Other Requests/Ideas

[Ltvscout]

I'm starting this thread for requests/ideas other than motors or kits.

Something that would be nice to see is a parts assortment pack like they had in the good old days. The assortment pack from Estes nowadays is a joke with leftover parts in it. There are companies like Red Arrow, BMS, Apogee and Flis offering partial parts assortments, but nothing like the complete assortments that Centuri and Estes use to offer in the late 60's.

[CPMcGraw]

I'm starting this thread for requests/ideas other than motors or kits.

Something that would be nice to see is a parts assortment pack like they had in the good old days. The assortment pack from Estes nowadays is a joke with leftover parts in it. There are companies like Red Arrow, BMS, Apogee and Flis offering partial parts assortments, but nothing like the complete assortments that Centuri and Estes use to offer in the late 60's.

Oh, thank you, Scott!

I've been going back to the old catalogs and just drooling longingly for some of those parts packages offered back then. What we need is a good "supply replenisher" box of usable tubes and balsa and rings and, well, STUFF that we really need...

[Ltvscout]

Oh, thank you, Scott!

I've been going back to the old catalogs and just drooling longingly for some of those parts packages offered back then. What we need is a good "supply replenisher" box of usable tubes and balsa and rings and, well, STUFF that we really need...
I'm talking a complete set. Take a look at page 53 of the '69 Centuri catalog. The Experimenters Special had EVERYTHING you needed to make up to 8 rockets. Now that's an assortment!

[CPMcGraw]

I'm talking a complete set. Take a look at page 53 of the '69 Centuri catalog. The Experimenters Special had EVERYTHING you needed to make up to 8 rockets. Now that's an assortment!

Agreed!

[Carl@Semroc]

OK. Which one first?

[CPMcGraw]

OK. Which one first?

If you mean "Which style -- Centuri or Estes?", then I'd have to say Centuri style, since there's a better cross-section of sizes.

If you mean "Which quantity of material in the package?", then I'd have to agree again with Scott; we need a comprehensive selection of components to make it interesting. I don't know which would be the better way to package tubes -- make them all 18", or a selection of long and short. Nose cones and other turned items, enough to build 8-10 basic models. Same with the other components like rings, launch lugs, motor hooks, parachutes, etc...

And we can't forget the printed materials, like fin patterns and shrouds, maybe even a complete plan of some simple design to get builders started.

It might be possible to feature two or three different "price range" kits, just like Estes and Centuri did in the late 60s. One set might have enough for 2-3 models, one might be able to do 3-5 models, the third as many as 8. I think folks would pay a premium for good quality components, but what they want is consistency.

Price points? How about $25, $40, and $75? What could these boxes be filled with for those prices? Close to what I described above? Better? Spot-on?

Maybe even put together at some point a $100 Super Box, equal to 2 or 3 times the $75-size box, considering that there would be a reduction in some of the printed material as a cost savings...

[James Pierson]

A better parts asortment would be great and a Futuristic Parts Assortment would be even better.

Also I would also like to see a Rocket Designing Kit. Not a parts assortment but a sample of all Semroc body tubes, center rings, fin material, various dowels, LL, and other parts.

*Body tube samples would be precut and about 1/2" long with several of each tube.
*Fin material sample would be of various thicknesses from 1/16" to 1/8".
I use such a Design Box myself and has really helped me figure out what tubes fit into each other in an eye appealing way. I lay several tubes on a flat surface and design via End View of the rocket design. I have come up with several design in this way including the Cargo Star Transport, Megga Dogfighter, Etc...


Parts:
I also would like a better way to attach a paper transition to a body tube. The narrow of the
transition is easy but the wider end onto an .05 CR really stinks :( . I would like to see some 1/4" thick Balsa Transition Centering Rings for some commomly used paper transitions. Half (1/8") of the ring would be used as a centering ring to center the two different BT's and the other half (1/8") would be tapered to match the slope of the paper transition. A designer could even customize the slope themself with a little sanding if an oddball transition is desired.


James Pierson
NAR# 77907

[CPMcGraw]

Parts:
I also would like a better way to attach a paper transition to a body tube. The narrow of the
transition is easy but the wider end onto an .05 CR really stinks :( . I would like to see some 1/4" thick Balsa Transition Centering Rings for some commomly used paper transitions. Half (1/8") of the ring would be used as a centering ring to center the two different BT's and the other half (1/8") would be tapered to match the slope of the paper transition. A designer could even customize the slope themself with a little sanding if an oddball transition is desired.

James,

Carl has demonstrated this to be possible with paper rings using the laser Krellvenator and his 0.05" paper stock. Look at the base ring on the Apollo capsule. It's a staggered cut. For a ring like you're describing, a glue-up of two rings - one tapered, one not - would work fine. If the paper stock were available in thicker sheets - up to 1/4" (or 5x the 0.05" material, for 0.25" thick) - your ring could be done the same way.

[rocket_james]

I'm starting this thread for requests/ideas other than motors or kits.

Something that would be nice to see is a parts assortment pack like they had in the good old days. The assortment pack from Estes nowadays is a joke with leftover parts in it. There are companies like Red Arrow, BMS, Apogee and Flis offering partial parts assortments, but nothing like the complete assortments that Centuri and Estes use to offer in the late 60's.
My personal preference on those is to have larger packs of single items, rather than packs of varied items. I always end up with stuff that I just use up on something just to use it up. I also prefer the larger 34" tubes, rather than 18" tubes. Getting rid of the spirals is a good thing, too! Who likes filling spirals. Can't we just get rid of them? I got a couple of boxes of 34" tubes (BT-5 thru BT-60, 12 of each per box) from a guy on eBay and the spirals are almost non-existent. That's my idea of a parts pack! Having a variety of bulk packs like that would be great. A variety pack for cones would be cool, though, especially one that included futuristic cones like the Estes Futuristic Parts Assortment.
My 2 cents.
James

[foose4string]

Good idea Scott. There are some parts I don't mind making from scratch, tubes and cones are what is most important to me, the rest I can usually fabricate myself in a pinch. Only problem with including cones, is your stuck using what you have rather than what you really want. Tube assortments are a good place to start.

