost which is fully recovered when even the failed units sell. If it fails the net cost to them is near zero. A success is measured in hundreds of units and thousands of dollars per type.

Estes on the other hand has to sell 20,000 3-packs a year to even consider it. They have to sell them at a far steeper discount (20%+ more) than Aerotech ever does, and they have to cover higher salaries. Now Estes has the advantages of lower COGS, and far better distribution, and far faster product ramp than the other guy, but if they do make a motor that sits on the shelves like the D11-P did, it slows down the money flow from its dealers for faster moving products like Big Bertha's and B6-4's.

So I think the compromise that works is for someone like Hangar 11 to buy a run of motors outright. You simply have the problem that you need Estes more than they need you on the B14 front, they have said that product is dead and they do mean it, and you are whining.

Carl no longer makes motors or he would have made the A8-5 himself and made serious money on not much production hassle.

Your options are loud whining or secret whining, but not B14's. :D
I suspect you will not employ your option of no whining.

Jerry

[ghrocketman]

I will CONTINUE to push for the B14 or something like it ad nauseum until someone responds affirmatively BY ACTUALLY PRODUCING THEM to the point of sounding like a broken record.
DEAL WITH IT !
I for one am sick of the only new BP SU motors that EVER come out are long-burn weak-thrust motors that NOBODY is ever clamoring for.

I like Carl's idea.
Put them up on the Semroc website as a catalogued item.
That may be enough to get Estes to produce them.
If that was the case, I'd buy strictly from Semroc if they actually made them.
It would really piss me off if the only reason Estes was to produce them was because a competitor chose to also instead of customers requesting them.

I think the simplest way is for me to use a good ol' fashioned drill bit on a B4-2 or B4-4

Why a company would not produce something that would obviously sell is BEYOND ASININE; it is flat out IDIOTIC !

[PaulK]

Today, I flew a pair of "F" date code Estes B14-7 motors in a Deuces Wild. Sometimes you've just gotta say, "what the heck!".

[blackshire]

Maybe we do not actually have to make any. There was a time that Estes-Cox was saying they would never re-release any of the old Centuri kits. They have recently released several of the kits after we posted them on our site as "Coming Soon". Maybe we just need to do a page of engines on our site with the B14-0 and 3/4C19-0 listed as "Coming Soon". :chuckle:I'm with ghrocketman (and you) on this, Carl. If core-burning black powder motors could be produced safely in 1965 using the less-advanced technology of that time, there is no reason why they couldn't be made today at a lower unit cost (accounting for inflation, of course) than they were back then.

Your "Coming Soon 'threat'" need not be an idle one, either, as a Chinese factory or perhaps Dr. Z (Dr. Jan Zigmund) in the Czech Republic could make the Semroc-design B14s and 3/4Cs under license to you for sale (initially) in Europe, then later in the USA and Canada. Who knows--maybe the CAR (many of whose members have European rocketry connections) might even beat the NAR by moving to certify your license-made Semroc B14 and 3/4C motors in Canada first?

[blackshire]

Whatever you do regarding this, Carl, I'd love it if you referred to the Semroc motors in the ad copy (and on the Semroc web site) as "Propulsion Modules," your original name for your motors (which was even printed on their casings). It was a stroke of genius not only because the name was different (and thus differentiated your motors from other firms' motors), but also because it didn't connote possible danger to potential vendors. (In 1997, Korey Kline told me that he named his rocket company [which was located in the middle of the Miami, Florida industrial warehouse district] Environmental Aerosciences because the name didn't connote danger to anyone since it didn't contain the word "rocket.")

[STRMan]

I wonder what 7 B14's would look like lifting a Semroc Hydra 7 off the pad!

[LeeR]

Explosive? :)

But please. someone do it, and video the launch! :)

From past personal experience, I'd be nervous. I flew a Flying Jenny glider as a kid on a B14. It did exceed the speed of balsa ...

