If their phenolic formula hasn't changed, I think that is the worst
choice. I have never seen a LOC kit have an ejection charge blow the
side out of the airframe. I have however had that happen in an Endeavor.
Giant Leap is a good choice for kits...
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I've never seen this happen once in the last 6 years, in any material,
and I for one use large ejection charges. 2g of BP in 300mm of 54mm
tube for instance. I have one particular airframe I've done this at
least 30 times in with no damage whatsoever. That's with shear pins
You think? If I were going to buy fibreglass tube, the last thing I'd
buy is Giant Leap. It might be fine for a few flights but as soon as
you ding the end of the tube, or put a hole through it to access your
altimeter, cracks start to propagate along the laminations because
it's spiral wound, not convolute wound. We did one flight on a fairly
easy-going M motor (a M1400 skidmark), and had a pretty easy landing,
and the tube was trashed. Just twisting it in difference directions
at each end made it come apart in your hands. Absolutely awful stuff.
MARS Flight Crew http://www.mars.org.uk /
I like the quantum tubes and they do hold up pretty good to general abuse.
I've only had 2 failures with quantum tube but under those circumstances
I doubt if even carbon fiber could've survived. One was a G80 cato in
my PML IO and the other happened last July when a H180 decided to eject
right after burnout in my Calistro.
The zipper on the Calistro is most impressive; went all the way down to
the MM and stripped the chute but the rocket still came down in one piece :)
I know we're getting way off the OP's topic, but I'm not a fan of QT.
I've built one rocket out of it and that was enough. I found it to be
affected too much by the ambient temperature and in the summer all the
phenolic couplers are too loose, conversely, in winter they're all too
bob [at] bobarnott [dot] com http://www.bobarnott.com /
Bob did say "coupler" not "piston". :-)
Be that as it may, I'm surprised PML doesn't supply QT couplers (and
pistons). Dissimilar materials in a close-tolerance fit is a terrible idea.
Is the nose cone fit in QT also subject to temperature? (I have no
experience with QT.)
(replace "spambait" with "merlinus" to respond directly to me)
I love the stuff almost as much as fw fiberglass. Just to give the
whiners a little something to talk about - I also like pistons - after
I fit them correctly by sanding and I glass the inside of them.
For me they are both relatively cheap and easy to get. I don't know
what the story is where you are.
I'm not sure which one is shit. I own both, they have both been
steppend on and have survived. I can't say that for tubes that don't
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