New scratch build, now "Binary Effusion"

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Hint: in base 32, letters, as well as numbers, are used to represent the bits. So convert that decimal number into base 32 and see what happens...

Thats pretty good. After running the number through a converter, of course. Anything other than base 10 is out of my league.
 
Ha! You're probably right! I must have over 50 rockets, if you include LPR.

You've got some catching up to do... if you're counting quantity of rockets. I've got some catching up if we're limiting it to HPR.

What am I at now? 175? 180? I've lost count.

BTW, I Love the design! But it'll take a while before I even think of tackling something like that. I think I need to up my build to buy ratio... 7 to 1? 8?
 
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Not bad....

But even better still (because you know... its longer... which totally makes it wayyy more technical:p) try, 34843065842292238975058177077694941 converted to base 32
Now that's a nice one!
 
I drew alignment marks the full length of both motor tubes, to align with marks on the centering rings. The forward centering ring needs to be 3/4" from the ends of the tubes, so I used 1/4" and 1/2" spacers. I couldn't find any 3/4" spacers. The aft centering ring (at the top in the photo) isn't epoxied on yet, it's just to align the motor tubes while the epoxy sets on the forward centering ring.

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I covered the holes in the centering ring with tape, so I could fill them when I applied the epoxy fillets to the other side.

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I epoxied on some 3/16" plywood blocks for the tee nuts, then drilled them out with a 3/16" bit. I covered the tee nuts with epoxy so they can't push out.

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I'm using a transition for the tail cone. I was going to leave a 3/4" shoulder, but decided on a 1" shoulder instead. I wrapped a piece of tape around it, to act as a cutting guide, when I cut it with the bandsaw. I cut the small end flush. I got the fin and rail button lines drawn on, then couldn't resist a dry fit.

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Another jig. Sort of. I used a length of 1/4" aluminum rod to set the position of the inner tube. I wiped oil on the end just to make sure it didn't stick to the epoxy.

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Have you thought about your motor retention setup yet?

Yeah, I have an idea. I thought about Estes retainers, but the tubes are too close together. I could use Giant Leap slimline retainers, But they're expensive. I think I can use my usual 1/8" x 1/2" aluminum bar and make retainer clips. Once I get the motor mount and aft centering ring epoxied in, I'll start working on them.
 
Jim,how did you cut your centering rings?Did you do them at the same time?I never cut any rings that had duel motors.Hole saws mybe but the alinement would pose a problem for me.Great build so far,that's one huge motor mount.
 
Have you thought about your motor retention setup yet?

How about a threaded rod in-between the motor tubes, then using a nut and washer that cover the lip of the motor casings? I've used this several times on 3 motor clusters, don't know why it wouldn't work on a two motor cluster.
 
Jim,how did you cut your centering rings?Did you do them at the same time?I never cut any rings that had duel motors.Hole saws mybe but the alinement would pose a problem for me.Great build so far,that's one huge motor mount.

Hey Carl,

I pretty much used my usual techniques. I cut out the centering rings with a hole saw, and sized them on the lathe. But for the dual motor tubes, I printed out the centering ring template from Open Rocket to mark the centers of the two motor tube holes. I put the two rings together with screws and nuts before cutting the two holes, to ensure their alignment. Then I sized them with a sanding drum in the Dremel.

https://www.rocketryforum.com/showt...quot-Binary-Effusion-quot&p=693149#post693149

https://www.rocketryforum.com/showt...quot-Binary-Effusion-quot&p=693303#post693303
 
Wow. Don't know how I missed this. Really great looking project! If I may ask, what are the T nuts in the aft centering ring for?
 
How about a threaded rod in-between the motor tubes, then using a nut and washer that cover the lip of the motor casings? I've used this several times on 3 motor clusters, don't know why it wouldn't work on a two motor cluster.

That's actually one of the methods I considered. But I prefer something that holds from two sides. Call me paranoid.
 
Thanks,I'll have to try that on my next future duel motor build.
 
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