[CPMcGraw]

Good idea Scott. There are some parts I don't mind making from scratch, tubes and cones are what is most important to me, the rest I can usually fabricate myself in a pinch. Only problem with including cones, is your stuck using what you have rather than what you really want. Tube assortments are a good place to start.

Keep in mind, this package is aimed at individuals who don't have a lathe to cut their own parts. It really is just "a starting point"; it's a way to get a few quality parts into their hands and allow them to get going on some simple projects. Once they have the package, they will be directed to the SEMROC website for additional components. Think of this package as an appetizer before dinner; it's just enough to whet the appetite, and not enough to spoil it.

[Doug Sams]

Keep in mind, this package is aimed at individuals who don't have a lathe to cut their own parts. It really is just "a starting point"; it's a way to get a few quality parts into their hands and allow them to get going on some simple projects. Once they have the package, they will be directed to the SEMROC website for additional components. Think of this package as an appetizer before dinner; it's just enough to whet the appetite, and not enough to spoil it.Craig,

Your post helped crystalize my take on these "designer's special" type boxes. I started out as a BAR by building three kits and resurrecting three others from the attic. The Estes Designer's Special was helpful both in rehabbing the attic birds as well as letting me explore my own scratch and cloning ideas. No doubt this box was truly helpful. And I gladly paid the outrageous price at the B&M hobby store.

But once I got going, I pretty much moved beyond the Designer's Special. I could get plenty of balsa sheets from lots of stores. I picked up a stash of tubes and rings from TT and a stash of cones and rings from BMS. Cutting my own parachutes from many plastic bags was easy enough. (Glide floss makes great MR suspension lines :)

The point was that, once I got going, my bulk purchases tended to be more specialized. So I agree with you that these type things are mainly starting points. After that, it's hard for me to see much market for a "super duper gigantic deluxe designer's special". I don't see one as a starting point - it's too big - and I think most builders will be more specialized when they begin supplementing their stash beyond their first designer's special. (Plus, it's obvious that getting agreement on what goes into the super-duper box is about impossible :)

I'd say, after the basic designer's special type package with a sampling of everything, that the next best things would be ring packs, nosecone packs, body tube packs, etc. I think builders will see these as less wasteful and hehce more desirable.

Doug

[foose4string]

That was sort of my take on it too, Doug. I do like the idea of an assortment, but if it ends up costing more than a Designers Special, then I probably won't buy it. I don't want to pay 100 or even 50 dollars for a bunch of stuff I may or may not end up using. Parachutes were a good example. I got a whole pile of plastic chutes set asside from various kits now that I have learned how to use a sewing machine. Circle cutters are a good investment, and with a little patience and a free priority mailing box, centering rings are never a problem. I love laser cut parts as much as the next guy, believe me, but if I can fabricate it myself then why pay the premium? The lathe, vacuum or resin forming, is where most people's skills fall short, not to mention the expensive tooling for the task.

In short, builder's assortment pack is a great idea. But, I would keep it simple, as to try and keep the cost down. For me, an assorted tube pack is more desireable, pack of cones, etc. But then, I may be a bit more frugal then the average Joe, I dunno.

[CPMcGraw]

Craig,

Your post helped crystalize my take on these "designer's special" type boxes...once I got going, my bulk purchases tended to be more specialized. So I agree with you that these type things are mainly starting points. After that, it's hard for me to see much market for a "super duper gigantic deluxe designer's special"...I'd say, after the basic designer's special type package with a sampling of everything, that the next best things would be ring packs, nosecone packs, body tube packs, etc...

I might agree with the idea of "packs", as long as they contain genuinely useful components and not deteriorate into what Estes calls parts packs. What they have is like the original Chicken McNuggets: "They contain parts, and parts is parts". Still, I would like to see a "Super Box", something like a store might buy to start their pegboard inventory. I wouldn't mind spending $100 for a really complete box of goodies to fill my personal bins...

Maybe a combination of both ideas would be good: A small, appetizer-type parts box with a sampling of the most-used goodies; and a large, comprehensive "Store Sales Starter" with bags of parts, like rings by the dozen, tubes in six- or 10-packs, etc.

[Tau Zero]

I also prefer the larger 34" tubes, rather than 18" tubes.There are times I'd like about them that long, too. I guess I got spoiled with my one-time shipment from Totally Tubular. :rolleyes: :o


Getting rid of the spirals is a good thing, too! Who likes filling spirals. Can't we just get rid of them?Y'know, that's probably my *only* gripe with *any* Semroc product. I got some ST-5's with a *really* deep groove, which is why I took to sanding the tubes down even before hitting them with primer.

Hey Carl, is there any way you can order the ST-5's and ST-7's *without* the grooves? Or is that the best Euclid can do for the price you're paying them? Just wondering. ;) :D


Cheers, as always,

[CPMcGraw]

There are times I'd like about them that long, too. I guess I got spoiled with my one-time shipment from Totally Tubular. :rolleyes: :o


Y'know, that's probably my *only* gripe with *any* Semroc product. I got some ST-5's with a *really* deep groove, which is why I took to sanding the tubes down even before hitting them with primer.

Hey Carl, is there any way you can order the ST-5's and ST-7's *without* the grooves? Or is that the best Euclid can do for the price you're paying them? Just wondering. ;) :D


Cheers, as always,

Euclid isn't the only paper tube company. A few years ago, I got a brochure from another manufacturer -- Paramount Paper, I think -- that offered explicitly a line of white-outer-layer tubes with an "invisible" seam. It was actually a raised seam instead of a depressed seam; with a spray of primer and a base sanding, any trace of the seam was supposed to disappear. The raised edges supposedly caught and held the primer and the sandpaper "did the rest".

When I contacted them about the tubes, however, they acted like Sgt. Shultz: "I know nuthink! I see nuthink!" Today, I see no mention of them having anything like these tubes...

[CQBArms]

Maybe come out with the full standing fin jig/fixture. I mentioned this on the other forum but I will mention it here as well. Semroc seems to be awesome when it comes to improving good ideas, this was an excellent idea but I think it could be done better.

[CPMcGraw]

Maybe come out with the full standing fin jig/fixture. I mentioned this on the other forum but I will mention it here as well. Semroc seems to be awesome when it comes to improving good ideas, this was an excellent idea but I think it could be done better.

