Top flight nomex question

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cbwho

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For rocket tubes up to 1-in diameter, Top Flight Recovery sells 3x3-inch nomex sheet with two sheets per package.

Now for the silly question, for a rocket of 1 inch diameter, am I supposed to use both sheets of nomex for the rocket or can I use one sheet for one rocket and one sheet for another?
 

pnobile

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Use 1 of them.

Preston

For rocket tubes up to 1-in diameter, Top Flight Recovery sells 3x3-inch nomex sheet with two sheets per package.

Now for the silly question, for a rocket of 1 inch diameter, am I supposed to use both sheets of nomex for the rocket or can I use one sheet for one rocket and one sheet for another?
 

RocketTree

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Just one. In small diameter rockets, I find the Nomex sheets are a bit tricky to use.
 

crossfire

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Just one. In small diameter rockets, I find the Nomex sheets are a bit tricky to use.
They work best if you can wrap the chute in the sheet than install in rocket
 

RocketTree

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They work best if you can wrap the chute in the sheet than install in rocket
On small rockets, how far up the shock cord from the body tube opening are you attaching the nomex? A few inches?
 

crossfire

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On small rockets, how far up the shock cord from the body tube opening are you attaching the nomex? A few inches?
I would tie off protector and chute just far enough to get both to slid in with enough move for nose cone to fit in well
 

afadeev

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For rocket tubes up to 1-in diameter, Top Flight Recovery sells 3x3-inch nomex sheet with two sheets per package.
Like others have said, this is just a 2-pack sale packaging. Use 1.

Now for the silly question, for a rocket of 1 inch diameter, am I supposed to use both sheets of nomex for the rocket or can I use one sheet for one rocket and one sheet for another?
1 per rocket.
For larger diameters, there are 4x4", 6x6", 9x9", etc Nomex blankets:

They work best if you can wrap the chute in the sheet than install in rocket
I never found that to be feasible in sub-2.6" rockets. The overall space inside the airframe is just too tight to wrap a burrito around the chute, and still have room for it slide out easily.
Especially true for 1" rockets.

On small rockets, how far up the shock cord from the body tube opening are you attaching the nomex? A few inches?
I slide the nomex blanket as far down towards the FWD end of motor mount, as possible. Folded chute goes right on top.
During acceleration, the chute and shock cord will be pushed down the airframe anyway, and this way I can control that placement of the Nomex blanket to provide well-positioned barrier to the ejection gas cloud.

a
 

crossfire

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Like others have said, this is just a 2-pack sale packaging. Use 1.



1 per rocket.
For larger diameters, there are 4x4", 6x6", 9x9", etc Nomex blankets:



I never found that to be feasible in sub-2.6" rockets. The overall space inside the airframe is just too tight to wrap a burrito around the chute, and still have room for it slide out easily.
Especially true for 1" rockets.



I slide the nomex blanket as far down towards the FWD end of motor mount, as possible. Folded chute goes right on top.
During acceleration, the chute and shock cord will be pushed down the airframe anyway, and this way I can control that placement of the Nomex blanket to provide well-positioned barrier to the ejection gas cloud.

a
Dont you end up with a lot of burnt chutes doing it that way. The burotio wrap really protects the chute much better
 

Funkworks

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I would tie off protector and chute just far enough to get both to slid in with enough move for nose cone to fit in well
Why tie the nomex? I just leave it free to slide along the cord between the body tube and the chute.
 

crossfire

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Why tie the nomex? I just leave it free to slide along the cord between the body tube and the chute.
Sometimes the nomex will slid up over shroud lines and collapse the chute
 

afadeev

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Dont you end up with a lot of burnt chutes doing it that way. The burotio wrap really protects the chute much better
Zero burnt chutes on smaller rockets protected by a Nomex square (vs. ~15% damage rate with disposable wadding or dog barf).
Burrito chute wrapping is simply not an option on smaller diameter airframes. There is just no room.

The answer changes for larger airframe HP rockets.
 
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cbwho

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Launched with nomex squares in my 1 inch diameter tubes with my Top Flight chutes in 15F cold. Chutes deployed perfectly without burn marks. ( To attach the nomex I simply poke a loop of shock cord through and loop the nose cone thru the loop. )

One issue though, I noticed one of the nomex sheets is now brittle and torn from the blast. How many launches is the nomex supposed to last? I pushed the square in as a V pointing towards the engine.
 

