String Length

dvd8n

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Ok, so I have a string which is twisted to the right length for my bow but with far too many twists in it; I want to copy it but I want to make it with a sensible number of twists in it.

I'll put it on my jig twisted then extend the jig a bit to allow for twisting.

My question is: how much extra length do people recommend so that I end up with a sensible number of twists in my string?

I ask because of my huge collection of strings that are a little too short or long to use on any of my bows; making a string of the correct length just isn't something that I seem able to master :hissyfit:
 


Rik

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Make a string the same length as the twisted string? When it stretches, twist it to get back to length... You might not end up with enough twists, so then you know you need slightly longer.
The rule of thumb I've followed in the past is that 0.5cm of string length equals 1cm of bh (the units aren't important, it's a ratio), so if you keep note of the original length of the untwisted, unstretched string and how it ends up, it shouldn't take more than a string or two to get right.
 


geoffretired

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Supporter
If your current twisted string is the right length, why not take out twenty twists from it, then put it on the jig. Adjust the jig for that length and make the new one on those settings. The string will be too long, but 20 twists should bring it back to where you want it.
I say twenty twists, but you could use 30.
 


Mark31121

Member
Ironman
I made a string a couple of weeks ago and I couldn't remember the length - I put the one on off my bow (I the twists) on to the jog and added 3/4 of an inch for the new string and that worked well, it's a two tone string so the twists are quite obvious.
 


dvd8n

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If your current twisted string is the right length, why not take out twenty twists from it, then put it on the jig. Adjust the jig for that length and make the new one on those settings. The string will be too long, but 20 twists should bring it back to where you want it.
I say twenty twists, but you could use 30.
I thought about doing this myself but decided against it as I have found that the amount of adjustment that you get from a twist is not really linear. I find that the first twists that you put in do very little but by the time that you get a lot of twists in the string one more has a big effect, especially when you get to the point of having way too many twists in the string. But thanks for the idea.
 


dvd8n

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I made a string a couple of weeks ago and I couldn't remember the length - I put the one on off my bow (I the twists) on to the jog and added 3/4 of an inch for the new string and that worked well, it's a two tone string so the twists are quite obvious.
Thanks. I'll go with that to start, then use Rik's input to adjust if it's a bit long.

If only the material wasn't so expensive.............. :rolleyes:
 


geoffretired

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With the method I mentioned, the non linear aspect will mean you need to put in more than 30 twists if you unwound 30 from your current string.
If you unwind 20 you will need to twist on more than 20 on the new string. But a few more than 20 must be far less than the number you have in already.
 


dvd8n

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With the method I mentioned, the non linear aspect will mean you need to put in more than 30 twists if you unwound 30 from your current string.
If you unwind 20 you will need to twist on more than 20 on the new string. But a few more than 20 must be far less than the number you have in already.
Yes, I guess that you are right :D
 


geoffretired

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Heehee, I am aware that there are several methods to reach the same end. It is interesting to read how others would go about the task. Also, it is interesting to find out which option people choose, and why.
A simple, but wasteful method would be, to make a shorter one than the current one( untwisted) without considering too carefully how much shorter, and see what happens. Or make a longer one than the current (twisted) one and see what happens.
Anything else, requires a bit more planning in the hopes of getting closer to what is wanted, with fewer big errors; or less waste of time/materials.
It might work, if you totally untwist your string and see how long that is. Then add 20 twists (or 30) and see how much it has shortened. Use that to judge how much longer to make your new string. That would take very slightly longer than the method I mentioned. And it may be very slightly more accurate.
How accurate does the finished string need to be, with regard to number of twists? How different is a 20 twist string from a 30 twist string? Heehee.
 


dvd8n

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Unfortunately I seem to be a master of making strings that are fractionally too short or need way too many twists in them.

I guess that it's something that gets better with experience but unfortunately the screwups make me feel less like trying again, thus not gaining the experience needed.
 


Mark31121

Member
Ironman
if it's slightly too long do you have any excess on the loops? When I first made a string for my Hex's I didn't realise I needed to shrink the loops and I was suprised how much difference it made.
 


geoffretired

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The lucky ones get it right first time and copy it for all the rest. Bit like archery really; get a gold and keep copying it.
 


dvd8n

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Okay......

I put my string on the jig and marked it, intending to add a bit less than an inch for twisting. Then I thought about what Geoff said so I untwisted the string 20 turns and put that on the jig; that came in at about an inch longer too, which was encouraging. So I added the inch and made the string.

At first I thought that it was too short, but no - 36 twists put the brace point just where I wanted it.

So it's on the bow stretching at the moment. Hopefully it won't stretch too much. Three quarters of an inch would probably have been fine too :D

So I guess it is possible to make a string in one go after all.

Thanks everyone :)
 


dvd8n

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if it's slightly too long do you have any excess on the loops? When I first made a string for my Hex's I didn't realise I needed to shrink the loops and I was suprised how much difference it made.
I do try to keep the loops as small as possible; on my first pair of Borders I was quite alarmed at how the string always seemed to be about to fall off the nocks. It never happened though.
 


geoffretired

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Nice news. So, does 36 twists look about right as far as the appearance of the string? I'm a bit surprised that 20 turns made 1" difference; but you did say earlier that the string quickly shortened when there are already lots of twists in it.
 


dvd8n

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It looks fine but I'm hoping not to have to put too many more in to accommodate stretch.
 


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