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Fingertrap method: what am I doing wrong?

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rocketsam2016

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I'm trying to use the fingertrap method to create loops at the ends of 9/16" tubular nylon from Madcow, based on the instructions here:
http://www.geocities.ws/rdh82000/Tips/kevlar.htm

At this point I'm using a very long section as you can see in the picture below (the wooden rods are chop sticks that are probably 10" long), but when I cinch the loop tight around something (chopstick, quicklink) and then apply a load, the tail just easily pulls back through the cord. In the picture below, the tail is still coming out the exit hole, but this happens even when I embed the tail inside. Am I doing something wrong or does this tubular nylon just have too big an interior space?

IMG_20170401_113328.jpgIMG_20170401_112257.jpg
 

DavidMcCann

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I wouldn't trust it. You could do it and then stitch down the length with Kevlar thread, but I'd just tie some knots.
 

PatB

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Yeah, the tubular nylon is just too big and doesn't constrict far enough to hold tightly. Finger trapping really only works well with cordage.
 

sl98

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I had the same problem too using 1/8 Kevlar. I thought it was just me. Looking forward to someone who has a solution. Subscribed.
 

markkoelsch

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Do not bother- tie a loop in the end and be done.
 

manixFan

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As PatB says, it's the wrong technique for tubular nylon. I've only ever seen it used on 'open' braided cord where the individual strands can move against each other. For tubular nylon you should use the suggested knots.


Tony
 

watheyak

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It's gotta be braided! The tubular nylon won't "fingertrap" and tighten when you pull.
 

Lowpuller

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Whoops I just read the original post. You can't finger trap tubular nylon.
 

warnerr

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Haven't worked with the flat but on ANY finger trapped method splice I ALWAYS put a few hand sewn keeper stitches using Kevlar thread and a big needle. A finger trap alone can be pulled. The slightest pinch at furthest end and its impossible.
 

rocketsam2016

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Thanks all for the advice. I'm pretty sure I came across posts from the past that mentioned using the finger trap method for tubular nylon, but my observation today matches what everyone is saying here that it isn't going to work. Unfortunately I've specced out my desired recovery harness strength and putting knots in this tubular nylon will bring it below my target, so off to onebadhawk I go for a nice 3 loop one with sewn loops :)
 

Lowpuller

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Just fold it over and sew it together with a box x stitch, you will be fine.
 

rharshberger

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Thanks all for the advice. I'm pretty sure I came across posts from the past that mentioned using the finger trap method for tubular nylon, but my observation today matches what everyone is saying here that it isn't going to work. Unfortunately I've specced out my desired recovery harness strength and putting knots in this tubular nylon will bring it below my target, so off to onebadhawk I go for a nice 3 loop one with sewn loops :)
You can never go wrong with OneBadHawk!
 

Lowpuller

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I should add, I agree, buying a One Bad Hawk harness is also a great way to go. Teddy knows his stuff!
 

Coop

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Also very true. I've got a few Y-Harnesses Teddy made for me and they're wonderful.

Later!

--Coop
 
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