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Like an idiot

Hi,

Like an idiot I went out and got some kevlar thread 10,000 dernier (whatever that is) Looks strong but not nice as looking as the

300lb. test one can get from Apogee. Supposed to be 400lb test. I haven't used it as shock cord and I should have posted it before I bought it. The link is here:
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What does anyone think? Look like it might be satisfactory material. Well I will find out as I used some with a motor mount mounting in a G size Super Big Bertha. I may make a secondary shock cord mount with Epoxy and a kevlar loop on the body tube a' la LOC (like in my Aura) and attach a secondary parachute. If all goes well, I could disconnect the secondary shock/parachute at the loop and just use the single main shock unit that is connected to the motor mount. Everything is modified with plywood rings and an extra body tube for a payload bay. It is just apogee deploy with ejection charge and I can use an adapter for 24mm engines.

Kurt Savegnago

Reply to
Kurt
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You're not an idiot. Be of good cheer.

But also consider why my Kevlar costs more than buying spools of it through The Thread Exchange; I specced it out for model rocket use. So does Quest.

I don't have any problem with hunting for a bargain; I love to do it too. And I've often gotten caught with bargains that turned out not to be useful for what I had in mind (usually from Harbor Freight, it seems). I guess it's one way to learn.

400 lb isn't a bad number for model rocket use. Test it and see if it accepts glue; a drop of Elmer's will keep the knots from coming untied if the Kevlar isn't coated. If it is coated, swage the loops. The coated Kevlar will come untied no matter how tight the knot is, given enough time.
Reply to
pratthobbies

Hi,

It is three thick strand but not shiney like the apogee product. I think it will be O.K. but Will us a backup on the Super Big B modified.

Kurt Savegnago

Reply to
Kurt

Awhile back, I purchased some "sight unseen". It was thinner than I expected. I simply use three pieces, hand-braided together, to give it some "heft".

Reply to
Greg Heilers

Tried it in a Richter Wrecker and it worked O.K. Used two 36inch surplus chutes from Aerocon. One tangled but got the ship back fine. I think the booster tube was crinkled by the thrust of the D engines as the descent rate was reasonably slow. Will cut the tube and epoxy a coupler. The tube feels a little thin past the engine mount and may have suffered from the hibachi effect and burned.

Kurt

Reply to
Kurt

The thread is OK If you loop it around a few times to make a 2-3 inch loop, and use it to connect a nylon strap tubing shock chord to your rocket body. I use epoxy and it is bullet proof.

Reply to
Greg Cisko

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