Truth and Consequences

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Well-Known Member
Jan 25, 2009
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TRUTH: Rocksim will allow you to design rockets and assure stability.

CONSEQUENCES: Rocksim will make you want to build anything you design immediately.

TRUTH: Mailing tubes are a cheap alternative to normal LOC/PML tubing.

CONSEQUENCES: Every rocket you want to build will be based around said mailing tube, since your $8+ LOC 3.0" tubing is 'special'.

TRUTH: With a LOC/PML kit, you are assure a high quality product at a reasonable price.

OPPOSING TRUTH: If you completely scratch build something, you are assured that it is the ONLY one out there!

I could go on forever with these, but I need to get ready for school, so here's the design details.


2x 29mm
4 rear fins
3 forward fins
Inspired by a Shrox design and the BSD Thor

See attachment for the line drawing. More later at construction continues.

I have thousands of RockSim files and not as many rockets, so I am not so sure that "Rocksim will make you want to build anything you design immediately."

Bruce S. Levison, NAR #69055
I agree with jetra about mailing tubes. The ones with full telescoping inside tubes are my favs. And, I agree with teflon on rsim. I design many more 'what-ifs' than rockets I build. I also have multiple versions of many of the ones I ended up building. But thousands...I'm not there...yet.

OOPs...forgot something important...nice rocket ;)
(music)Cutting fin slots, cutting fin slots, cutting fin slots, JOY(/music)

/sarcasm mode off

The rings are cut with the 2x 29mm mount, will cut fins Wednesday, cutting fin slots tonight. It's TTWTTMMT (Thru The Wall To The Motor MounT) for the lower fins and dado-slot for the upper. It's interesting to see it come together. Will have pix tomorrow afternoon.

Alrighty...finslots and fins are cut, so here are the pics.

Looking in the tube with slots cut and one CR in to see what'll it look like...droool! :D

Here's an exterior pic of the slots. Notice the brown/white triangle. I'm calling that a dado-slot, since it's a slot, but it doesn't go all the way through.

I had a thought looking through this thread again. Instead of doing the dado-slot, I am going to cut the entire slot then do the old-LOC style fin-tab route and add a tab made out of balsa of basswood to the fin to ensure proper alignment.

Good call on that dado-slot. I tried that with horrible results - the thinned cardboard tube was exceptionally weak in that area, and the fins punched right through, despite being epoxied into position. In fact, I had better success with surface-mounting than I did with subsurface mounting. You'll be better off just going with the slots, then attaching some form of a backing to them from the inside, and epoxying everything in place.

Yeah. I'm not impressed with the way they turned out. If anything, they MIGHT have improved the bond, but my cutting job with the jigsaw was very even, so either the ends or just the middle would've fully contacted the tube.