[blackshire]

I wonder what 7 B14's would look like lifting a Semroc Hydra 7 off the pad!*GLORIOUS!*

[blackshire]

Explosive? :)

But please. someone do it, and video the launch! :)

From past personal experience, I'd be nervous. I flew a Flying Jenny glider as a kid on a B14. It did exceed the speed of balsa ...With few exceptions, 18 mm motor powered boost-gliders should *never* use motors with average thrust levels of more than 6 or 7 newtons--any more is asking for trouble (as in removing the gliders' wings during powered ascent). The B14 was made for entirely different purposes--boosting heavy, often "draggy" rockets such as large scale models and multi-stage rockets, as well as large payload-carrying models.

[ghrocketman]

SEVEN B14's in a Hydra 7 would be a sight to behold !
It would be the equivalent of a ~35n-sec E98 !

I think a B8 would shred a Flying Jenny, let alone a B14.

[danfrank]

Hi, I have a Hydra 7 that I use for a Cineroc carier. If somebody has the B14's I have the Hydra 7 and Cineroc....
I live in the LA California Area but visit Houston Texas often.
Daniel

[Jerry Irvine]

Hi, I have a Hydra 7 that I use for a Cineroc carier. If somebody has the B14's I have the Hydra 7 and Cineroc....
I live in the LA California Area but visit Houston Texas often.
Daniel
Would 18mm E10's do the trick?

:D

[ghrocketman]

I once launched an Astron Scrambler with an empty payload on 3xB14-5.
I think it hit Warp-4 in about 0.2sec.

[kurtschachner]

I have some B14-6 engines too, somewhere. I few a couple a long time ago but IIRC I got several boxes from the same place you did. I will see if I can find them in my (lesser) stash of stuff.

They are in the old original, orange/black/white boxes. I don't have any easily accessible to look at date codes or throat size unfortunately.

[Ltvscout]

I have some B14-6 engines too, somewhere. I few a couple a long time ago but IIRC I got several boxes from the same place you did. I will see if I can find them in my (lesser) stash of stuff.
Ya, I couldn't believe how cheap they were selling them. Like around $2/box or something if I recall.

[ghrocketman]

WOW ! That's a darned good price in 1975, let alone now !

[Jerry Irvine]

B14's are dead and not coming back. RIP and get over it.

However if Estes were to start using a new partially plastic propellant, it might be possible for the 18mm B14 and the 24mm D40 and the new 29mm F60.

[ghrocketman]

I want any company to GROW A PAIR, stop citing BS safety reasons, and actually make CORE-BURNING BP motors again. NOTHING LESS will do. I'm confident someone eventually will. Until then there's the limited old stock I have, along with the possibility of 'hand porting' B4-2's, 4's, and 6's. No way currently to recreate the old B14-0 in one simple step.

[blackshire]

I want any company to GROW A PAIR, stop citing BS safety reasons, and actually make CORE-BURNING BP motors again. NOTHING LESS will do. I'm confident someone eventually will. Until then there's the limited old stock I have, along with the possibility of 'hand porting' B4-2's, 4's, and 6's. No way currently to recreate the old B14-0 in one simple step.Sky in China could make black powder B14 motors; since they also make and sell full-scale solid propellant rockets (including anti-hail rockets) in large quantities, they would be in a financial position to get such B14s in production and certified for sale in the U.S. and Canadian markets.

[JStarStar]

"Hand-porting" existing B motors, of course, is an egregrious violation of the MRSC, if you care about that sort of thing.

And of course one of the very reasons the major manufacturers don't want to mess with them is the fairly high frequency of things going wrong -- when you try to drill holes in BP propellant grains, regardless of whether your drill bit is made of metal or plastic or whatever, it tends to heat up -- and when things heat up inside BP grains bad things tend to happen.

[sandman]

I use to fly a lot of B14 motors when they were available back in the 60's.

When the C6 motors finally became available I gladly switched and never looked back.

The B14 motor was a useless POS good for one thing, striping balsa fins off rockets!

Rockets would take off so fast even if the fins stayed on you couldn't see where they went.
0.07 sec burn was just dumb!

No great loss!

A truly useless motor!

[kurtschachner]

What?!? It was the perfect motor for a Farside, or a Delta/Camroc or anything else that was heavy.

Wow, you're dead to me now.


The B14 motor was a useless POS

A truly useless motor!

