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Wondering "Why Kevlar?"

I wholeheartedly agree. I use this on just about everything.

My only concern with the Quest method is the string elastic. It strikes me as being more prone to zippering during a high speed deployment.

While I admit to never having used the Quest elastic (I have a stash now, pssst - anybody want some?) it seems to me that flat elastic will spread the load out over a wider section of the opening thus being less prone to zippering.

In all my Quest kits, I have always replaced the string elastic with flat, so I've never tried the string elastic , but I have gotten zippers in the past (on other, non-Quest rockets) and I don't want any more of them.

BTW, I love the blog thing. It's a great way for Quest to win the hearts and minds.

Doug Anybody know whatever happened to Andy at PML?

Reply to
Doug Sams
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I haven't used steel leader in model rockets since before we first teamed up. I know I DQed an event and lost a place at NARAM-19 because one broke.

Composites are particularly nasty on small metal leaders.

The NCR "Gorilla" mounts use heavy enough cable that this doesn't seem to be a problem.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Reply to
Bob Kaplow

I'd make this a very low priority. Flight testing might be better. There are too many variables to choose, etc. As a start, I guess you could start with a steel leader, and then pick a Kevlar cord of the same mass at equal or greater installed length. Of course you should also include the mass of the anchor, if that differs.

In the end I suspect that both will be satisfactory and out live the life of any model. In the end it will come down to personal preference, or perhaps price. Certainly it is easier to transfer a steel leader from a dead model to a new one than a Kevlar leader, if one wanted to reuse parts. The steel leader is certainly convenient, but the Kevlar is more versatile with customizable lengths. It seems pointless to test a factor that does not matter to user selection. Suppose the Steel leader is good for 10,000 cycles, and the Kevlar is good for 9,000 cycles, while what matters is how close the modeler lives to a fishing supply store?

Alan

Reply to
Alan Jones

The only reason I would put it on the list is that I have a "which glue holds up to motor heat the best" test I'm going to run. I figured if I was running tension tests in my environmental chamber (furnace), I could do something else along side.

Agreed.

Doc

Reply to
Doc

The trick with these is to make the loops in the end small or it will grab the recovery system and prevent deployment. Had that happen to my NCR Interceptor G once, ouch! It lived to fly again, though.

Reply to
Tim Burger

Oh yes, Into The Wind on the Boulder Mall. Spent many a long hour (and many $$) there! I believe that they've stopped selling Kevlar. I have the still have the remains of the last two rolls purchased there - they sold it for kite line, but I bought it for shock cords and 'chute shrouds. The kite fliers all switched to Spectra and the demand for it went away. The stunt kiters all seemed to have found new hobbies, anyway.

Reply to
Tim Burger

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