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    Some questions about strings

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    ZigiMan
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    Some questions about strings

    Post by ZigiMan on Tue Mar 05, 2013 4:16 am

    Well, after not getting too much answers about my questions about the string in my main topic (maybe the pictures took all the attention Very Happy) I've decided to to post a separate topic.

    I have some questions regarding strings that I couldn't find reliable
    answers to them. You folks probably will have good answers...

    1) As I know, waxing the string is recommended but except from slipping the sting, does it has more benefits?

    2) Does using a wax is a most or can I skip it?

    3) The common wax material I read of is bee wax (correct me if I'm wrong)
    but I could find any in here. What are other waxing materials can be a
    substitute to bee wax?

    4) Is there any important things I should know when using linen as string material?

    5) What is the recommended strength of string in ratio to the draw
    weight? I saw somewhere says 4 times stronger and in other place 8
    times...)

    ZigiMan
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    Geezer
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    Re: Some questions about strings

    Post by Geezer on Tue Mar 05, 2013 6:46 am

    Some string answers: waxing your bowstring is a good idea, it will make it last longer, more water-resistant, less likely to get fuzzy with use (fuzz will slow your string, decrease accuracy, probably shorten string-life)
    You can use an ordinary paraffin candle for waxing, but bee's wax seems to have been preferred in the middle-ages. A check online with archery suppliers should provide cakes of bee's wax. Failing that, I'll wager you can find it from weaver's supply shops.
    I have made bowstrings from linen: it's substantially stronger than hemp, so you should be able to make lighter bowstrings, but linen doesn't stretch much, and it soaks up water like a sponge... so it would be particularly wise to wax your linen strands before assembling a string.
    Also, since linen (flax) is very hydro-phillic, it pulls the moisture out of your hands. Either use gloves, or plenty of moisturizer when working with flax. Otherwise, you'll get very dry skin with lots of string-cuts. I hate string-cuts... like burns they persist for days!
    Note since linen is non-stretchy, you can't afford to twist the string much to fit on your prod. This is particularly the case with thicker strings. Too much twisting guarantees breaking one or more outer strands... then the whole thing goes... zip!
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    ZigiMan
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    Re: Some questions about strings

    Post by ZigiMan on Thu Mar 07, 2013 2:52 am

    Thanks for the answers Geezer! You are a fountain of knowledge!

    ZigiMan

    p.s. If anyone else want to share his opinion - still wondering of the ratio between the prod and string strength...

    chaz
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    Re: Some questions about strings

    Post by chaz on Thu Mar 07, 2013 5:36 am

    Zigi,

    Another question about string : How to determine the length ? What rule of thumb should be used for the length in relation to the distance between the nocks on the prod ? An inch ... inch and a half shorter ...... what ? Or just enough to put tension on the prod ?

    Chaz

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    Re: Some questions about strings

    Post by panne on Thu Mar 07, 2013 6:07 am

    you can find 1 pound cakes of beeswax in the candle making department of hobby lobby and other craft stores like michael's. i prefer beeswax over other waxes because it stays fairly soft and sticky. most of the candle waxes i've tried get brittle and crumble. if all you can find is a brittle wax, you can melt it and add a few drops of oil until you get the consistency that works for you.

    i've used #6 prewaxed linen when i didn't have dacron. you can find it at electrical supply sites online. it was at one time used mostly for lashing bundles of cables together, before zip ties.
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    Re: Some questions about strings

    Post by stoneagebowyer on Thu Mar 07, 2013 2:33 pm

    ZigiMan, the rule of thumb for a hand held bow is 4/1. I.e. the string should be four times the weight of the bow. If you have a 60 lb. bow, you want a string at least 240 lbs. breaking strength. I have heard also different ratios for crossbows, such as 8/1 and 10/1.
    I think erring on the side of caution is not a bad idea. That last crossbow I finished has a 160 lb. prod, and I made the string with 50 strands of B50, which has an appox. breaking strenght of 50 lbs. That means the string has a breaking point of 2,500 lbs!
    Do also remember that at the nocks, if you make a typical endless loop string, you have to divide that number in half. But even there, my string has a breaking strenght of 1,250 lbs.
    Pure bees wax may be okay, but I'd recommend you getting string makers wax. Archery suppliers sell it. It is a combination of bees wax and pine rosin. Another option is cordwainer's coode, which is bees wax and gum rosin, which may be the same as pine rosin, but not totally sure.
    Dane

    ZigiMan wrote:Thanks for the answers Geezer! You are a fountain of knowledge!

