Semroc Saturn 1B w/24MM

[Race58]

I'm getting reading to build my Semroc Sat 1B. I was thinking rather than use the 3 motor cluster or the 1 "D" motor that I would try a 24MM reload. Does anybody know if this has been done before or that it would work at all?

[tbzep]

I'm getting reading to build my Semroc Sat 1B. I was thinking rather than use the 3 motor cluster or the 1 "D" motor that I would try a 24MM reload. Does anybody know if this has been done before or that it would work at all?

It'll work just fine and dandy. You could also build it with a BT-70 core to house removable mounts. You could go with the quad 18mm mount or the 24mm mount according to your mood or motor supply. With the BT-70, you could even rig it up to fly on three 24mm motors. :)

[ghrocketman]

First of all the Semroc S1B is not a 3 angine cluster, it is a 4x18mm engine cluster, with optional single 24mm instead.
Yes you can use the 24mm RMS in this kit as the D15-4T is one of the suggested 24mm engines.
This engine is ONLY available as a 24mm RMS reload from Aerotech (it does not exist in single-use form).
This engine is about equivalent to a 4-engine cluster of Estes B6-4's albeit with lower peak thrust.

I am going to use either this engine or the Aerotech 24mm RMS E28T (About equal to 4 estes C6-5's) for my first flight.
I'm leaning toward the D15-4T.

[tonypv]

I've flown mine with a E15-4 and a F24-4, both great flights.
Here's a pic of the F24 flight.

[tbzep]

I've flown mine with a E15-4 and a F24-4, both great flights.
Here's a pic of the F24 flight.

That's a cool looking shot!

[Race58]

I knew that!! :confused: As I have said before I suffer from CRS and I was living in the past with my Sat V which had a 3 cluster. For some reason I was under the impression that the Aerotech type motors had a different mount but now I see that they are the same size as an Estes "D" which is the biggest we had back then.
Thanks for jolting my brain back online. :D

Would you suggest then the 4 engine cluster or the Aerotech reloads for a more realistic liftoff/flight??
thanks againFirst of all the Semroc S1B is not a 3 angine cluster, it is a 4x18mm engine cluster, with optional single 24mm instead.
Yes you can use the 24mm RMS in this kit as the D15-4T is one of the suggested 24mm engines.
This engine is ONLY available as a 24mm RMS reload from Aerotech (it does not exist in single-use form).
This engine is about equivalent to a 4-engine cluster of Estes B6-4's albeit with lower peak thrust.

I am going to use either this engine or the Aerotech 24mm RMS E28T (About equal to 4 estes C6-5's) for my first flight.
I'm leaning toward the D15-4T.

[Race58]

Now that sounds like the answer to my problem. :D Where would one get a BT-70 conversion kit like that??It'll work just fine and dandy. You could also build it with a BT-70 core to house removable mounts. You could go with the quad 18mm mount or the 24mm mount according to your mood or motor supply. With the BT-70, you could even rig it up to fly on three 24mm motors. :)

[Race58]

That is a GREAT shot. Which motor did you use on that flight?I've flown mine with a E15-4 and a F24-4, both great flights.
Here's a pic of the F24 flight.

[cas2047]

Not sure about the interchangeable mount but I built mine with the 18mm Quad setup theflights are always impressive. It looks really cool going up with four flame trails and lots of smoke.

Here is a picture just after ignition.

[barone]

Not sure about the interchangeable mount but I built mine with the 18mm Quad setup theflights are always impressive. It looks really cool going up with four flame trails and lots of smoke.

Here is a picture just after ignition.
Next to a scale rest room for the astronauts.... :eek:

[cas2047]

Next to a scale rest room for the astronauts.... :eek:

You know I never looked at it that way before but from now on when I look at that picture it's going to make me laugh. :D

[barone]

Isn't it amazing how people notice other things in a photo that aren't the subject of the photo? Bill is really good at that.... :rolleyes:

[cas2047]

Isn't it amazing how people notice other things in a photo that aren't the subject of the photo? Bill is really good at that.... :rolleyes:

It sure is, and it also reminds me of how poorly I setup many of my shots, that is when I even get the shot off in the first place - lol!

This one however will now always give me a chuckle because my eyes will drift to that lower right hand corner and the "scale rest room for the astronauts". ;)

[foose4string]

Now that sounds like the answer to my problem. :D Where would one get a BT-70 conversion kit like that??


