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sewing kevlar

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BlueNinja

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Has anyone sewn 1/4" kevlar before? I need to make some small lops in the end, a)what should I sew it with, some untwisted kevlar thread? and b) will it be strong enough? finally, c) should it be hand sewn or machine sewn?



Blue
 

rocketsonly

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Most of the presewn shockcords that's I've seen used Nomex thread.
 

Ryan S.

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I just double the kevlar back on itself and tie a knot, this then forms a solid loop. I have also done this sucssesfully on 9/16 and 1" tubular nylon
 

DynaSoar

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Originally posted by Ryan S.
I just double the kevlar back on itself and tie a knot, this then forms a solid loop. I have also done this sucssesfully on 9/16 and 1" tubular nylon
That's what I've always done on all shock cord of all sizes. That knot tightens against itself when pulled, making it tighter and won't slip, and since it's squeezing on itself and not infiltrated by anything, less likely to break.

Plus, you can push that loop through a screw eye, snap swivel or another loop on another piece of cord, pull the eye/swivel/cord up through the end of the loop stuck through, and when that tightens on the piece it's looped through, it's two widths of the material doing the tightening. Again, less likely to break there.
 

jerryb

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Originally posted by Blue_Ninja_150
Where can you get nomex thread?

Walmart had kevlar fishing string.... in the sporting goods isle... not sure how good it would be at sewing thread... they say it dont knot work a ****...

one of my saltwater buddies tried a spool of it... its VERY thin for its strength... but then again..it IS kevlar...

later
Jerryb
 

kgholloway

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For Kevlar thread go to:

http://www.mcmaster.com

and order their catalog number 8800K41

It's a 300 yard spool of Kevlar thread and costs $11.32



For forming loops in Kevlar try "splicing" the TK back upon itself by pulling about 6" of the end into and through the center of the standing portion of the TK. This is difficult to describe but easy to do using a small rod made out of a coat hanger and some masking tape to pull the end of the TK through the center of the line. See if you can find a book on seamanship such as Chapman's or an experienced sailor to help you out.

Here's a picture from the rocketry materials site of what I'm talking about:

http://www.rocketmaterials.com/data/cord/BB_Pratt_DeH8_Loop1.JPG
 
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