Saturday, October 3, 2009

Even more carbon fiber success

I was finally able to lay up two new 38 and 54mm minimum diameter designs with 2 wraps of 6 oz carbon fiber cloth and cure them in 1 hour with a nearly perfect finish. The key seems to be plugging in the curing oven right when you place the part and then unplugging at exactly 1 hr. I then let both tubes cool down in the oven for about 1/2 hr then pulled the Mylar™ film and release fabric off while they were still warm to the touch. Here are the finished tubes and I'm tacking the fins on with JB Weld Quick:
I have one batch of high-temp black epoxy left and I want to use it on both designs so all fins need to be tacked down and ready. Knowing that Derek Zoolander stands 5'6-1/2" tall I've built this comparison to my new designs for scale:
I really shouldn't even be talking about these designs because they're really-really, really-really, ridiculously good looking.


R2K said...

Those fins are tiny!!!!

G Frickin' Muneh said...

Yes they are! The RockSim stability equations indicate that the worst-case static margin for both design is ~1.25 (with the biggest motors). With small motors the static margin increases to 5-6. I think most fins are way too big at the cost of increased drag and risk of flutter and subsequent failure. Thanks for commenting.