How do you terminate Kevlar cord?

[slothead]

With nylon all you do is apply a flame to it to cauterize it so it won't fray, but what do you do to Kevlar to keep it from fraying? Anything similar?

 

[Maxwelljets]

Wood glue works amazingly for keeping kevlar from fraying. You don't need much, and you only need it right at the end.

 

[Keisling]

Wood glue works amazingly for keeping kevlar from fraying. You don't need much, and you only need it right at the end.

+1
I use a couple wraps of masking tape to keep it together while I cut it to length, it's much easier to cut that way. Once cut, I dab some wood glue on the ends while the tape still holds everything together.

 

[slothead]

Thanks guys. I assume by wood glue you mean something like TBII, right? I’ve got a bottle on the shelf right next to the epoxy.

 

[Maxwelljets]

Yeah, titebond works. Pretty much any of the standard light tan colored woodworking glues will work.

 

[thequick]

a few drops of thin CA.

 

[Onebadhawk]

I use hi tack masking tape before the cut
then a drop of CA into the cut end..

Teddy

 

[lakeroadster]

I tie a knot in it, then cut off the tail tight with the knot.

 

[dhbarr]

I use medical tape and then cut it. Stays very flexible and can be undone.

 

[slothead]

Lotta great ideas here guys. Thanks. I love this place!

 

[JohnCoker]

Before I cut it (which is also a PITA), I mark a line across it with a Sharpie. Then I saturate that line area with CyA. When it cures, I cut the line and have two neat ends.

 

[slothead]

All good stuff guys.

This afternoon I decided to do a short test (between NASA telecons). In a previous life I was a senior scientist at Orbital Sciences and I've done my share of lab testing. So today, since I know virtually nothing about Kevlar fabric tubing, I decided to do a flame test of a small piece of Kevlar that was sent to me as advertising from Giant Leap. I used a backyard grill lighter as the heat source. Butane (what powers the grill lighter) burns at about 3500F I'm told, so it would easily prove the fireproof characteristic of Kevlar in the presence of a black powder ejection charge (black powder burns pretty cool at significantly less than 1000F). And while it appears that I can't upload the video (or don't know now), I'll report that the Kevlar did not catch fire and any "embers" (one very tiny one) extinguished itself in seconds.

I did NOT test the Kevlar after saturating it with CA.

(If anyone would like to assist me in learning how to posting a video, I would be very appreciative.)

 

[Wallace]

Heat shrink tubing with sewn loops is my go to method.

 

[thequick]

I use dremel tool cut off wheel when cutting (glue before cutting). Never a problem.

 

[snrkl]

I’ve had issues with thin CA wicking too far into the Kevlar. It can also leave a chute piercing sharp end sometimes.

My go-to method now is to tie two overhand knots next to each other and cinch down tight, then cut between them.

Once looped etc, I cover the ends with heat shrink tube that I colour code to make field assembly a little more “idiot proof”:

 

[JohnCoker]

My go-to method now is to tie two overhand knots next to each other and cinch down tight, then cut between them.

The traditional knot for this is a bowline.
https://www.animatedknots.com/bowline/

 

[Wallace]

The traditional knot for this is a bowline.
https://www.animatedknots.com/bowline/

Agreed: How to deal with the frayed ends. Glue makes kevlar brittle. Safe bet it's not friendly with nylon either but at least you have the heat option.

 

[Maxwelljets]

Agreed: How to deal with the frayed ends. Glue makes kevlar brittle. Safe bet it's not friendly with nylon either but at least you have the heat option.

The reason I prefer wood glue over epoxy or superglue for terminating kevlar is because it is significantly bendier when dry. The kevlar doesn't get anywhere near as brittle.

 

[snrkl]

The traditional knot for this is a bowline.
https://www.animatedknots.com/bowline/

I was just talking about end fray protection when cutting.

For attachment, I typically use a figure 8:

https://www.animatedknots.com/fig8follow/index.php

 

[Wallace]

Cut it with something sharp?

 

[Eric]

Couple wraps of 1/2" masking tape. Sharp new razor blade against a flat hard board. Cuts clean.

 

[FredA]

heat shrink

 

[deweylandrum]

I use dremel tool cut off wheel when cutting (glue before cutting). Never a problem.

I try to make sure I'm using my wife's best sewing scissors to cut with. They're usually really sharp....

 

[o1d_dude]

I use these to cut kevlar. You can order them through Amazon for about $13.

Very sharp and I do not use them for anything other than cutting kevlar.

==>> Jonard JIC-186 Kevlar Ergonomic Fiber Optic Cutter, 6" Length

 

[OverTheTop]

Heatshrink, particularly the stuff with the hot-melt glue inside.

 

[gdiscenza]

I saw the title of the thread, and my brain immediately went to:

I call it into the HR manager's office for an exit interview while security cleans out its cubicle and disables all associated computer accounts. I retrieve any corporate-owned equipment and badges and have it escorted from the office.

I've been in the corporate world faaar too long...

Gregg

 

[dhbarr]

I saw the title of the thread, and my brain immediately went to:

I call it into the HR manager's office for an exit interview while security cleans out its cubicle and disables all associated computer accounts. I retrieve any corporate-owned equipment and badges and have it escorted from the office.

I've been in the corporate world faaar too long...

You are not alone, but I do hope the cause for termination was reasonably well documented.

 

[Bill Heath]

The traditional knot for this is a bowline.
https://www.animatedknots.com/bowline/

Why would you want another knot as opposed to tape or heatshrink. Also, I worked at sea and bowlines were never used as end line knots.

 

[gdiscenza]

You are not alone, but I do hope the cause for termination was reasonably well documented.

I'm in Virginia, a right to work state. The documentation could be as simple as "The sky is blue, you're fired"

Gregg

 

[deweylandrum]

I try to make sure I'm using my wife's best sewing scissors to cut with. They're usually really sharp....

I was just kidding...my wife would kill me if I used her sewing scissors for anything. But I did just purchase the kevlar cutters that O1d_dude posted.....