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  1. #1
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    Default string making question

    When making a new bowstring when do you put the twists in and how many is needed? Do you make the string a little long when setting up the jig to allow for the twist? Do you serve the end loops before putting in the twists?

  2. #2
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    For a string up to 75'' I add 5/8'' then put the twist in it to get it to length. After that I streach it & put more twist in it to get it to length.

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  3. #3
    Shoot already... Sheesh! Rhino's Avatar
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    When I build strings, the first thing I do is calculate the length I need to set my jig at. To get this number, I take the finished length I'm trying to make, figure out how many twists are going to be in it, and add the extra those twists are going to use.

    I like to make my strings with 1 twist for every 1.25" of overall length. So, if I'm making a 60" string: 60/1.25=48 twists. I've found that in this range, each twist will amount to approximately 0.02". 48 twists * 0.02=0.96". This is just an average, the more twists there are, the faster each twist will shorten the overall length, but it will get you darn close. So I would add 1" and set my jig to 61" for a 60" finished length string.

    With the jig set at 61", I will lay out the desired number of strands, open the posts up and serve the end loops. I like a 3/4" loop for my bows, so I serve for 1.5" (leave the serving jig on the string) rotate the posts back, center the serving around the end post and continue serving to close the loop. I use 5 wraps, then 10 back wraps to finish. Cut and melt the serving. Repeat on the opposite end. This will leave you with a very clean looking loop on both ends.

    Next it's time to add the twists. Something I've found to be very important when twisting is to use a pair of splitters. I made mine out of nylon washers. One large washer sandwiched between two slightly larger washers with bolt and nut holding them together. Split the strands in the true middle or by color if making a two color string and slide the splitters to each end. What this does is as you begin to twist, it forces the string to cross in the center and twist toward both ends evenly. If you twist with no splitters, the twists will begin at the end you are twisting and work toward the other end leaving the string unbalanced with more twists in one end than the other. Also if you are making a two color string it makes it very easy to get a nice looking twist. One side note: before adding any twists, for the bowstring itself, I will insert a scrap piece of string approximately where I want the peep sight to be to make finding the center easier later, and another where I want to start the center serving.

    Now that all your twists are in, remove the splitters and insert the end of your center serving material at your starting point (saved by that scrap piece of sting) and crank up the tension. The reason for inserting the center serving tag end now, is that once the string is stretched, I want to put on all the servings under the same tension without having to back it off to insert the serving material. I made my own stretching system with some angle iron, eye bolts and S hooks. It attaches right to my jig base and by tightening the nuts on the eye bolts I can add tremendous tension to the string.

    The next step is to burnish. I use a piece of release rope (or D loop material) and wrap it around the string, pull tight on both ends and work it back and fourth up and down the string. This is going to compact the strands and remove excess wax. It's also going to make the string a bit longer, so crank the tension back up and do it a second time. This step is huge in controlling peep sight rotation and virtually eliminating break in time.

    Now, you've got end loops served, twists added, string burnished and under high tension. To start the end servings, I put the tag end through the end loop, serve over the 15 loop closure wraps and continue to the desired length. By going through the end loop, this will anchor the serving and prevent it from sliding/separating.

    Now all that's left is the center serving. Sometimes I'll run the tag end the entire length of the center serving, and sometimes not. It all depends on which combination of materials I'm using, and what arrow nock will be going on to it.

    One final check on the overall length, add a couple of twists if needed, and it goes right from the jig to the bow.

    Cables are basically the same. For split yolk cables you can either make a floating yolk like Hoyt uses which consists of two separate pieces, or a static yolk. I've kind of settled on the floating yolk myself, but when I make a static yolk, I make the cable twice as long, and half as many strands as I need. Serve the loops on both ends (usually 1" loops here) and then fold it in half to make the yolk and serve another loop on the new end. Although rotation isn't really an issue with cables, I still go through the steps with the splitters, burnishing and stretching. Using this method, once the initial timing is set, it's fairly unusual that I have to adjust it any further.

    Hopefully that answers some of your questions. It seems like everyone does things a little different, but this is what works best for me.

    Good luck!
    >>>~~~~~~>
    Don't worry what people think... They don't do it often.

  4. #4
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    Excellent discription by Rhino. There's a lot of good information in that post!

    But for the simple answer to your question, serve the loops, then twist.

    Length between posts to account for the twists will vary with each string builder because we spin the string with different tension.

    Most just waste a string or two to learn their own tendencies. Personally, I set the posts at exactly the distance that I want the string to be and don't use a lot of tension while spinning. It works for me, but likely won't work for you.

  5. #5
    Senior Member JAVI's Avatar
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    Quote Originally Posted by Allen View Post
    Excellent discription by Rhino. There's a lot of good information in that post!

    But for the simple answer to your question, serve the loops, then twist.

    Length between posts to account for the twists will vary with each string builder because we spin the string with different tension.

    Most just waste a string or two to learn their own tendencies. Personally, I set the posts at exactly the distance that I want the string to be and don't use a lot of tension while spinning. It works for me, but likely won't work for you.
    Yep..
    Mike "Javi" Cooper

  6. #6
    Shoot already... Sheesh! Rhino's Avatar
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    Quote Originally Posted by Allen View Post
    Personally, I set the posts at exactly the distance that I want the string to be and don't use a lot of tension while spinning.
    Interesting. I'm guessing that you don't have many twists in your finished strings as you would only be able to twist enough to accommodate the stretch before you arrive at your desired finished length.