Agreed, but with better control than the Estes design. I'd like to see one with sliders and holders adjusted via thumbscrews instead of simply by friction. I never got mine "polished out" enough to work smoothly; there was always one plate that "grabbed" and caused more trouble than it was worth.

[CQBArms]

Exactly...or maybe like this but a lot less "involved"

http://www.bmicad.com/ebay/2.jpg

Agreed, but with better control than the Estes design. I'd like to see one with sliders and holders adjusted via thumbscrews instead of simply by friction. I never got mine "polished out" enough to work smoothly; there was always one plate that "grabbed" and caused more trouble than it was worth.

[CPMcGraw]

Exactly...or maybe like this but a lot less "involved"

http://www.bmicad.com/ebay/2.jpg

I actually was thinking of aluminum instead of plastic. You're using paper clamps, which probably work just as good; but I still like the idea of the thumbscrew adjustment, meaning I can set the pressure instead of taking all-or-nothing.

Nice looking jig!

[John Brohm]

I actually was thinking of aluminum instead of plastic. You're using paper clamps, which probably work just as good; but I still like the idea of the thumbscrew adjustment, meaning I can set the pressure instead of taking all-or-nothing.

Nice looking jig!

I've never liked the Estes Fin Alignment jig (even though they seem to be much sought after on eBay!) because, like Craig, I've found them finicky and somewhat imprecise; and being vertical, I don't like the potential for glue runs and sags. For a number of years, I've been using the tried & true matte board method. I've been picking up 8"x10" and 11"x14" matte boards at Michael's (in their framing department - you can usually get leftovers on the cheap). I've made up a family of templates (eg: BT-60/3 fin/3/32"; BT-60/4 fin/1/8"; etc, etc) that I use to hold the rocket and fins in a horizontal position (this by itself is not a new idea).

I layout the template as precisely as I can with compass and straight edge; I cut out all three (or four) fins, and then chamfer the points where the fin cutouts interface with the body tube (this allows the template to slide over the assembly without interfering with any glue alongside the fin joint). It's a method that's worked very well over the years and usually provides me with very precisely aligned, equally spaced fins. Since I like to surface my fins with tissue and dope before I glue them to the airframe, I find that the fin slots in the template have to be just a slight tad over-size so that the template will slide on without any binding.

I said all of that to say this: it would seem to me that Carl could generate an extremely accurate and comparatively inexpensive family of fin alignment templates with his laser cutter; with a bit of ingenuity, these could be setup on a horizontal bed with sliders, making the whole fin alignment process very fast and accurate; being horizontal makes it much easier to manage the glue (of whatever type one chooses to use). This setup allows the modeler to tailor his alignment jig to his liking (more or less sophistication), while keeping the whole thing inexepensive.

I'll offer up a couple of photos of my usual setup once I manage to get home to my shop.

[dwmzmm]

Carl,

When I saw this ad, my first thought was the goodies shown on the right was a SEMROC
version of the "Designer's Special." Heck, you may want to gather up all those parts shown,
throw them in a box and sell it as such. I know I could find plenty of uses in building my own
designs! How about it?

[James Pierson]

More Parts Carl, Please.

I would like to see PNC :eek: from Semroc. Yep, thats right PNC from Semroc, at least two in every size from ST-5 to ST-16. The big reason WHY, is that some of my freaky designs are only flight stable if I add alot of nose wieght and this can only be done by using the PNC's and stuff them with clay. I don't believe I can get that many WL-7 on for enough wieght.

I would also like a little design variety as well using some hollow Transitions. Some of my designs lately have used the BMS Boattail in Rocksim. This boattail is great for a more retro rocket look. The main reason WHY is that you should never attach fins to a paper transition and solid transitions can only be used above the recovery device if they are solid.

What about a Semroc tube marking guide. Well at least have a small aluminum or brass angle stock. Be for warned about your door jams gentlemen, they are not all pertectly straight :D . Wasn't Me! :D Just a little carpenter joke.

What I really need access to buy is a 3/16" x 48" Maxi-Rod for those design that just won't take to a diet well.

Thanks,

James Pierson
NAR#77907

[Carl@Semroc]

Carl,

When I saw this ad, my first thought was the goodies shown on the right was a SEMROC
version of the "Designer's Special." Heck, you may want to gather up all those parts shown,
throw them in a box and sell it as such. I know I could find plenty of uses in building my own
designs! How about it?Did not think of that! We just gathered up some "blems" that were laying around and "posed" them.

The lack of larger printed chutes and manuals have kept us from doing the "specials."

One special I always wanted was a set of all the body tube sizes in very short (2-3") lengths. I have access to that now. :D When I am building a rocket, I use a short piece of tube to fit the nose cone, then sand it, fill it, and paint it. THEN I finsih the actual body tube. This keeps all the sanding and layers of filler coat off the final tube. The short piece is then thrown away. I used to think that everyone did that.

[Tau Zero]

I said all of that to say this: it would seem to me that Carl could generate an extremely accurate and comparatively inexpensive family of fin alignment templates with his laser cutterYeah, he's, uh (cough) workin' on it. :rolleyes: ;) (See photo below.)


I find that the fin slots in the template have to be just a slight tad over-size so that the template will slide on without any binding.I was thinking just today that I need to go down to the tool store and pick up some Dial Calipers to determine what the tolerance should be, since the prototype guides below fit *real* (i.e., "too") snugly. :eek:

We need to cut some "triangles" to allow room for the fillets, :o so the fin guide doesn't get glued to the rocket. :mad:


Cheers,

[CPMcGraw]

What about a Semroc tube marking guide. Well at least have a small aluminum or brass angle stock. Be for warned about your door jams gentlemen, they are not all pertectly straight :D . Wasn't Me! :D Just a little carpenter joke.

The house I live in was built in stages, in different decades, and I think they used a rattlesnake for a chalk line...

As for the marking guide, I'd like to see one as well.

What I really need access to buy is a 3/16" x 48" Maxi-Rod for those design that just won't take to a diet well.

I just picked one of these up at Home Depot. You have to be careful, though, as not all of them are straight, either. Employees and customers don't always appreciate the model rocket flyer's need for a solid 48" of steel rod with NO KINKS.

[CPMcGraw]

Did not think of that! We just gathered up some "blems" that were laying around and "posed" them.