No "kit" exists as far as I know. A few weeks ago I asked Carl @ Semroc if a kit was available. He said that he started one some time ago, but thought better of it for stability reasons. He was worried about adding weight to the rear of an already marginally stable design. He said they might be able to do the rings, but he'd have to double check to see if he had the file. He said they would do custom rings no problem if a drawing was submitted. I thought it wouldn't hurt to ask though, say if they had the BT70 section, 2 BT70 couplers, and extra hook or two, the 4 x 18mm rings, 1 x 24mm rings, and a washer or two, all bagged together for say 10 bucks or so.

I'm just going to fabricate most of the stuff myself, except the tube and couplers. I love my circle cutter, it's the best 6 bucks I ever spent in rocketry. although nothing beats the ol' Semroc laser cutter! ;)

[K.M.Knox]

The only thing missing is the launch complex... Great looking rockets guys and nice launch pics. For shear neatness I would lean to the 4x18mm cluster, anyone can throw a single engine in and get that to ignite :D But to get all 4 to go everytime? that could make for some interesting flights... :p

[tbzep]

No "kit" exists as far as I know. A few weeks ago I asked Carl @ Semroc if a kit was available. He said that he started one some time ago, but thought better of it for stability reasons. He was worried about adding weight to the rear of an already marginally stable design. He said they might be able to do the rings, but he'd have to double check to see if he had the file. He said they would do custom rings no problem if a drawing was submitted. I thought it wouldn't hurt to ask though, say if they had the BT70 section, 2 BT70 couplers, and extra hook or two, the 4 x 18mm rings, 1 x 24mm rings, and a washer or two, all bagged together for say 10 bucks or so.

I'm just going to fabricate most of the stuff myself, except the tube and couplers. I love my circle cutter, it's the best 6 bucks I ever spent in rocketry. although nothing beats the ol' Semroc laser cutter! ;)

A "kit" like you mention is nice, along with some removable nose weights and simple instructions on how and when to add them. They could be added to the capsule and held with the screw eye.

[moonzero2]

I'm just going to fabricate most of the stuff myself, except the tube and couplers. I love my circle cutter, it's the best 6 bucks I ever spent in rocketry. although nothing beats the ol' Semroc laser cutter! ;)

I been wanting to get a good circle cutter,... what one do you have and where did you get it?

[Race58]

That would have been my ?? also. :) I been wanting to get a good circle cutter,... what one do you have and where did you get it?

[tbzep]

I have a Hobbico from Tower Hobbies. Link to Tower Page. (http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXHEA0&P=ML)

http://www.hobbico.com/tools/hcar0230-main-lg.jpg

[barone]

I have a Hobbico from Tower Hobbies. Link to Tower Page. (http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXHEA0&P=ML)

http://www2.gpmd.com/image/h/hcar0230.jpg
Now that looks REALLY handy....I'm going to have to get one.

[cas2047]

I have a Hobbico from Tower Hobbies.

OK one more thing on my must buy list. I just got a 10 off on 50 or more order from Tower so I'll have to find some way to spend the other 44 bucks. I'm sure I can find a couple of other things I need there. :D

How long do the blades last? I'm wondering if it would just make sense to order an extra set right from the get go.

[tbzep]

I've only used it a couple of times. I keep forgetting I have it.

What I have found extremely useful is the small vise I got in the same order this spring. My son and I use it so much that I think I'm going to have to get a second one because he's always using it.

Link to vise (http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXHFG0&P=ML)

http://www.hobbico.com/tools/hcar0680-main-2.jpg

[cas2047]

I've only used it a couple of times. I keep forgetting I have it.

What I have found extremely useful is the small vise I got in the same order this spring. My son and I use it so much that I think I'm going to have to get a second one because he's always using it.



Doh - just added that to my wish list also! :) I better not ask any more questions. :rolleyes:

[foose4string]

I have a Hobbico from Tower Hobbies. Link to Tower Page. (http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXHEA0&P=ML)

http://www.hobbico.com/tools/hcar0230-main-lg.jpg

Yep, that's the one! Although, mine is red and I bought it from a LHS. I've had mine about a year now, made a few dozen ring, and haven't changed the blade yet. I'm surprised at how long the blade has lasted. I think the key is not to force down on the blade too hard, but to make several light passes around. I'm not using matte board, but rather using the thin corrugated priority mail boxes(hey, their free :o ). They seem to be doing the trick very nicely.

[foose4string]

A "kit" like you mention is nice, along with some removable nose weights and simple instructions on how and when to add them. They could be added to the capsule and held with the screw eye.


The washers that I mentioned were in reference to the removable weights, installed just like you described.

[UCBadger]

After about 35 years "retired" from model rocketry, I received a 1B kit for my 51st birthday. (Does this make me a BAR?) I have not started it for several reasons, the most important being that I have not decided if I go one engine or four. If I go one 24 mm engine, I know that the Estes D13-3 is recommended as is the D15-4 reloadable. I have seen mention of E15-4, E28T, and F24-4 on this thread.

