I'm a BAR building mid-power. I remember from my younger days that the Estes kit elastic shock chords got brittle after a few flights and were subject to sending my descending rocket in two different directions. My LOC Aura kit has an elastic shock chord. Should I replace it with a Kevlar shock chord from the getgo? I wonder if it's more likely to zipper with Kevlar than with elastic?
TIA - Jacob
Elastic belongs in your underwear, not your rockets. ;-)
Should I replace it with a Kevlar shock chord
Tubular nylon is the way to go. Use at least 15 feet.
-- Drake "Doc" Damerau
Jacob,
DO NOT USE ELASTIC!!!! I did on a pre-production LOC A4/V2 3.9" and no offense to Barry but this was extremely lacking. 1st flight certified L1 second flight broke and nose cone bit the big one, came in Ballistic from about 1500 ft scared the heck out of us when nearly hit our vehicles. It had a lot of shot in nose and carried quite a load on impact. Now use only tubular nylon I got on ROL auctions a whole lot of it real cheap. About
15-20 foot should do nicely. Best of luck welcome back and keep 'em flying!Dale
I use a combination of kevlar and elastic. About half of the cord is kevlar, which is the part that is attached to the rocket. It's heat resistant so it won't burn through. Then I add a length of good quality "underwear" type elastic (at least 1/2" wide) to that. On larger rockets (4" diameter) I use 1" wide elastic.
Most folks these days skip the elastic altogether and just use a very long length of nylon or kevlar cord.
unless I'm using an anti-zipper design (see below) I generally use Kevlar to just past the body tube, then nylon tube from there
you could use all nylon, but then I'd recommend a Kevlar (Giant Leap) or Nomex (Rebel Rocketry) shock cord sheath at the base
some anti-zipper techniques on shown on InfoCentral at
Doug at Pratt Hobbies has a good selection of Kevlar in small sizes for MR
at
Ed at Giant Leap has both Kevlar and Nylon tubing
at
also see the Rebel rocketry site at
enjoy!
- iz
Jacob Dent> I'm a BAR building mid-power. I remember from my younger days that the Estes
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