The lack of larger printed chutes and manuals have kept us from doing the "specials."

One special I always wanted was a set of all the body tube sizes in very short (2-3") lengths. I have access to that now. :D When I am building a rocket, I use a short piece of tube to fit the nose cone, then sand it, fill it, and paint it. THEN I finsih the actual body tube. This keeps all the sanding and layers of filler coat off the final tube. The short piece is then thrown away. I used to think that everyone did that.

Call it a Motor Tube Assortment, with "lots of additional uses"...

[James Pierson]

:D That guy using a rattlesnake for a chalkline "isn't the sharpest tool in the shed" now is he. LOL

I going to have to use that one at work Craig, that a good one.

For fin allignment, I have printed out the Centuri fin guide, set it on the floor and aline the BT on it with fin glued but not dry, look down from about and adjust the fins as necessary. Use the Force Luke, or your carpenter eye :D .

James Pierson
NAR# 77907

[CPMcGraw]

...I said all of that to say this: it would seem to me that Carl could generate an extremely accurate and comparatively inexpensive family of fin alignment templates with his laser cutter...

I made it a habit with the BARCLONE PDF plans to draw a fin guide like the one Jay has in his photo. (In fact, I think that's one I drew up for him on that project... :D ) I have found these simple cardstock holders to be just about as accurate, although I wished my own had been a bit thicker (and stiffer) at times. Carl's 0.07" cardstock would make ideal disposable guides which could be included in every kit at a nominal premium.

[Carl@Semroc]

More Parts Carl, Please.

I would like to see PNC :eek: from Semroc. We have checked into molds for nose cones. The best price I could find was $5K per nose cone! When I mentioned that to Bill Stine, he said I could get those in China for about $800. I mumbled that it did not look like we would be doing nose cones. I refuse to deal with China. I think I am too old to start trying to get along with them now.
/rant

We have done some work with resin cones using roto-casting. They work well, but are very labor-intensive. We are working on a resin cast nose cone similar to the PNC-50K, but it is not a high priority.


I would also like a little design variety as well using some hollow Transitions. We have done the BTC-55Z and are working on the BTC-70HZ that are hollow balsa.

What about a Semroc tube marking guide. Well at least have a small aluminum or brass angle stock. We do have a plastic angle we use with Scout groups, but it is not online. We are thinking of providing fin marking rings like Estes used to provide on some kits.

What I really need access to buy is a 3/16" x 48" Maxi-Rod for those design that just won't take to a diet well.When we do launch equipment, that will be added. The SLS series really needs that.

[Carl@Semroc]

I was thinking just today that I need to go down to the tool store and pick up some Dial Calipers to determine what the tolerance should be, since the prototype guides below fit *real* (i.e., "too") snugly. :eek: The tolerance for 3/32" balsa is +/- .010". If the guide is cut for the .103" "thick" balsa, the slots are too wide for the .083" balsa.

OR select a tighter range just for this kit.

We need to cut some "triangles" to allow room for the fillets, :o so the fin guide doesn't get glued to the rocket. :mad: Thought about that after I shipped them!

[James Pierson]

Thanks for the info Carl. And I agree with Made in the USA.

We have checked into molds for nose cones. The best price I could find was $5K per nose cone! When I mentioned that to Bill Stine, he said I could get those in China for about $800. I mumbled that it did not look like we would be doing nose cones. I refuse to deal with China. I think I am too old to start trying to get along with them now.
/rant


Maybe what we need is a heavier washer wieght that is dishes out that will still work with an eye screw. I have developed a way of hollowing out the BNC to install clay without messing up the coulper part of the cone, but it is not for beginner rocketeer's :( .

Thanks, JP

James Pierson
NAR# 77907

[CQBArms]

Or you could make them out of plastic or basswood and include them in that deluxe kit (the fin fixture/jig/guide things).
:)

I think that Semroc has it right, MADE in the USA and balsa nose cones.
The balsa cones set up nicer, are very "fixable", I just think they are "better" overall.
I deal with Russia, China, and India on certain parts for my work. If I could get away with not doing it, I would. But not many places that can stamp out a AK-74 parts set for replacement for so cheap and on the original machines with the original technical package.




I made it a habit with the BARCLONE PDF plans to draw a fin guide like the one Jay has in his photo. (In fact, I think that's one I drew up for him on that project... :D ) I have found these simple cardstock holders to be just about as accurate, although I wished my own had been a bit thicker (and stiffer) at times. Carl's 0.07" cardstock would make ideal disposable guides which could be included in every kit at a nominal premium.

[CPMcGraw]

We have checked into molds for nose cones. The best price I could find was $5K per nose cone! When I mentioned that to Bill Stine, he said I could get those in China for about $800. I mumbled that it did not look like we would be doing nose cones. I refuse to deal with China. I think I am too old to start trying to get along with them now...

The other thing I thought about, concerning plastic items, is the time-to-market delay. In the time it takes for one plastic tooling to be created, tested, revised, tested again, put into production, shipped, and finally received in the warehouse / packaging room, that Krellvenator could have produced multiple batches of the same cone and the kits could have been on the dealer shelves. The quicker turn-around time is worth any premium a balsa cone might cost, if there actually is any.

I'm not personally in favor of an injection-molded cone at this time. We've seen some applications already on this forum -- the Tau Tau is a good example -- of where a hollow, blow-molded plastic cone might be usable; and if SEMROC did venture into plastic that is what I might suggest. But I think the balsa components give these kits a feel that plastic takes away. I'd just as soon not see plastic used right now. Estes and Quest are in that camp. Their QC is in dire need of attention, and off-shore tooling is just one issue. Let's just "not go there"...

[Tau Zero]

I made it a habit with the BARCLONE PDF plans to draw a fin guide like the one Jay has in his photo. (In fact, I think that's one I drew up for him on that project...Oh, *so* close, Craig, but *no* cigar! :eek: :rolleyes: ;) :o

For the rest of you, this was Craig's original fin guide:

http://forums.rocketshoppe.com/showpost.php?p=10818&postcount=124


And here it is in operation:

http://forums.rocketshoppe.com/attachment.php?attachmentid=3383


I have found these simple cardstock holders to be just about as accurate, although I wished my own had been a bit thicker (and stiffer) at times. Carl's 0.07" cardstock would make ideal disposable guides which could be included in every kit at a nominal premium.Does that translate to 6-ply? I think these are 2-ply. Right, Carl?


