PGerringer
Ruler of Heck
- Joined
- Jul 12, 2001
- Messages
- 1,778
- Reaction score
- 5
Does it expand like a bungee cord or is it stiff like a standard rope?
Tubular Kevlar question
- Thread starter PGerringer
- Start date
Help Support The Rocketry Forum:
A
Austin
Tubular Kevlar is indeed just that, tubular in shape, so it does expand. However some people have been having problems with Kevlar strap in general as it does not flex and has broken on more than one occasion. You may wish to stay with the more flexible Nylon and use a Kevlar sheath on the lower end for ejection protection. It's less stress on the model because it does expand better.
Tubular kevlar has a bit of stretch, just like tubular nylon and most rope, about 1%, but nothing like bungie. It's usefulness lies in it's strength.
To overcome it's lack of stretchyness you use more of it than you would bungie cord, a lot more. For example, I used 10 feet of 3/8" TK in my Big Daddy, build mostly stock. It's pretty flame proof but I use a nomex pad to protect the chute.
To overcome it's lack of stretchyness you use more of it than you would bungie cord, a lot more. For example, I used 10 feet of 3/8" TK in my Big Daddy, build mostly stock. It's pretty flame proof but I use a nomex pad to protect the chute.
PGerringer
Ruler of Heck
- Joined
- Jul 12, 2001
- Messages
- 1,778
- Reaction score
- 5
Wow, I thought that was the point of the kevlar. Not to break on heat. Are you sure it was heat that snapped it and not the force? From all the above posts, it looks like Kevlar doesn't have much "snap" so if it is too short for deployment, I could see where it would be Kevlar or Rocket.
PGerringer
Ruler of Heck
- Joined
- Jul 12, 2001
- Messages
- 1,778
- Reaction score
- 5
Well, now that kinda changes things. I had in my mind that Kevlar would never be hurt by heat. And that is expensive stuff to be burnin'. Thanks for the info.
