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Shock cord for HPR build

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rockets

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I need some shock cord for my LOC Graduator 38mm DD. I will need probably about 20 feet.
I'm not sure what's best to have, tubular nylon or kevlar.
I don't want anything too wide, as it may zipper my BT.
I'm preferably looking for the lowest price.

Thanks,
 

Wayco

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Best price will probably be tubular nylon, and since it is wider, it will be less likely to zipper your rocket. With a dual deploy system, zippers are less likely to occur. Since my L2 rocket failed it's first certification flight due to a scorched TN shock cord, which separated when the main opened, most of my rockets use kevlar. Takes up less space and doesn't melt if exposed to ejection charges. A bit more expensive though.
 

djs

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I used some small diameter tubular kevlar in my recently built Loc starburst (2x24mm motors, 2.6" diameter). It works great, and I know it won't snap. Note- I did make the shock cord super long, as you can see with the picture at the end of this video:

[video=youtube;PfoPz0RisOM]https://www.youtube.com/watch?v=PfoPz0RisOM[/video]
 

djs

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Longer is more betterer Glen...

Teddy
That's always my theory.. we have very tall trees, and my philosophy is longer shock cord = more likely chance to stumble across the shock cord when looking for the rocket.
 

Onebadhawk

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I think it was Matt the young man from the southeast,, South Carolina maybe,,
someone asked how long the harness should be,,
he said 5 ft longer than the tallest tree,, lol...

Teddy
 

rockets

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Lol...
Tank you man...

Check this..

https://onebadhawk.com/light-kevlar.html

1/8" Tubular Kevlar X 50 ft fer $12..

This is what I use on a 38mm airframe...
And you'll get many harnesses out of 50 ft..
Best material for the application, best price around...

Teddy
OK I'll have to consider that for the future... That looks like a great deal!
But, I already have a deal going on currently with another member.
But, don't worry, I always seem to be building scratch-builds, and need shock cord. :p
Thanks,
 

blackbrandt

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I think it was Matt the young man from the southeast,, South Carolina maybe,,
someone asked how long the harness should be,,
he said 5 ft longer than the tallest tree,, lol...

Teddy

Yup. And it's north carolina (soon to be Alabama, in 8 days :) )
 

OverTheTop

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I use TN due to the compliance of the material. Kevlar will only stretch 6-8% and then fail. Nylon will tolerate a lot more stretch than that.

I have a strategy to help with not flossing your airframe. Check out the link here for an explanation:
https://forum.ausrocketry.com/viewtopic.php?f=6&t=4612&start=78

Kevlar or nylon, just make a choice and think through how to make it work for you.
 

Onebadhawk

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Yup. And it's north carolina (soon to be Alabama, in 8 days :) )
Heyyyy,,
How are you Matt..
Still perusing huh,,lol..
Good for you man..
You're going to do wonderful in your new school...
Just keep your priorities in order and respect your future...

I'm jealous Matt,, lol...

Teddy
 

rockets

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FOUND! Onebadhawk has taken care of me!!!

Thank you all for your other GREAT offers!! :)

Thanks,
 

Onebadhawk

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Andrew,,
In your email to me you asked for my address to send the money
for this 1/8" Tubular Kevlar harness material...
You don't owe me anything as your outstanding balance with me has been paid...
I am shipping to you right now...
I'll send you your paid invoice with tracking info in just a minute...

Teddy
 

Onebadhawk

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OK Andrew,,
Your order is shipped..
You should have the invoice with tracking info in your email..
Thank you Andrew..

I have said many times,,
this community is just so nice it's unbelievable...
When someone is in need,,
there is always an outstretched hand...

Teddy
 
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