Cheers,

[Tau Zero]

We need to cut some "triangles" to allow room for the fillets, :o so the fin guide doesn't get glued to the rocket. :mad:Thought about that after I shipped them!Yeah, well, *I* didn't think of it until I "tried them on for size" with a Tau Zero prototype. :o


The tolerance for 3/32" balsa is +/- .010". If the guide is cut for the .103" "thick" balsa, the slots are too wide for the .083" balsa. OR select a tighter range just for this kit.I'll have to get back to you on that.


Cheers,

[dwmzmm]

Did not think of that! We just gathered up some "blems" that were laying around and "posed" them.

The lack of larger printed chutes and manuals have kept us from doing the "specials."

One special I always wanted was a set of all the body tube sizes in very short (2-3") lengths. I have access to that now. :D When I am building a rocket, I use a short piece of tube to fit the nose cone, then sand it, fill it, and paint it. THEN I finsih the actual body tube. This keeps all the sanding and layers of filler coat off the final tube. The short piece is then thrown away. I used to think that everyone did that.

In the past, a lot of the parts that came with the Estes original Designer's Special (which had
stayed with me since the 1970's) also came in handy when I needed to make quick repairs/
rebuilds of my NAR contest "rated" models (especially the boost/rocket gliders and, on my
most recent "overnight" build, an 18 mm helicopter duration model -- the Gassaway styled
design). Speaking of which is why I need another "Designer's Special" as most all of the parts I had have been used up :(

[Eagle3]

...

We do have a plastic angle we use with Scout groups, but it is not online. We are thinking of providing fin marking rings like Estes used to provide on some kits.


I have small scraps of popular tube sizes already pre-marked for 3 and 4 fins. I socket the tube onto the body tube I need marked and use my angle stock to extend the pre-marked lines. Zip zip zip... done!

[John Brohm]

The tolerance for 3/32" balsa is +/- .010". If the guide is cut for the .103" "thick" balsa, the slots are too wide for the .083" balsa.

OR select a tighter range just for this kit.

Thought about that after I shipped them!

When I lay out my templates, I try to cut the slot width as precisely as possible, for just this reason. The tolerance on the balsa, plus the fact that I like to tissue the fins, means the slot width will vary slightly from project to project anyway. So making the templates out of matte board gives me something that I can sand to fit the width of the particular fins I'm using (also, the thickness of the matte board makes for a very sturdy template which makes for a better support). When the template gets too loose, I just make another one. Another reason to keep them cheap!

And as has already been pointed out, it's highly advisable to chamfer the slot points to make room for glue fillets (!).

[A Fish Named Wallyum]

I have small scraps of popular tube sizes already pre-marked for 3 and 4 fins. I socket the tube onto the body tube I need marked and use my angle stock to extend the pre-marked lines. Zip zip zip... done!

Excellent idea! It never occurred to me to do that, but I use scrap tubing for everything else. :eek:

[Eagle3]

Excellent idea! It never occurred to me to do that, but I use scrap tubing for everything else. :eek:

You could also use pieces that have been damaged or scavenge a R.I.P. bird. :)

[A Fish Named Wallyum]

You could also use pieces that have been damaged or scavenge a R.I.P. bird. :)

Pieces that have been damaged? That's my whole fleet! :rolleyes:

[rocket_james]

Exactly...or maybe like this but a lot less "involved"

http://www.bmicad.com/ebay/2.jpg
Now, that's a fin jig! Nice!

The problem with fin jigs is that they don't work well with exotic designs - think Estes Interceptor, Orion Starfighter or Torellian Invader just to name a few. I think separate cardboard jigs that are made specific to a kit are better. These could be included in the kit or offered separately. Alternatively, they could be printed on the instructions and the modeler could cut them out and glue them onto card stock.
James

[rocket_james]

...it would seem to me that Carl could generate an extremely accurate and comparatively inexpensive family of fin alignment templates with his laser cutter; with a bit of ingenuity, these could be setup on a horizontal bed with sliders, making the whole fin alignment process very fast and accurate; being horizontal makes it much easier to manage the glue (of whatever type one chooses to use). This setup allows the modeler to tailor his alignment jig to his liking (more or less sophistication), while keeping the whole thing inexepensive.
I totally agree! :D
James

[rocket_james]

Excellent idea! It never occurred to me to do that, but I use scrap tubing for everything else. :eek:
Yep! I have standard tube marking guides for two, three and four fins that are printed onto paper. Less storage space and it saves me a little time when building a kit - I don't have to cut out the provided marking guide. When one wears out, I just cut out another from that rather than searching through previously built kits for the leftovers. I have the same thing for the paper shock cord mounts. I am probably one of the few that prefer the paper shock cord mounts, only because I like to be able to inspect the attachment before launching. I do use Kevlar for the portion of the shock cord that stays inside the body tube, then elastic attached to that. I make a knot in the Kevlar right at the point of exit and cover with a thick glob of yellow glue to minimize abrasion to the tube. I also wick in CA into the top 1/4" section of the tube to also minimize abrasion.
James

[rocket_james]

Maybe what we need is a heavier washer wieght that is dishes out that will still work with an eye screw. I have developed a way of hollowing out the BNC to install clay without messing up the coulper part of the cone, but it is not for beginner rocketeer's
Try using all thread and a nut rather than an eye screw. Epoxy the all thread into the nose cone like you would a screw eye. Then you can add fender washers to put on however much weight you need, loop the shock cord end over the all thread and then tighten the nut over everything. Use another loop in your shock cord to attach the parachute.
James

[rocket_james]

I think that Semroc has it right, MADE in the USA and balsa nose cones.
The balsa cones set up nicer, are very "fixable", I just think they are "better" overall.
Don't get me wrong, I love balsa cones. They're what I grew up with, and I can put a finish on one that will make folks think it's plastic. That takes time, though. The problem with plastic cones is the seam lines, much harder to finish than with balsa. One manufacturer has a nose cone that is extremely smooth with only a small dimple near the base where the plastic was injected. Only minimal finishing was required to produce excellent results! I'm in favor of that kind of plastic cone. Also, plastic allows a lot more design options. That said, though, for environmental and the Made in the USA aspects, I'm all for balsa!
James

[Ltvscout]

They're what I grew up with, and I can put a finish on That said, though, for environmental and the Made in the USA aspects, I'm all for balsa!
Heh, be careful. The tree huggers will start crying about all the balsa trees being cut down!