[blackshire]

"Hand-porting" existing B motors, of course, is an egregrious violation of the MRSC, if you care about that sort of thing.

And of course one of the very reasons the major manufacturers don't want to mess with them is the fairly high frequency of things going wrong -- when you try to drill holes in BP propellant grains, regardless of whether your drill bit is made of metal or plastic or whatever, it tends to heat up -- and when things heat up inside BP grains bad things tend to happen.It could be done safely by means of automated, numerically-controlled equipment, especially if the motors were drilled in small batches at a time. The motors could be mounted firmly in tubes held precisely in a vertical rack, in a row of perhaps fifty motors. A drill could move along a vertical track spaced a few inches away from the motor rack. The drill--which would have a steel plate jet deflector around the base of the chuck, to protect the electric motor's casing from a motor's exhaust plume--would move down its track, drilling out each motor in turn. A smaller jet deflector at the base of the drill bit would protect the drill's chuck from motor exhaust. Also:

The motors would be loaded into their mounting tubes with all power OFF, and then the numerically-controlled track drill would be started after all personnel had vacated the motor-drilling facility (which could be a small shack patterned after Estes' Mabel buildings). By having no more than fifty motors in the facility at any one time, the results of even a worst-case accident (all fifty motors igniting in rapid succession) would be merely annoying rather than tragic. Any model rocket motor manufacturer could set up such a B14 "post-production" line. The insurance and motor certification costs would likely cost more than the equipment itself, which is why a large, less-regulated overseas rocket manufacturer like Sky in China (which makes many full-scale rockets as well as model rocket motors & kits) could more easily make B14 motors.

[ghrocketman]

Me thinx Sandman must have been snorting too much sawdust and glue to make such a blasphemous statement about the B14. If it stripped the fins off your rockets, you used either too weak of a grade of balsa, or crappy glue joints. My Astron Scrambler has flown more than once on a cluster of 3xB14-5 with ZERO ill effects. That's the equivalent of a 15n-sec D45-5 !

As far as the MRSC banning 'hand porting' or any modification of SU motors, 1) no I don't care, and 2) it's high time that rule was COMPLETELY ELIMINATED from the code whatsoever.
NOT JOKING !

By the way, the VERY OLD B3 was the motor with the .07 sec burn time. The B14 was .35 sec.

[rocketguy101]

The drill--which would have a steel plate jet deflector around the base of the chuck, to protect the electric motor's casing from a motor's exhaust plume--

pneumatic (air-powered) drills would reduce fire issues. they could be NC controlled.

I really miss B14s!!!!

[ghrocketman]

I agree that there are multiple different modern methods to make port-burning 18 and 24mm SU BP motors safely. The EXCUSE from 'the big E' regarding safety simply holds ZERO water or validity. Hopefully someone SOON can step-up and fill this REAL need. Too bad the only other current 'semi major' player in SU BP motors does little other than offer 'me too' motors often at HIGHER cost instead of needed motors NOT offered by the 'big E'.

[blackshire]

pneumatic (air-powered) drills would reduce fire issues. they could be NC controlled.Yes--the electrical wiring (for the air pump) and the pump motor could be located in a separate building or a fire-proofed room in the motor-drilling building.I really miss B14s!!!!I never got a chance to try one! By the time I could buy my own motors, the B8 and C5 were all that were available.

[Shreadvector]

You are all ASSuming that the fire hazard is from the drill drive and not from the drill bit engaging the propellant.

If it could be done safely at a profit it would be. Nobody walks away from profit.

[ghrocketman]

The semi-ported B8 and C5 were darned near as good as the old B14.
Even those back would be greatly appreciated !
Not quite the B14 lifting power, but a ton better than the current B4-B6-C6 lineup we have now.

[ghrocketman]

It was done safely ENOUGH back in the 60's and 70's.
Manufacturing (drilling) them in batches of 50 to 100 via CNC machine in an UNMANNED building would be perfectly safe. If there is an incident, nobody is in the bldg, and we are only talking like 3lbs of propellant MAX. Big Deal. They are feeding LAME-O EXCUSES and nothing more.