Altaira Rocketry Friede build thread

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J Blatz

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Hello rocket friends.

So in an attempt to battle my sadness, anxiety, and chronic pain I am going to build a rocket. I know that seems like a backwards thing to but at the moment it seems better than nothing.

I picked up two Altaira Friede kits off of ebay from the company owner Matthew Johnson. This kit is 4" diameter, 20"long, and flies (not very high lol) on 12 X D12-3. It is modeled after an old sci-fi movie. It has THREE pounds of noseweight to make it stable which is of course an awful lot of noseweight. A large reason for this is the heavy motors....I may build one stock and the other with a 38mm MMT and less nose weight. An H242 is 280 grams, the 12 D12's are like 530 grams. Don't get me wrong, I dig the cluster, but the H242 would be thumpy too...or maybe ye olde H550 Super Thunder.

Ok, going to unbox this sucker.
 
One nice thing about a cluster of D12's is that you get a lot of red fire and smoke over a broad base, which is quite a sight to see. Using e-matches and poster-taking putty makes D12 clusters easier. Either way I'm glad you are documenting.
 
Ok, here's what's in the box. Parts are a bit crude. MMTS are BT-50 rather than 24MM MMT and are smashed into various states of out-of-round by the lead weights which were not secured other than being in bags. Note cool vacuum formed nosecone.

Also have all kinds of fin stock, aluminum duct tape for thermal insulation on the fins, 4 X 30" chutes, kevlar, decals, instructions, etc...
 

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So the first thing I wanted to address was making some replacement motor mount tubes since the ones that came with the kit were smashed and also wimpy thin wall stuff. So I cut 12 3" long motor mount tubes out of LOC 24MMT which has a thicker wall.

I'm so smart.

Except that tiny bit of extra wall thickness in the motor tubes pushes the airframe out of round. So that's a fail, esp given the huge amount of fin/AF joint area on this rocket . And I don't have any BT-50, plus I'm not convinced from looking at the fit that the airframe wouldn't get pushed out of round when motors are installed even using the thinner BT-50 motor tubes.

Here's a pic of the bulged out airframe...
 

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I think that the motor tubes for the N-1 were thin, also, but I used them and things worked out. I even put motor retaining hooks on them. Some of the other construction bothered me, but ended working for at least 2 flights so far without problem. I thought the chamber above the motor tubes looked small and weak, but it worked. I wondered about the N-1 having 6 D12's to eject the parachute, but thinking about it now a lot of force is probably needed to eject the heavy nose cone.
 
Jason, I have some extra Estes bt50 tubes laying around somewhere. If you still need mmt tubes you can have em. Lmk
 
So the first thing I wanted to address was making some replacement motor mount tubes since the ones that came with the kit were smashed and also wimpy thin wall stuff. So I cut 12 3" long motor mount tubes out of LOC 24MMT which has a thicker wall.

I'm so smart.

Except that tiny bit of extra wall thickness in the motor tubes pushes the airframe out of round. So that's a fail, esp given the huge amount of fin/AF joint area on this rocket . And I don't have any BT-50, plus I'm not convinced from looking at the fit that the airframe wouldn't get pushed out of round when motors are installed even using the thinner BT-50 motor tubes.

Here's a pic of the bulged out airframe...
Hey they fit,maybe tougtgen up air frame with some CA,but my question,why,12 D12s igniting, go with the H.
 
OK, to resume. Sorry for delay. So as mentioned earlier, the motor tube arrangement leaves a lot to be desired. I have another direction I think I'll go, but that's for a future post.

First I laid out all plywood and sanded w 320. Then I applied a single coat of some trash water based sealer I had layin around to the outer surfaces. No need to make it too pretty...this kit is not, you know, a beauty queen.

Let's talk about the fin construction. They are a four piece job, with two identical side pieces, a center piece which is slightly less tall, and a top cap piece. The root edges are 12", and the width about 1.5", and the plywood is not real straight. The instructions call for one to bevel the inside edges of the outside pieces, which I did. You can (maybe) see this is in the pic....
 

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The instructions call for gluing the two fin sides directly to the AF and then adding the center strut and the top cap. Looking at my warpy pieces, I made the executive level decision to build the fins up prior to attaching to the airframe in the hope that would make them straighter/less wonky.

To this end I made a jig with two pieces of 1"X4", real simple just screwed together to make a 90 degree jig. Then to build each fin I used junk CA and kicker to glue the center strut to the top cap (this was eyeballed, no jig used) . Once that was done, I attached the sides to the top cap using my jig, one side at a time.
 