[rocket_james]

Heh, be careful. The tree huggers will start crying about all the balsa trees being cut down!
Acck! That's true! :D
Seriously, I do worry about our rain forests. Any manufacturer should check out their vendors to be sure they are friendly to the environment. At least, as much as that is possible.
James

[CPMcGraw]

Heh, be careful. The tree huggers will start crying about all the balsa trees being cut down!

Actually, I doubt it: In the places where balsa trees grow, they're almost considered a weed...

They act as "nurse trees" in forests, protecting younger trees from the elements until they become mature.

Just a bit of interesting, if otherwise useless, trivia...

See this URL: http://jimsrc.com/other_info.html

[sandman]

Environmentally balsa makes more sense than plastic. It's similar to the plastic Christmas tree vs. real Christmas tree argument.

Balsa is renewable and highly biodegradable...and plastic is well...plastic.

Also the "Made in America" aspect seems tro me to be a better option. Most plastic cones if not already probably soon will be made else where and balsa cones are all made here.

Then again I am partial to balsa.

After all...I am "SANDMAN"! :D

[Mark+3]

Carl, how about 8" and 10" preprinted parachutes.

[dwmzmm]

Carl, how about 8" and 10" preprinted parachutes.

FSI's plastic chutes were preprinted so you could choose a variety of sizes (not sure, but
I think the smallest was 7"; will have to check what I have in my storage when I can get
around to it...). It's more convenient than having preprinted chutes just for one size only.

[Mark+3]

FSI's plastic chutes were preprinted so you could choose a variety of sizes (not sure, but
I think the smallest was 7"; will have to check what I have in my storage when I can get
around to it...). It's more convenient than having preprinted chutes just for one size only.

That sounds great. I normally use chutes in the 7-12" range.

[Carl@Semroc]

Preliminary Engine List (Small) (http://www.semroc.com/documents/engine%20table%20-%2010-18mm.asp)

This is for purpose of critique and discussion of planned engines. It does not include the 15mm or anything larger than 18mm in this pass.

[Ltvscout]

Preliminary Engine List (Small) (http://www.semroc.com/documents/engine%20table%20-%2010-18mm.asp)

This is for purpose of critique and discussion of planned engines. It does not include the 15mm or anything larger than 18mm in this pass.
Carl,

I get a Login Required message when I hit that URL.

[Mark+3]

Carl,

I get a Login Required message when I hit that URL.

Me too.

[CPMcGraw]

Me three...

[Carl@Semroc]

Carl,

I get a Login Required message when I hit that URL.You have to login to your account on Semroc site first. All the SVDT members can get to protected pages.

[Mark+3]

Preliminary Engine List (Small) (http://www.semroc.com/documents/engine%20table%20-%2010-18mm.asp)

This is for purpose of critique and discussion of planned engines. It does not include the 15mm or anything larger than 18mm in this pass.

Wow, what a selection. Great variety of delays, including almost all as boosters.
3/4A shorty and tiny; full B 13mm micro are nice surprises.
T sizes with delays staggered from Estes to allow selection in one second intervals. :)

[CQBArms]

Is there a link that lists all the hidden pages?

[Carl@Semroc]

Is there a link that lists all the hidden pages?There will be. Right now, this is the first as an experiment to see how it works.

[CPMcGraw]

Preliminary Engine List (Small) (http://www.semroc.com/documents/engine%20table%20-%2010-18mm.asp)

This is for purpose of critique and discussion of planned engines. It does not include the 15mm or anything larger than 18mm in this pass.

DECAP-0s are "deployment-only" pyro charges, yes?

I'll see what I can do with the ENG files for RockSim. You wouldn't know if all of these have a RASP file somewhere in an archive, would you? Or even just some hand-drawn thrust plots?

[Carl@Semroc]

DECAP-0s are "deployment-only" pyro charges, yes?

That's right. They have a clay nozzle to work with standard igniters and three different charges. This will be to meet the need of TARC teams that can't handle BP.

I'll see what I can do with the ENG files for RockSim. You wouldn't know if all of these have a RASP file somewhere in an archive, would you? Or even just some hand-drawn thrust plots?I don't have this yet. I have been working on it in spare time.

[Pyro Pro]

The page loaded fine for me; it looks like a very nice selection of motors. (And a full "D" in there too :) ).

[CQBArms]

As I am a complete dope when it comes to this, could you explain the full implications of the DECAP stuff?

The way I have pictured it, there's an engine with just a thrust component then you can add these DECAP's on top, some have delays and some are just pyro, which would work with dual deploy?

So I envision it like a modular BP system?
Choose your thrust, then choose your delay & ejection charge?

Also weren't there pictures of the engines or am I going crazy?

[Carl@Semroc]

As I am a complete dope when it comes to this, could you explain the full implications of the DECAP stuff?

The way I have pictured it, there's an engine with just a thrust component then you can add these DECAP's on top, some have delays and some are just pyro, which would work with dual deploy?

So I envision it like a modular BP system?
Choose your thrust, then choose your delay & ejection charge?

Also weren't there pictures of the engines or am I going crazy?There are multiple applications here. They are all called DECAP's but their functions are different.

1. Standard delay, ejection charge, and clay cap - glues into a booster engine to convert it to a single stage or upper stage engine. Used to get more precise delays and be able to mix and match propellants and delays on the field. DECAP -1 through DECAP-9

2. Same as above but with higher volume ejection charges for rockets with large parachute sections and no stuffer tubes to cut down volume. DECAP-1X through DECAP-9X

3. Plug only. This is simply for converting a booster engine to a plugged engine so it can be used in clusters without ejecting itself. No delay or ejection charge. DECAP-P

4. Plug with smoke only. This DECAP has a 10-13 second smoke delay with no ejection charge. It is similar to #3 in use, but does do a little extra work by making the cluster rocket more visible. DECAP-S

5. Ejection charge only. This one is NOT glued into a booster engine. It is a standalone package with a simulated "nozzle" for an igniter and an ejection charge and clay cap. There are four versions differing in amount of ejection charge. DECAP-0 through DECAP-XXX

Then there is the smaller version "T" for the 13mm booster engines.