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Banzai88

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Launched with nomex squares in my 1 inch diameter tubes with my Top Flight chutes in 15F cold. Chutes deployed perfectly without burn marks. ( To attach the nomex I simply poke a loop of shock cord through and loop the nose cone thru the loop. )

One issue though, I noticed one of the nomex sheets is now brittle and torn from the blast. How many launches is the nomex supposed to last? I pushed the square in as a V pointing towards the engine.
All depends on proximity to the charge and how large that charge is. The orange nomex that is popular with rocketry should last a good long time, lots of ejections, and is washable.

If you find that your placement or technique is burning holes in your nomex, supplement with some dog barf. I have some nomex blankets that have a hundred or more ejections on them.
 

cbwho

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All depends on proximity to the charge and how large that charge is. The orange nomex that is popular with rocketry should last a good long time, lots of ejections, and is washable.

If you find that your placement or technique is burning holes in your nomex, supplement with some dog barf. I have some nomex blankets that have a hundred or more ejections on them.
Dog barf defects the purpose! Why bother with litter free nomex if you add barf!?!

Where do you place the nomex?
 

teepot

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I either wrap the chute up in the blanket or on smaller diameter tubes I let the chute push it in so it is in close proximity to the chute. I also use wadding or dog barf. Both are biodegradable.
 

SharkWhisperer

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Dog barf defects the purpose! Why bother with litter free nomex if you add barf!?!

Where do you place the nomex?
Curious what makes you think that Nomex, or any meta-aramid (aromatic polyamide) polymer, is litter-free, aka biodegradable? Yes, it's somewhat sensitive to UV light/sunlight, just like the para-aramid relative Kevlar, but "litter-free"/biodegradable?

It's not paper or cellulose, both of which are most definitely biodegradable.
 

cbwho

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Curious what makes you think that Nomex, or any meta-aramid (aromatic polyamide) polymer, is litter-free, aka biodegradable? Yes, it's somewhat sensitive to UV light/sunlight, just like the para-aramid relative Kevlar, but "litter-free"/biodegradable?

It's not paper or cellulose, both of which are most definitely biodegradable.
The nomex is litter free since it is attached to the ejection cord and not left as litter at the launch site. Biodegradable is not a requirement of litter free.

Dog barf leaves litter as I doubt you pick up every last piece of it. I do pick up Estes wadding when I see it.

The whole sensible point of nomex is to be litter free (at least I thought) but if it lasts only 1 or 2 launches then it fails the reusability metric of 10 launches. If one adds dog barf then why bother with nomex??
 

teepot

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I'm surprised at the damage you are describing. I have nomex squares and blankets that have had a dozen or more launches that are only dirty. No tears, no burn thru or have they become brittle. And I can't think of a reason why one launch would do that to the nomex. It just occurred to me that my nomex is either Dinochutes or Sunward. I don't have any Top Flight nomex. But they can't be that much different. Anybody else have an idea?
 

JoePfeiffer

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Launched with nomex squares in my 1 inch diameter tubes with my Top Flight chutes in 15F cold. Chutes deployed perfectly without burn marks. ( To attach the nomex I simply poke a loop of shock cord through and loop the nose cone thru the loop. )

One issue though, I noticed one of the nomex sheets is now brittle and torn from the blast. How many launches is the nomex supposed to last? I pushed the square in as a V pointing towards the engine.
Are you sure it's really Nomex? I've noticed some chute protectors are described as Nomex, and others just say "fire retardant" without actually saying they're Nomex. Could you have the latter?

Edit -- ah, you did say Top Flight. The product page says fire retardant, and mentions Nomex thread. I'll guess the fabric itself isn't, just the stitching on the edges.
 
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jrap330

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The nomex is litter free since it is attached to the ejection cord and not left as litter at the launch site. Biodegradable is not a requirement of litter free.

Dog barf leaves litter as I doubt you pick up every last piece of it. I do pick up Estes wadding when I see it.

The whole sensible point of nomex is to be litter free (at least I thought) but if it lasts only 1 or 2 launches then it fails the reusability metric of 10 launches. If one adds dog barf then why bother with nomex??
Gee , you are an enviromentalist, who is wrong, the purpose of Nomex is a reusable protection that hopefully provides better protection then wadding and save money. Not that it adds to litter. Dog bawf is so loose, spongy, and light, I bet it degrades within weeks, reminds me of Scott's patchmaster seeds.
 
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