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Ok, so it's been a minute.

As you can see previously I was unhappy with the original MMT sitch. So I decided to build this thing with a disposable motor "battery". Basically it is an assembly in which the front surface of the D12s are epoxied to a bulkhead plate which has holes drilled in it to allow the ejection charge gasses to pass through. This "battery" of motors mates up to fixed bulkhead plate with matching holes that is glued inside the airframe and is held in place by screws that pass through the top ring into t-nuts placed in the motor "battery" assembly.

The advantage is supposed to be that there can be no airframe flex due to the AF being pushed out of round when the motors are inserted. It also offers very positive motor retention.

To this end, I made three rings out of LOC 1/4 bulkhead plates that I ordered cut to fit airframe, not coupler. I laid out the D12s on one of the rings and marked their position. Then I eyeballed in the centers of each hole and also three anchor points as well as a reference point and marked this as well. One ring is to be glued in the airframe, the second to be built into a motor assembly, and the third to be asked as a pattern to build future motor assemblies good-lord-a-willin (i.e., if this thing doesn't munch playa on the first run).

After marking the first ring, I stacked them together and secured them with a big wood screw through the center and a self tapping screw through the reference hole. Then I drilled out the three holes on the outer perimeter that are to be used for tnuts/screws and put three screw through them into the backing 2"X6"to hold it all tight while the holes for ejection charge are drilled. Said holes are 5/8" and this was all done on a drill press after I removed the center wood screw since it would have been in the way of the 5/8" drill bit I used to make the big holes.

Pics show progression of ring fab.
 

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After making the rings it occurred to me that I have never seen a motor glued onto a centering ring before. So to test the premise and be sure it would work I took a small piece of plywood and drilled a 5/8" hole through it. Then I took a C11 and applied a bead of 5 min epoxy around the front end surface of the motor and glued it into place over the hole I drilled in the plywood.

Test went well and freaked dogs out, too.
 

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Yes. It is a completely different set up. I got a little twisted and maybe carried away after the initial issues with smashed tubes and then the too-darned-tight situation. This is better, I think.
 
Ok, now to build the motor mount battery assembly TM. First step was to push t-nuts into place with my vice and then trim them with the Dremel tool so they don't interfere with gluing the motors on flush.

I mixed up some 15 minute epoxy and applied it to front edge of the motors and glued them all into place, squaring them up at the end to make sure they are positioned squarely over the ejection holes.

Final pic shows completed assembly in place from the point of view of the top of the airframe. I used the motor mount assemble battery to push the top ring into place and then applied wood glue circumferentially to the junction where said ring meets the airframe. Then I removed the motor mount battery assemble and let the glue dry.

It turned out pretty good, I think.
 

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Hi Folks. The Rocket "Freide" was used in the movie "Frau Im Monde" It was also the 1st movie to use the "Countdown" and water for the cooling of the exhaust ala Cape Kennedy space Center. Currell.net has a cardstock model of it and also info on a flying version of it. I believe that it is a single engine version. Fritz Lang and Willy Ley build a flying model of it for the premier of the movie, but the Nazi's seized it from them before it could be flown. I hope this helps.
 
Since this kit became available, I've wondered why it was designed with a large cluster? 12 D motors is high power, seems like there would be less need for nose weight with maybe a 38mm mount for a 2-grain H. Does the BT length dictate that really short motors be used? In any case, it certainly is a neat looking rocket!
 
Since this kit became available, I've wondered why it was designed with a large cluster? 12 D motors is high power, seems like there would be less need for nose weight with maybe a 38mm mount for a 2-grain H. Does the BT length dictate that really short motors be used? In any case, it certainly is a neat looking rocket!

You make a good point. I get the idea that the designer is not really a traditional model rocketeer. This thing is definitely "done the hard way" and to build and fly it correctly is probably more difficult than most people's L2 certs. And yes, it is well into the high power range...for big boys (and girls) only.
 
More progression. I had to make a fin marking guide since the one that came with the kit stopped an inch shy of wrapping around the AF. Anyhoo, easy to do. Pics show marked tube from side, and then a view of the inverted airframe which has had the edge strengthened with CA. After this, I drilled the holes for the rail buttons since I think using a 1/4" X 4' rod as suggested is pure crazy with a 4+ lb 12 motor cluster.
 

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