There may be some additional applications or types not listed here.

[Carl@Semroc]

Also weren't there pictures of the engines or am I going crazy?
Engine family portrait (http://www.semroc.com/documents/engine%20family%20portrait.jpg)

[James Pierson]

I can't find a preliminary engine list when I log in at Semroc. Just my order numbers show up :( . I promise to learn the secret handshake or whatever Carl. However, I refuse to ride that goat, I swore I would never do that again :D , JP

James Pierson
NAR# 77907

[CPMcGraw]

I can't find a preliminary engine list when I log in at Semroc. Just my order numbers show up :( . I promise to learn the secret handshake or whatever Carl. However, I refuse to ride that goat, I swore I would never do that again :D , JP

James Pierson
NAR# 77907

Log in, as if you were checking your account, then Copy-n-Paste the URL into the "address" bar.

It's there...

[CPMcGraw]

There are multiple applications here. They are all called DECAP's but their functions are different...(snipped for brevity)...

Carl,

On your motor list, are you including the DECAP motor bases?

[James Pierson]

Thanks Craig, I got the list. :)

James Pierson
NAR# 77907

[Carl@Semroc]

Carl,

On your motor list, are you including the DECAP motor bases?They are standard booster engines if I understand your question.

[Gus]

5. Ejection charge only. This one is NOT glued into a booster engine. It is a standalone package with a simulated "nozzle" for an igniter and an ejection charge and clay cap. There are four versions differing in amount of ejection charge. DECAP-0 through DECAP-XXX

These will sell big. Tremendous idea.

What type of igniter are you envisioning for these?

The list is amazing, Carl. I particularly like the 13mm Bs.

[Carl@Semroc]

These will sell big. Tremendous idea.

What type of igniter are you envisioning for these?

The list is amazing, Carl. I particularly like the 13mm Bs.Standard Estes, Quest, or Semroc igniters.

13mm B is preliminary. Centuri had trouble, early Estes did not, MPC had it, but I don't know their track record.

[Eagle3]

Standard Estes, Quest, or Semroc igniters.

13mm B is preliminary. Centuri had trouble, early Estes did not, MPC had it, but I don't know their track record.

I burned quite a few MPC 13mm B's along with my NAR team mate. As I've mentioned before, awesome motors and never had a problem with one.

[Carl@Semroc]

I burned quite a few MPC 13mm B's along with my NAR team mate. As I've mentioned before, awesome motors and never had a problem with one.That is good to know. I think I have a few around here somewhere. I will probably fire a few on the test stand when I get time.

I think Centuri was trying to pack too much in each step since several tubes are bulged.

[dwmzmm]

I burned quite a few MPC 13mm B's along with my NAR team mate. As I've mentioned before, awesome motors and never had a problem with one.

I think I still have a "live" MPC B (13 mm)motor in my collection of vintage motors dating back to the early 1970's...

[CPMcGraw]

They are standard booster engines if I understand your question.

That tells me what I need to know. Every "standard" booster (-0) motor becomes a DECAP with the addition of the special DECAP package. I was looking for a designation to separate these out, but they're just simple booster motors. OK. Brain is now in gear. Thanks.

With that said, can we get a C10-0 and a D10-0 added in 18x70 mm, ones that we can add a DECAP to? I suspect these are PBs, right? My Star Ranger design purrs contentedly on these, according to RockSim... :D

[Carl@Semroc]

With that said, can we get a C10-0 and a D10-0 added in 18x70 mm, ones that we can add a DECAP to? I suspect these are PBs, right? My Star Ranger design purrs contentedly on these, according to RockSim... :DIt is not so easy to get a C10 in 18mm. BP burns at about .8" sec at 100 psi, so... a port burner would burn out in about .35 seconds so you would get a B14, 3/4C19, C28, D56, etc. Never had luck with a C28 and never even tried a D56. To get a C10 in an 18mm package would require a much lower burn rate propellant.

Gary Rosenfield calls these the "sweet spots" for given propellants in given diameters with given geometries. Good term. That is why for BP you see average thrust for 18mm around 6N, for 13mm around 3N, and 24mm around 12N.

Estes uses a larger throat with lower pressures and lower Isp to get the B4. That is a safe modification. A smaller throat with higher pressure (and burn rate) could get higher thrusts in an end burning configuration, but with an unacceptable amount of CATO's.

[Ltvscout]

You have to login to your account on Semroc site first. All the SVDT members can get to protected pages.
I was logged in already. I logged out and then back in and it then came up. Very impressive list of motors there, Carl! I like!

[CPMcGraw]

It is not so easy to get a C10 in 18mm. BP burns at about .8" sec at 100 psi, so... a port burner would burn out in about .35 seconds so you would get a B14, 3/4C19, C28, D56, etc. Never had luck with a C28 and never even tried a D56. To get a C10 in an 18mm package would require a much lower burn rate propellant...

A longer casing would not contribute to greater pressure in this application, right? It would only "sustain" a given rate. You really need volume around the middle (diameter) to generate the needed pressure, and this is why we see BP C11s and D12s in 24mm rather than 18mm? It gets down to how much propellant is burning at a given instant of time rather than how much propellant gets burned over a(n extended) length of time.

That 3/4C19 interests me, then...:D

[Eagle3]

That is good to know. I think I have a few around here somewhere. I will probably fire a few on the test stand when I get time.

I think Centuri was trying to pack too much in each step since several tubes are bulged.

I never got my hands on any Centuri B's. I still have a ton of Centuri mini A's, but I think the previous owner temp cycled them. Everyone has gone off like an M-80. :( I still have a couple of packs of MPC B's, but *sniff* I don't have the heart to open and burn em.

The Semroc motor lineup looks great and I see so many vacant holes being filled. That D5 will be a great motor! B4... B7.... B14... man, I can't wait!!!

