Using Nomex

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lcorinth

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I just got a Nomex parachute protector, "appropriate for rockets up to 2" in diameter" (I think it's 6X6), for a mid power rocket I've just completed - the Quest Big Dog (1.97 inch diameter).

I know how to attach it - shock cord through the button hole - but I'm not sure how I'm supposed to stuff it into the tube, if there's a trick to it. Do I ball it up? Place it flat and open against the top of the tube and then stuff it in? Just stick it in there however it goes and not worry about it? I assume I want the cloth to remain in contact with all sides of the airframe, but other than that, I'm not sure how it's supposed to go in.

Also, do I use it alone, or just as a stretcher for dog barf or wadding?

Thanks!
 
Fold chute in nomex "burrito" style, this will completely encompass/protect the chute on all sides.

I always go one size up over the recommended, to be sure I have enough cloth to do the job.
 
Fold chute in nomex "burrito" style, this will completely encompass/protect the chute on all sides.

I always go one size up over the recommended, to be sure I have enough cloth to do the job.

Hmm... This makes me think I should've gotten a larger size. The chute is an 18 inch nylon.

Well, I'll try it out. If all else fails, I have a ton of dog barf.
 
I tend to use dog barf, even with the nomex. I have several older chute protectors with large burn holes and lots of fraying because I didn't use dog barf when they were new. I use more dog barf with those now.

I've found that if I stuff a lot of dog barf into a rocket, like my Estes Leviathan, it stays in there during deployment and I can use it over and over. The stuff on the bottom turns pretty black and you accumulate the plastic caps from the ejection charges if you are using AT motors, but it will stay and work like a baffle. Protects the chute and doesn't slow down the charge pressure at all.
 
I did a poll on this weeks ago, to see how many wrap the chute burrito style vs. ball up the Nomex like wadding and shove it in. More people wrap than ball. However, the goal is to protect the chute and shroud lines from exposure to flame and burning material. If you can wad up the cloth and get it shoved in there in such a way that absolutely no flame/burning gets through, then mission accomplished. But if you thoroughly wrap the parachute and shroud lines, then there is no chance of burning them.
 
.... But if you thoroughly wrap the parachute and shroud lines, then there is no chance of burning them.

Not true. I have chute protectors and chutes with burn holes in them because they were too close to the charge when it went off. Nomex is not "flameproof" it will get holes burned in it if it's too close to a flame for too long.

Unfortunately there isn't anything bad that has "no chance" of happening when it comes to rocketry
 
I just got a Nomex parachute protector, "appropriate for rockets up to 2" in diameter" (I think it's 6X6), for a mid power rocket I've just completed - the Quest Big Dog (1.97 inch diameter).

I know how to attach it - shock cord through the button hole - but I'm not sure how I'm supposed to stuff it into the tube, if there's a trick to it. Do I ball it up? Place it flat and open against the top of the tube and then stuff it in? Just stick it in there however it goes and not worry about it? I assume I want the cloth to remain in contact with all sides of the airframe, but other than that, I'm not sure how it's supposed to go in.

Also, do I use it alone, or just as a stretcher for dog barf or wadding?

Thanks!

Simply running the shock cord through the button hole... (allowing the Nomex to slide freely on the shock cord) often results in failed recovery when the Nomex slides all-the-way up the shock cord, and "reefs" the parachute making it substantially less effective.

On a light weight rocket like the Quest Big Dog, a "reefed" chute might not be much of a problem. Something of this size/weight can usually "tumble" with a completely tangled chute and survive the landing.

>>> You want to make a habit of running the shock cord through the button hole and TYING it in-place so it cant move. <<<
 
I've been using Borated Duckcloth Canvas as an experiment for a substitute to Nomex, so far the Chute Protector looks good after 5 flights. Canvas was borated using the NFPA formula consisting of Boric Acid and Borax, which iirc is the same treatment given to dog barf by the manufacturers. I do use some dog barf with any chute protector.
 
