Pardon my ignorance

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Aug 1, 2004
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However what exactly is Rip-Stop Material. I'm using Mylar and am very happy with.. stilll learning.. I did a search i found plenty of info but none on the actually materal
Ripstop is a type of nylon used in parachutes. That's all I know about it.
Ripstop nylon is designed to resist ripping. Don't let that fool you. Once a rip forms, it will continue. You can tell a fabric is rip-stop when you see the square pattern formed when the thicker strands of nylon cross each other.
I think rip-stop nylon was originally developed for use in outdoor clothing and camping gear about 40 or 50 years ago

it was supposed to make tears more difficult to enlarge by having reinforcing threads (spaced like every 1/4 or 1/2 inch)
outer layers of some outdoor coats were made with this stuff, and some gear like sleeping bags were also designed with it
you can sometimes find it in bulk form in the stores that sell sewing supplies

nylon fabric (rip-stop or plain) is definitely a step up in quality and the finished 'chutes can look **very** nice, but you have to sew the edges or else the material will unravel
what it boils down to is: you have to have (or get access to) a sewing machine
you have to spend a couple hours sewing and assembling the 'chute
and you still have to protect it from the hot ejection gases or else the nylon will melt
it is a lot more work to make a nylon parachute but they are almost required for the heavy rockets

if you have been comfy with mylar, and if you are only flying low-power and mid-power stuff, then you will probably be fine to stick with it
if you have a relatively heavy rocket and you are not sure if the mylar will stand up to the loads, use a little more elastic shock cord to help reduce the strain
mylar is pretty nice stuff and you can still make your own 'chutes pretty easily----and it's cheap! nothing at all wrong with mylar, or the other sheet plastics
If your making your own Hemispheral type chutes, Rip-Stop reinforced nylon is almost a must. Several places on line carry a multitude of colors and different weight materials. Most use the lighter weight per sqare yard material for both flat and hemi parachutes, streamers and Kite coverings;) heres an old pic of some homemade Rip-Stop chutes.
I only use rip stop nylon. If you're lucky you can pick it up at a good fabric store. Right now I have like 10 colours!
Originally posted by Zericon
However what exactly is Rip-Stop Material. I'm using Mylar and am very happy with.. stilll learning.. I did a search i found plenty of info but none on the actually materal

Mylar is fine if you handle it right. It warps from heat so it needs good wadding protection. And it can stick together, so you can't pack it the night before. That latter reason the is the only real reason I mostly use nylon now. There are some very good contest mylar chutes. On the other hand, there's some real junk made from mylar, and mylar chutes that people make poorly themselves, and I think that's why some people don't like it.

Tomorrow I'm first-flying a really spiffy all chrome 50's sci-fi looking cluster bird, designed for the DESCON contest. I'm trusting it to an 18" chrome mylar Rockethead chute.

The answer to your question has to do with how the cloth is woven. Most weaves, once they start to tear, continue along the line of the thread parallel to the tear. Rip stop is woven so that the tear tries to take off on the perpendicular to the tear, and if it does, then THAT tries to take off perpendicular, etc. Some is good, some is not so good. Even the worst will tend to bring a bird down safely when the chute might otherwise shred, but the cheap stuff won't give you a second chance. Once it's torn, it'll get worse, just not in a straight line.