My question is (I guess) are all the engines reloads except the D13-3 and are the higher power engines (E&F) reloads which fit the same engine as the D15-4? (Do they all work in the same engine holder?) And a follow up question is what would you recommend if I may not have access to a "higher power" launch system capable of reliable ignition of a cluster system.

Thanks,

Curtis

[MKP]

Congratulations, you are a BAR! :)

The Aerotech E15 is a single use engine, the closest reload to it is an E18. The D15, E28 and F24 are reloads in the 24mm casing. My personal favorite in the 24mm reloads is the F12( nice long burn).

All of the Aerotech 24mm engines, both single use and reload, use Copperhead igniters, which work best with a 12V launch system, as do clusters, so you best off either build a 12V launch or buying one, the cheapo Estes controller won't cut it.

Hope this helps some,

Matt

[tbzep]

After about 35 years "retired" from model rocketry, I received a 1B kit for my 51st birthday. (Does this make me a BAR?) I have not started it for several reasons, the most important being that I have not decided if I go one engine or four. If I go one 24 mm engine, I know that the Estes D13-3 is recommended as is the D15-4 reloadable. I have seen mention of E15-4, E28T, and F24-4 on this thread.

My question is (I guess) are all the engines reloads except the D13-3 and are the higher power engines (E&F) reloads which fit the same engine as the D15-4? (Do they all work in the same engine holder?) And a follow up question is what would you recommend if I may not have access to a "higher power" launch system capable of reliable ignition of a cluster system.

Thanks,

Curtis

The Estes D12-3 is the same size as the single use E15-4 and the reloadable 24mm casing for D's and E's. You can go with a single 24mm mount and be able to use several different motors.

If this wasn't your first build in so many years, I'd recommend to modify it for a removable motor mount so that you could swap in whatever type of motor combination you like. I'd still recommend it if you can get some good pictures or maybe even find a club member with one already modified so you can see what needs to be done.

As for clustering, the simplest way is to use a plain jane launch system with 12v battery, whether it is a car, motorcycle, lawnmower, makes no difference. You can get fancy with relays, but it really isn't needed until you start working at longer distances from the pad.

[Doug Sams]

What I have found extremely useful is the small vise I got in the same order this spring.

http://www.hobbico.com/tools/hcar0680-main-2.jpgI like the swivel section. That part would make a very nice launch pad head :)

Doug

.

[tbzep]

I like the swivel section. That part would make a very nice launch pad head :)

Doug

.

It sure would. :)

[conleyt]

Congratulations, you are a BAR! :)

The Aerotech E15 is a single use engine, the closest reload to it is an E18. The D15, E28 and F24 are reloads in the 24mm casing. My personal favorite in the 24mm reloads is the F12( nice long burn).

All of the Aerotech 24mm engines, both single use and reload, use Copperhead igniters, which work best with a 12V launch system, as do clusters, so you best off either build a 12V launch or buying one, the cheapo Estes controller won't cut it.

Hope this helps some,

Matt

You can get E15s and E30s for cheap from here: http://www.valuerockets.com

And, Aerotech now has FirstFire Jr. igniters for their 24mm and 18mm motors.

Tom C.

[UCBadger]

Congratulations, you are a BAR! :)

The Aerotech E15 is a single use engine, the closest reload to it is an E18. The D15, E28 and F24 are reloads in the 24mm casing. My personal favorite in the 24mm reloads is the F12( nice long burn).

All of the Aerotech 24mm engines, both single use and reload, use Copperhead igniters, which work best with a 12V launch system, as do clusters, so you best off either build a 12V launch or buying one, the cheapo Estes controller won't cut it.

Hope this helps some,

Matt

Thanks, Matt.

How difficult are the reloads? I guess I am inclined to stick with the single use engines unless I find out that the Aerotech reloads are not terribly difficult.

Just to make sure I am clear, if I build the model with the "estes D engine" mount, I can use the Estes D12-3, or the Aerotech E15-4W (even though it is not listed as recommended by Semroc) single use motors or use the Areotech RMS-24/40 motor system with D15-4T or E18-4W or E28-4T or F12-3J(?) or F24-4W reload kits. (With the understanding that only the D15-4T is recommended by Semroc)?

(Of course if I need a 12V launch system, might just as well go cluster, right?)

[tbzep]

Thanks, Matt.

How difficult are the reloads? I guess I am inclined to stick with the single use engines unless I find out that the Aerotech reloads are not terribly difficult.