    I never used to put in as many twists (or add as much length) as I do now. The way I arrived at my current method was to de-construct a Winners Choice string. I put the string on my jig, cut off the servings and recorded all the measurements including twisted and untwisted lengths, how many twists, as well as direction of serving related to direction of string twist. Then I was able to adapt that information into the formulas I use for the materials I prefer. I used to have issues with consistency from string to string. Overall length was always good, but peep sight rotation was a problem. Some were acceptable, but many were not. The strings I make now have zero rotation, and because of the pre stretching and burnishing under tension that I do, overall length stays consistent and break in time is eliminated.

    One thing I didn't touch on in my previous post was direction of twist. I've done it, and seen it done both ways, but to make the most consistent strings you have to look at the individual strands of string material. Any material that is a blend, is twisted together at the strand level. You want to twist your finished string in this same direction so as you add twists you are tightening the fibers in the individual strands as well as the entire bundle. If you twist opposite of the strands you will be tightening the bundle, but loosening the strands and that can create rotation issues as well as overall length and stretch problems.

    As far as tension, I couldn't say exactly how much I put on except that it's far more than the string will see while on the bow. I put my servings on pretty tight, so I use enough tension so that the string will not rotate as I am applying the servings. That way the tension is completely even from end to end underneath all the servings.

    I've also made a couple of additions to my jig in order to beef it up so it won't flex. First, I doubled up the base by adding a second stick of U-channel bolted under the first. Then I added a 8' x 8" x 1/8" steel plate between each of the spindle bases and the jig base. This prevents the spindles from rocking on the base which is especially important while laying out the strands. If the end spindles are leaning toward each other instead of remaining parallel, the string strands will get shorter as you wind them on working up the spindle. That creates loose strands in the finished string. This is not as noticeable with a string made out of a material with some stretch because the strands will equalize in length under tension. But with the no stretch materials like 452X, it can be a problem.
    Don't worry what people think... They don't do it often.

  7. #7
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    Default string making (twisting)

    After servving the ends (eyes) do you remove one eye off the jig and twist from the lose end eye, or do you leave it on the jig and put your twister in the center and do the twists from the center? I would think that twisting from the center would be more even, but thats what Im not sure about. Thanks for the great info on this string making question.

  8. #8
    Shoot already... Sheesh! Rhino's Avatar
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    After I serve and close the loops, I insert my splitters on both ends, leave one end on the jig and twist from the other end. With the splitters on both ends, that forces the string to cross in the middle and twist toward the ends from there.

    My "twister" basically consists of a tool I have that looks like an awl with a hooked end on it. I would recommend using some sort of hook through the end to do your twisting, because that makes it easier to maintain some tension while twisting as well as keep track of how many twists you are putting in.

    >>>~~~~~~>
    Don't worry what people think... They don't do it often.

  9. #9
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    Rhino,

    That's a good tip on twisting the bundle the same direction as the individual strands. Thank you!! I'd never heard that before, but it makes sense.

    On the rate of twists, I used to put in more twists than I do now. As much as one per inch. However, both Brownell and BCY recommend less, about one twist per 2 to 3 inches and I tried it that way. I really couldn't see any difference in peep rotation or anything else with the fewer twists. Do you see any difference with more twists?

    Good stuff on string building. Thanks for posting

    Allen

  10. #10
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    Well I can't see all that good so which direction do the strands of bcy 452x twist?

  11. #11
    Shoot already... Sheesh! Rhino's Avatar
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    Quote Originally Posted by Allen View Post
    Do you see any difference with more twists?
    I've settled on the 1 twist per 1.25" of string for a couple of reasons.

    1. That's about what the WC strings I have used are, and I've had great luck with those.

    2. I don't serve my peeps in above and below. I only tie around the groove in the peep and the 1 per 1.25" twist keeps it in place very well.

    3. With less twists, it seems like twists added to adjust peep sight location (rotation wise) are partially absorbed in the string which means I needed to add more twists to make a real difference.

    >>>~~~~~~>
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  12. #12
    Shoot already... Sheesh! Rhino's Avatar
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    Quote Originally Posted by jim p View Post
    Well I can't see all that good so which direction do the strands of bcy 452x twist?
    If you use your fingernail and fray the end, you should be able to see which way it's twisted as you pull the fibers apart.

    But to answer your question... every spool of 452x that I have except for one is twisted clockwise as you look at the end of the strand.

    BCY does make material twisted in both directions for Mathews strings, and the only thing I can figure is that I got a spool that was made for them, or someone forgot to switch the machine back after making a batch for Mathews. So for that reason, I always check a new spool before I start using it.
    Don't worry what people think... They don't do it often.

  13. #13
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    Thanks.

    I never understood the reverse twisting. If you just take a bundle with a clockwise twist and and bundle with a counter clockwise twist and then twist them together clockwise, you will be adding twist to the clockwise bundle and taking twist out of the counter clockwise bundle unless you use a wrapping technique which does not allow any more twist to be put into each bundle.

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