Author Topic: Plant String Build Along  (Read 18470 times)

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Offline swamp monkey

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Re: Plant String Build Along
« Reply #30 on: March 24, 2012, 01:20:21 am »
TIPS:


When rolling fibers you might dampen your palms to get fibers to "catch".  Dry hands won't roll fibers so well.

You can roll a bunch of bundles before hand and grab them as you go.  It does not actually speed things up but it can keep the mess of debarking outside, then you can twist cordage in the living room with minimal mess.

put a small drop cloth under your work area to catch bark. 

Blisters on thumb and forefinger can develop when reverse twisting until you get calloused.

Once you are past the blister stage you can get abductor muscle fatigue.  That muscle between your thumb and forefinger will ache.  It is nature's way to say take a break.

Once you are practiced it is not unusual to make 7-8 feet of cordage in an hour.   10 is possible if you have everything laid out.  But this is not a race.  A rushed bow looks like it and so does a rushed string.  I provide that for time budget purposes only. 

There is a thigh rolling process that is faster.  It does not produce the quality hand rolling does.  Thigh rolling is for making fabric or nets - you know stuff that requires a lot of cordage but not as much strength.

There is also a method I learned using a fishing swivel and hook.  It ripped out 20 feet of quality cordage and made my wrists ache for two days.  Might just be me though.

Dogbane is rot resistant.
Stinging nettle is not.
A High School Science project tested the strength of both fibers before and after repeated wet dry cycle.  This high schooler found that dogbane cord not only did not loose strength but performed better in breakage tests when wet! It increased strength by about 10%.  Nettle initially stronger took a nose dive after being wet/dry repeatedly by loosing 30% of its strength.  The average breaking strength for a two ply reverse twisted nettle cord was 65 pounds.  The average  breaking strength for the dogbane was 40 pounds.  Bear in mind that she did 20 replicates for each string.  The highest strength test for nettle was 116 lbs. and for dogbane it was 98 lbs.    :o

Milkweed's rot resistance is so-so.

Milkweed and dogbane look nice when contrasted in opposite bundles of one cord.  They have similar strength but the milkweed will tend not to twist as much as the dogbane so be mindful of that as you go.

Nettle cordage will be green when fresh but will turn a pale tan after time.   Dogbane stays orange. Milkweed is whiter than nettle cordage.  I mention this if you have cordage made up ready for your next project. 

If you travel for work - consider a small box of cordage making material to go with you.

Consider making cordage ahead of time in at least two thicknesses.  Often when I want cordage I want it right then and am glad to have a bundle in the box ready for use.    [/li][/list]


« Last Edit: March 28, 2012, 06:20:27 pm by swamp monkey »

Offline BowEd

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Re: Plant String Build Along
« Reply #31 on: March 27, 2012, 09:06:47 pm »
Really enjoyed someone familiar making cordage showing a build along.Thank You.I used to make it after unsnapping my hound loose to strike a coon.There are all sorts of time frames to do it in.Never used it for a bow string yet.I suppose it would stretch and take a set like linen and keep it's over all length pretty much.Not being affected by moisture like sinew.Have you done a breaking test on your two ply cordage?
BowEd
You got to stand for something or you'll fall for anything.
Ed

Offline swamp monkey

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Re: Plant String Build Along
« Reply #32 on: March 28, 2012, 10:39:56 am »
i have not done breakage tests on the double braided cord, but might work up a batch just for that purpose.  I have some data on cord breaking strength from a HS science fair project that looked into single cord strength.  I mentored this student on this project and she did a great job.  The results can be found in post #30 of this thread entitled TIPS.  If anyone knows a HS student looking for a science fair project this follow up research would seem to fit!

I figure what ever poundage your bow is, make sure you have a string that is triple the poundage.  So for a 45 pound bow I want cordage that breaks at 135.  Double braiding a cord more than doubles its strength.  I have not measured it directly but reckon  it is less than 1.5 X increase. 

Hmmm.  Perhaps another high school science fair project. ???

One more tip:  Tim Baker's TBB v. II chapter on strings indicates thicker is not always better.  Super thick cords can break easier if they have too many fibers in the single ply.   It is worth a read for clarity on this issue. 

Thanks to you and everyone who has been an encouragement on this!
« Last Edit: March 28, 2012, 06:32:06 pm by swamp monkey »

Offline swamp monkey

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Re: Plant String Build Along
« Reply #33 on: April 15, 2012, 08:24:59 pm »
Cordage on hand can help make pottery paddles used to make cord marked pottery, bind cane splints for a comb, or be used as a handle wrap.