Just to make sure I am clear, if I build the model with the "estes D engine" mount, I can use the Estes D12-3, or the Aerotech E15-4W (even though it is not listed as recommended by Semroc) single use motors or use the Areotech RMS-24/40 motor system with D15-4T or E18-4W or E28-4T or F12-3J(?) or F24-4W reload kits. (With the understanding that only the D15-4T is recommended by Semroc)?

(Of course if I need a 12V launch system, might just as well go cluster, right?)

That is correct.

[snuggles]

Use an E motor mount(with hook). It's longer than a standard D12 mount.
You'll have to use the orange spacer with the Aerotech motors.
Also, the spring clip needs to have a small bit cut off at the top end.
Otherwise the 24mm motor casing will not hook properly.
Try to fit everything in the MMT before you glue it.
I had a V2 with an 24mm mount and found that I couldn't get an Aerotech casing in it.
Hope this helps
Mark T

[MKP]

I don't find reloads to be very difficult, just follow the directions and you'll be fine. Just go easy on the grease, that seems to be the most common mistake. They're really not that complected once you see how they work.

The 24/40 reload case will fit in any rocket with a 24mm motor mount, either the D or the longer E, you just need a spacer in the E motor mount. The only problem you'll run in to is that front of the motor hook will often snag the delay closure of the reload case (the very front end). This is easily resolved when building a new rocket, simply file the hook's tang down or clip it off until it clears. On a built rocket, you can file it down with a rat-tail file, or my preferred method, a Dremel with a flexible shaft attachment( much faster.) That's the only problem I've run into.

Again, I hope this helps...

Matt

[UCBadger]

Matt, that was very useful, thanks. I don't have the motor casing at this time, any guess to how much of the top of the motor hook needs to come off?

[MKP]

I usually clip it off to about half its original size, or when you install it of the motor mount tube, you can no longer see it protruding inside the thrust ring's inner diameter. I hope that's understandable. :chuckle:

[UCBadger]

Yes, it is. Thanks

(Now tell me where do the rats go?)

[MKP]

The rats stay home on launch day. They chew balsa and body tubes something terrible. :)

[luke strawwalker]

I have a Hobbico from Tower Hobbies. Link to Tower Page. (http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXHEA0&P=ML)

http://www.hobbico.com/tools/hcar0230-main-lg.jpg

I got one exactly like that at Michael's for $6. VERY VERY handy toy! OL JR :)

[Jeff Walther]

And a follow up question is what would you recommend if I may not have access to a "higher power" launch system capable of reliable ignition of a cluster system.

We spent a while discussing launch systems with some ummph! in this thread: Launch System Power (http://forums.rocketshoppe.com/showthread.php?t=4101)

Mostly we discussed power sources. But once you have a power source the rest is simple. There are wiring diagrams of launch controllers in the older catalogs (scans available at ninfinger.org), try 1969 Estes, e.g.. The wiring diagram is helpful both for building your own from scratch, or for modifying an existing system to use the higher capacity power source.

Of course, if you still have an old Estes launch controller from 35 years ago, chances are it has two battery clips which you can easily connect to any of the convenient and cheap 12V sources which are available today. You know, the red one, with one cable going to the launch pad with microclips on the ends, and one cable trailing out behind to a car or lantern battery with big alligator clips on it.

[UCBadger]

Thanks for pointing me to the power thread, Jeff.
While my question really was "one engine or four?" I take one answer to it is "get a good launch system!" :D

Yes, I once had the Estes launch system which hooked to an automobile battery, but I did not take it with me when I left home and it is long gone.

[luke strawwalker]

Thanks for pointing me to the power thread, Jeff.
While my question really was "one engine or four?" I take one answer to it is "get a good launch system!" :D

Yes, I once had the Estes launch system which hooked to an automobile battery, but I did not take it with me when I left home and it is long gone.

It's not very hard to make the Estes controllers into something worth having... I've done a pair of them myself. The newer ones with the glued together casings would be a bit harder, but should still be doable with some ingenuity and forethought.

If you want to know more, just ask, and I can post some pictures... OL JR :)

[UCBadger]

After several years of putting off the decision, I have started my Saturn IB, opting for the 4 motor configuration (mainly because I now have a Saturn V in my "to build" collection which will be a single motor configuration). I know that Semroc list only C6-5 as rocommended engines. Older Estes catalogues (http://www.ninfinger.org/rockets/nostalgia/70est024.html) list A8-3 and B6-4 as possible engines. Does anyone have experience using B engines in the Semroc model?

[mwtoelle]

I would think that it would get to about 300 feet on a B6 cluster. You will need to weigh your finished model before deciding which motors to use. YMMV.