Join Date: Feb 2003
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RE: Homemade string jig?
Here is something I wrote a while back on making Zebra type string (best case).
I have been thinking a little bit more about how to make a Zebra twist two tone, no twist string. I will be needing some new string soon, and I have some high tech string, I forget whether it is 450, or what.
I think the process for making one of these anti-twist strings is so simple it isn't imediately obvious.
I am lucky in that I have a couple of "strongbacks for canoe building, which give me narrow and long work surfaces. But if you didn't have these you could use a piece of two by lumber.
Since we are making a colour string, and lets imagine it is 16 strands total, though I haven't checked into the required number of strands yet, then we will need two nails in the form at the distance appart which the string it to be. It is unlikely that the string will come to the right length on the first pass, so keep careful records, so that you can perfectly estimate the second string. (My approach to this last issue is that my first strings will be new buss cables for a bow I intend to set up with a set of Spot Hog adjusters.) Anyway, make up your two bundles of 8 stands by looping arround the nail spacers, and collect these up. Before pulling them off the nails, take a strand of string or serving, and bind off each of the ends. This will allow the centre of the skeins to look like one bundle, and define handling loops on the ends.
The next (or whenever) step is to develop a bowstring plan, not just how long, but does it devide into two loops/harness at one end, or is it one, where are the servings etc... As part of this you will also know what section of the string is Zebra Twisted. Looking over the string on one 36" bow shows that there are 15 twists in the one colour per 25" of string, or 60%. Take the length of string which will be twisted, and multiply this by .6, for the number of twists/colour.
Here is the cool part: To make your zero twist string, you will have to enter the world of furling, or rope making. Those of you who have previously made a furled trout leader, or a flemish twist bow string are going to have some idea where this is heading. I will describe two methods:
1) mount a hook on a wall, hook a loop from each of your clumps over this hook. Get a piece of arrow stock, about 6" long. Using tape or something build up a big stop on either end about an inch back from the end, to act like a nock, and hold the strings on their repective ends. slip the free ends loop of each bunch over the end of the stick, and spin it one full rotation in your hand, say clockwise. after each turn remove the loops in turn from each and of the stick, and put one counter clockwise turn in them. Someone, or something to hold the accumulating twists down the string towards the hook is necesary. You want each of these accumlating twists to occupy about 1.5", if you let the first few take up a foot or so, it can be difficult to hold them back to the string when you get more and more of them on there, and they won't be even in the finished string.
2) another method is to tie the bundle ends together so that your string is twice as long as it needs to be, put one end over the hook, and then put twice the needed twists into it. Holding the string a full double length somehow, find the middle point, and hang a heavy enough (you may have to try a few weights) weight there. pick up both ends, and watch the string spin itself into the twist pattern. Again, holding back the twist as they build up in the string so they are even. With this method, you will almost certainly need to put more than the actual number of twists you want in the final string, to power the right number in. Experiment. This part of the process is reversible, so you can play with it a bit, as long as you get all of the twists out before youtrie it again. But here is a good starting poont if your string were to be 100" long, then you will have 200" when putting the twist in, that would be 120 twists, even if your finished string only had say 90" with twist in it. To really have a no twist string, I think it is important to be sure the twist areeven, and unforced, or they will want to come out.
I have tried to describe this as well as I can, but the actual tools to do it can be anything you have on hand, right up to a geared hand crank furler. Normally I try not to create too many fixed tools, because I don't have the space to store them. When furling fishing leaders, I often use expedient items like chairs, or paper clips into my carpet to lay them out.
(there is at least a third method, which consists of rolling it up on your thigh, but I will leave that to those of you who are traditionalists)
When you have the right amount of twist in the string, tie off the ends of the twisted area with temporary whips, to keep the twist where you want it. If there are to be split harness elements, they won't be twisted, so comb them out with your fingers.
Now back to your board and your plan. Lay out where the various elements will be. Drive nails, or whatever if there are places where bunches need to be held appart for whipping. This time make sure that your fastener at one end is secure, because we are going to use the bow scale and a come-along to tension the string for whipping.
Whip and complete as usual.
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