Nowhere near the engineering head that you are. But I know that they use protective gear made with Kevlar specifically for high heat industrial situations so my guess is that it has a fairly high heat resistance .... but not sure if there is a difference between Kevlar string as opposed to how Kevlar is applied, in conjunction with other materials, when making high heat resistant protective equipment.

As long as you have fun. Just don't get empailed.

Life: No one gets out alive.

Kevlar is superb for rigid aerostats, but it's usually quite expensive. I'd tend to use it only for elements that are likely to suffer heat and/or impact damage, such as nose cones, fins and engine housings. I actually still use asbestos occasionally for my propulsion assembly linings and bulkheads, its cheap and superb at heat protection (but u arnt supposed to use it really; dust) but to answer ur question, the kevlar won't burn at the temps u'll be generating but u may get heat transmission through it if it's too thin. It can get a little brittle if exposed to prolonged HT, u won't have this problem.

Edited by - Tawakalna on 30-11-2003 14:03:50

Thanks guys! Heat resistant... just what I needed to hear.

@Indy- It is just plain ol kevlar, but in the form of thread. I shall have some fun with the excess I'm shure

@Taw- Expensive? 300+ yds for $12 and shipping. Not bad if you ask me. Could have gotten 1200 yds for a little more of a lesser diameter.

I don't have hardly ANY machining capacity, lat alone for special materials, so I am just using the thread, and just for what it is... thread, er, parachute shrouds!. It's just me and my exacto knife against the world (and the awesome power of Elmer's glue)

Oh, and as for nosecones, mine are plastic, thin and hollow. It survived the 100mph impact im mint condition! The same would not have been true if it hit in a parking lot . I get mine pre-made, but I've always wondered how on earth you could make your own? Do you?

wow that's a really good price, can u get me some? I pay quite a bit more than that.

yes I make my own nosecones (usually) I have a small vacuum-former, if the model is too deep for a whole unit I'll make it in 2 halves.

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I have a small vacuum-former

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*is envious*

Here is the site for The Thread Exchange. That's where I got mine. Last spool of that particular size tho. They also Have Nomex and other fancy stuff.

EDIT: heh heh... forgot the quotation stuff

Edited by - Warlord Bob on 30-11-2003 17:08:05

u can get it in sheet form for ur fins and stuff. u can also get it preformed into tube so u can use it for ur fuselage sections. great stuff! (bit pricey though, but when u consider it will last for ages, i think it works out more economical)

I use hardwood for the fins. Not too pricy at hobby stores. Eventualy a beter body material might be nice, so I'll keep an eye out

@Warlord Bob,
It might sound strange but, if you would build your rocket Like I did
make it for the purpose of single step, which means make no parachute,
Just enforce the structures and make the chamber compounds double layered so they can withstand a larger shock. The nose is taking the harder part so Enforce that the most of all, and to ensure the survival of the measurement equipment, don't put that in the highest point of the cone but rather underneath it. Now to make sure it goes up after the modifications you have made use more thrust-Material
(whatever stuff You use for thrust-material) and triple shield the top of that chamber so you won't incinerate the equipment when it fails. Now to make sure that when it stalls, the nose comes down, you should make sure that a 1% increase of weight in the top of the nose is present, so it indeed falls straight down. and if you would,... cancel the chute, if you are not on intent to do that, put it at the end.


Take your time to do this because it will cost a lot more then the standard things you make, not to mention the size. It will get a bit bigger then usual don't be scared of lengths of up to 2 metres/6' 8" because that is normal

(One little secret My biggest was 2,6 metres/8' 8", but due to a little miscalculation of chamber material and too heavy thrust-material it blew up when it got to about 50-60 metres high)

__________________________________________________________
Oh, dear, How sad, Never mind!!-Battery Sergeant Major Williams
Plus the newest addition!!-



Edited by - Locutus on 01-12-2003 02:04:19

Unfortunately the NAR and FAA require you to have a recovery system. They also inspect anything you fly at thier events. Outside of those I don't have a place for high altitude flights. But why would you want to do that anyway?

@WLB, Ehhmmm,... No comment

(Btw, Taw you can let him know by now, over mail that is)

__________________________________________________________
Oh, dear, How sad, Never mind!!-Battery Sergeant Major Williams
Plus the newest addition!!-

"wotchoo talkin 'bout, Willis?" tell him what? if it's "what" I told u he already knows. if it's something else then tell me, cos I don't know!

those "things" I have done in my past I mean

It is OK to tell him, only him.... no-one else!

__________________________________________________________
Oh, dear, How sad, Never mind!!-Battery Sergeant Major Williams
Plus the newest addition!!-

oh no I never even alluded to that