[Carl@Semroc]

A longer casing would not contribute to greater pressure in this application, right? It would only "sustain" a given rate. You really need volume around the middle (diameter) to generate the needed pressure, and this is why we see BP C11s and D12s in 24mm rather than 18mm? It gets down to how much propellant is burning at a given instant of time rather than how much propellant gets burned over a(n extended) length of time.That is correct.

That 3/4C19 interests me, then...:DLarge rockets for school yards!

[foose4string]

Yep, the D-5 will sell like hotcakes. I saw the A8, B6, but why no C6 on the list?

EDIT: Sorry, I see it now, didn't see it earlier when I looked.

[CPMcGraw]

...Large rockets for school yards!

Depends...

The C10-3 was what I was looking at, and it took the Star Ranger up to 290'. The D10-3 took it to 470'. It got the model off the pad quickly -- 20" for the C10 versus 35" for a C11.

How does the 3/4C19 compare to a C10? Or even to a D10? The "19" tells me this is a port burner, and the formulation would burn rather quickly, producing a lot of internal pressure. I don't have any graph to compare with, so I'm just guessing it could lift a model of comparable size (2.9 oz) to flight velocity in about 14" instead of 20". The down side would be the short duration of the sustainer burn following the spike.

Star Ranger is a "big" model at 40.2" long... :D

[Carl@Semroc]

Depends...

The C10-3 was what I was looking at, and it took the Star Ranger up to 290'. The D10-3 took it to 470'. It got the model off the pad quickly -- 20" for the C10 versus 35" for a C11.

How does the 3/4C19 compare to a C10? Or even to a D10? The "19" tells me this is a port burner, and the formulation would burn rather quickly, producing a lot of internal pressure. I don't have any graph to compare with, so I'm just guessing it could lift a model of comparable size (2.9 oz) to flight velocity in about 14" instead of 20". The down side would be the short duration of the sustainer burn following the spike.

Star Ranger is a "big" model at 40.2" long... :DIt is just a .35sec spike, no sustainer.

[CPMcGraw]

It is just a .35sec spike, no sustainer.

Is the curve like this...? (See attached RSE file)

[Chas Russell]

I have logged out and in several times on two computers and copied and pasted the URL and all I get is three pages of engine related parts. Guess I missed the meeting about the secret handshake.

Plus I can't open .rse files...

I'll go back to fighting with Best Buy over the piece o' stuff TV stand they mucked up.

Chas

[CPMcGraw]

I have logged out and in several times on two computers and copied and pasted the URL and all I get is three pages of engine related parts. Guess I missed the meeting about the secret handshake.

Plus I can't open .rse files...

I'll go back to fighting with Best Buy over the piece o' stuff TV stand they mucked up.

Chas

RSE -- RockSim Engine file...

RSE files are opened by RockSim's Engine Editor program for editing and adding new motors to the various vendor's files. This program also reads ENG files from RASP; you can open a file from one type and save to the other.

RockSim reads RSE files when it cranks up; that's where it gets all of the engine data for simulations.

[Chas Russell]

Thanks Craig. I have an early version of RockSim, but have not installed it. More of a "seat of the pants" modeler.

Chas

[ghrocketman]

Carl,
For some reason even when logged into my Semroc account, I cannot access the "protected" areas of the Semroc website.
Where should these docs be showing up on the screen ?
I get "log in required" whenever I click on the link you provided.

[Ltvscout]

Carl,
For some reason even when logged into my Semroc account, I cannot access the "protected" areas of the Semroc website.
Where should these docs be showing up on the screen ?
I get "log in required" whenever I click on the link you provided.
Log out of your Semroc account and then back in again. If that doesn't do it try clearing your cookies.

[ghrocketman]

I have logged in, logged out, logged back in, and cleared cookies and still cannot access
"Preliminary Engine List (Small)" http://www.semroc.com/documents/engine%20table%20-%2010-18mm.asp

What "base" page on the Semroc site does this show on, or is it not a "clickable" link ?

[Ltvscout]

I have logged in, logged out, logged back in, and cleared cookies and still cannot access
"Preliminary Engine List (Small)" http://www.semroc.com/documents/engine%20table%20-%2010-18mm.asp

What "base" page on the Semroc site does this show on, or is it not a "clickable" link ?
There is no page on the Semroc site that shows the hidden links.

If it's any consolation, I can't access that page now either. :confused:

[A Fish Named Wallyum]

There is no page on the Semroc site that shows the hidden links.

If it's any consolation, I can't access that page now either. :confused:

Nope. Me either. :confused:

[Bob H]

Carl,
For some reason even when logged into my Semroc account, I cannot access the "protected" areas of the Semroc website.
Where should these docs be showing up on the screen ?
I get "log in required" whenever I click on the link you provided.
Try this: right click the link and chose "copy shortcut".
Sign on to the Semroc site and paste the link into the address bar and that should work.

At least it worked for me.

[ghrocketman]

Bob H,
Thanks for the tip....that actually worked and I was able to access the page.

[CPMcGraw]

Thanks Craig. I have an early version of RockSim, but have not installed it. More of a "seat of the pants" modeler.

Chas

If it's earlier than Version 7, you really need to update to Version 8. Some of the files created in the earlier versions are no longer supported in the later versions, and needless to say, the later files are not readable in the older versions. Apogee should be getting Version 9 ready for release about now; seems like it's been about a year since Version 8 came out...

[Carl@Semroc]

It does not work! :eek:Try it now. There should be a link on the home page if you are logged in.

[CPMcGraw]

I'm working on turning that chart on the SEMROC website into a full RSE file. Be patient, because I'm trying to fabricate working curves for the burn patterns which actually fit the data. Some of these may initially be way out of whack, and if so I apologize. Carl will have to look at the curves and see which ones need correcting, and how much.

I hope to have these ready for release here by next Tuesday...

[Ltvscout]

Try it now. There should be a link on the home page if you are logged in.
Heh, I love it. A pocket protector icon! If you don't see it right away, log out and back in again. It'll be on the top right above the Classic Kits icon.

[Chas Russell]

I also enjoyed the pocket protector icon. Having started back in the late '60s, it just seems so right for this effort. I was able to access the files and it looks like if even a fraction of these motors come to fruition in the near future that there will be sleepless nights in Penrose.
Any chance of a "tiny" A3-6 instead the -5?

Chas