String jigs; another take.

[geoffretired]

I have read the recent thread on jigs and didn't want to sidetrack that one.
I make strings on an old homemade jig. It is strong enough to allow me to wind the string round and get fairy even tension on the winds.
After that I can roll the string around the jig to even out the tensions.Just stretching the string can make a slack strand "look" as tight as the rest, but remove the tension and it is still a slack strand. I think the friction between the strands, especially at the end posts, tends to fix the relative lengths/slacknesses of individual strands. Rolling the loop around the jig gives each strand a chance to move a little in relation to the rest.It is the movement, in relation to the other strands in the loop, that evens the tensions. Twisting and stretching can then be managed with a hook on the wall and a weight.
So, does a string making jig really need to be so strong? I am not saying that rigidity is not necessary, just wondering about how much is needed to make a good string.

[not dead yet]

if its not rigid how do you get tight end servings.....i always do the centre serving on the bow

[geoffretired]

Hi Not dead yet,
I understand what you are saying. I think my post wasn't clear enough.
I could add struts to my jig which would significantly increase the rigidity.
However, when I wind the string round the posts, I am fairly gentle with the string tension, trying to keep it all the same. If I accidentally, pull too hard on one circuit, it shows up as the previous windings sag. I unwind that last part and redo it. Once the winding is complete, I roll out any remaining unevenness and then adjust the posts at one end to add more tension ready for the end servings. Adding tension to the string at that stage, does not even out the tensions, it just makes it easier to serve. I can create enough tension to do that, but not enough to stretch a string, as mentioned in the other thread.
I think a very rigid jig is really only necessary if you intend to use it to make then stretch the string using very high tensions.

[bimble]

At the end of the day it mearly has to bit slightly more rigid than it needs to be. You (Geoff) use a homemade jig for your strings, you know how much tension your putting it under and therefore how much the jig needs to take. But a commercially built jig that you buy in the shop, well, they don't know how much force it's going to be put under by the person using it, so they have to factor that in and over-enginer to be on the safe side.

[geoffretired]

Hi Bimble,
I agree with what you are saying; though it seems some manufacturers build in less rigidity than others.

[phillc]

Having made recurve strings for a few years and changing to compound I have started to make my own strings / cables the first attempt on the string seems to work ok but finding a suitable wieght was a bit fun and leaving a string hanging for a while was not popular at home then I came up with a neet space saving jig ( I now have three made up string control and buss)

M10 threaded unistrut with a length of the sleeving to fit it, on the end of the thread a nut with a hole drilled to take an m4 bolt same thing on the opposite end of the sleeve drill thorugh the tube a couple of washers an a nut. make the string as normal transfer to the jig wind the nut into the end of the tube to stretch the string makes a very even pressure on all strands if not twisted before then serve twist and put back on again . I tried with m8 bar and it was too bendy if you pm me your e mail address I will send some photos. All of the bits are available from electrical or plumbing suppliers