I've been using Borated Duckcloth Canvas as an experiment for a substitute to Nomex, so far the Chute Protector looks good after 5 flights. Canvas was borated using the NFPA formula consisting of Boric Acid and Borax, which iirc is the same treatment given to dog barf by the manufacturers. I do use some dog barf with any chute protector.

I've been using some auto air bag material as chute protectors also. They handle the explosion and pressurization of an air bag deployment so I figure it might handle our little explosion and pressurization in deployment. I used Aramid thread to stitch the edges and so far, it has worked fine. It's a little stiff and "cracks" in places, but it's lasted as well as my nomex chute protectors and was a lot cheaper.
 
I've been using some auto air bag material as chute protectors also. They handle the explosion and pressurization of an air bag deployment so I figure it might handle our little explosion and pressurization in deployment. I used Aramid thread to stitch the edges and so far, it has worked fine. It's a little stiff and "cracks" in places, but it's lasted as well as my nomex chute protectors and was a lot cheaper.

Been looking to try that recycled airbag stuff myself. The borated duckcloth canvas seems to work so far, however my ejection charges were not directly under it either. To test the inflammibility of the canvas protectors I put my weed burner torch directly onto the cloth for about 10 seconds, the end result was that the cloth didn't catch fire/wouldn't maintain flame but it was brittle enough to break through afterwards. When I do the ground testing for my L2 rocket the charges will end up directly under the canvas.
 
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Simply running the shock cord through the button hole... (allowing the Nomex to slide freely on the shock cord) often results in failed recovery when the Nomex slides all-the-way up the shock cord, and "reefs" the parachute making it substantially less effective.

On a light weight rocket like the Quest Big Dog, a "reefed" chute might not be much of a problem. Something of this size/weight can usually "tumble" with a completely tangled chute and survive the landing.

>>> You want to make a habit of running the shock cord through the button hole and TYING it in-place so it cant move. <<<

Will a simple knot in the shock cord through the button hole do the trick? How far down on the shock cord do you tie the Nomex?
 
I've never tied mine and don't (as of now) plan to. Maybe a disaster will make me change my mind.
 
Will a simple knot in the shock cord through the button hole do the trick? How far down on the shock cord do you tie the Nomex?
What ever you do it will need to prevent the protector from slipping up the recovery harness and fouling the shroud lines. Yes I have had this happen to me. :eek:
 
What ever you do it will need to prevent the protector from slipping up the recovery harness and fouling the shroud lines. Yes I have had this happen to me. :eek:

<<<<. What he said.

This happened to me this weekend, the nomex protector slide up the shock cord and prevented the drogue from opening... So became a nice streamer. Really glad that didn't happen to the main. So for me that was lesson learned and really glad it didn't cost me a 5.5" rocket.
 
Not true. I have chute protectors and chutes with burn holes in them because they were too close to the charge when it went off. Nomex is not "flameproof" it will get holes burned in it if it's too close to a flame for too long.

You have quality of Nomex too, Sunward are very thin and cheap compare to the one sold by Madcow as example.
 
I use a three loop shock cord for my drogue and the chute protector doesn't seem to slide over the loop to bind the drogue. The chute protector is on the main line not the loop, it slides up to the loop and stops, not allowing it to foul the drogues lines.
 
I use a three loop shock cord for my drogue and the chute protector doesn't seem to slide over the loop to bind the drogue. The chute protector is on the main line not the loop, it slides up to the loop and stops, not allowing it to foul the drogues lines.

Ditto. Teddy makes them that way, but you can always tie a loop into two-loop cord and make a third drogue loop that way.
 
In support of Angelo and Sunward, the thinner stuff is for us LPR guys, we don't have all that big a rockets and weight matters.
Angelo is considerate enough to offer everyone something, you just need to know what to buy.
Sunward being our Canadian Brother, has fare prices for his quality. I support Angelo and Sunward fully.
Just my 2 cents worth or worthlessness. :)
 
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