    ZigiMan

    p.s. If anyone else want to share his opinion - still wondering of the ratio between the prod and string strength...
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    Re: Some questions about strings

    Post by ZigiMan on Fri Mar 08, 2013 2:02 am

    chaz wrote:Zigi,

    Another question about string : How to determine the length ? What rule of thumb should be used for the length in relation to the distance between the nocks on the prod ? An inch ... inch and a half shorter ...... what ? Or just enough to put tension on the prod ?

    Chaz

    That's also a good one, Chaz... Experiment gave me my answer - I've made a 3cm (1 6/32 inch [it's seems that the inches measurements will always be strange and not efficient to me Smile]) shorter string, only to find out that the wide nocks I've made for my prod made it 1 cm (13/32 inch) shorter. Bracing it was hard and high. I've made another one or two a little bit shorter which wasn't suitable for me. The third or fourth and final one was the same length but the nocks made it 1 cm shorter. This one seems right - very tense, not too hard to brace and not to high.

    Panne. unfortunately we don't have the variety of materials you have in the hobby stores. Ordinary candle wax was the only one those stores has. But Nerd Flintsone told me I can find bee wax in orthodox Christian churches so I'll give it a try.

    Dane, With that weight you can pool a truck! you make a good point regarding the nocks, I didn't take that into consideration... Four times will be a good start, I'll see how it acts.
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    kenh
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    Re: Some questions about strings

    Post by kenh on Fri Mar 08, 2013 5:41 am

    Zigi-man. You might be able to make something like the wax/pine rosin mixture that StoneAge mentions. You may be able to find pine pitch or rosin there. Or rosin from a violin shop and melt the two together. Or check around some of the open markets like the Shuk Carmel; maybe a spice dealer or someone like like would have pine rosin...
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    Re: Some questions about strings

    Post by Hotspur on Fri Mar 08, 2013 9:07 am

    chaz wrote:Zigi,

    Another question about string : How to determine the length ? What rule of thumb should be used for the length in relation to the distance between the nocks on the prod ? An inch ... inch and a half shorter ...... what ? Or just enough to put tension on the prod ?

    Chaz


    A couple things I have gleaned off this site regarding brace hight:

    You want the brace height to be high enough to clear the table but not too high, or you will lose power and it will be difficult to string.

    The brace height should be about 1/8th the nock to nock length of the bow.
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    Re: Some questions about strings

    Post by stoneagebowyer on Sat Mar 09, 2013 4:32 am

    Hotspur is right. I build a crossbow last year that had string height a bit too high. It shot safely, but the bolt began tumbling erratically at around 10 yards or so, so accuracy was not good. Once I removed the prod, modified the back of the prod socket to bring the string down to the table / top surface of the crossbow (about 1/8" was all), it became a very accurate shooter.
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    Re: Some questions about strings

    Post by Gnome on Sat Mar 09, 2013 8:58 am

    stoneagebowyer wrote:Hotspur is right. I build a crossbow last year that had string height a bit too high.
    Was that your "pugnacious" build? I liked that one quite a bit and was curious how handy it turned out to be in the long run. I was building one at the time where I experimented with higher brace height but haven't had much luck getting it out to a range regularly to put it through it's paces.
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    ZigiMan
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    Re: Some questions about strings

    Post by ZigiMan on Tue Mar 12, 2013 3:40 am

    kenh, glade to know that you are familiar with my little country Very Happy I don't think that the merchants at the market will have it. There are more chances that I will find it in a guitar shop.

    Meanwhile, I followed Nerd Flintstone's advice and went to a Greek orthodox church and found some ceremonial candles from bee wax.

    I will keep in mind the advices of mixing wax and rosin. I probably use it in the future and compare it to bee wax.

    My prod's brace height is 11 cm (4 11/32 inch) and when I span, it reaches about 31cm (27 18/32inch). It seems like the angle, 5 degree, I temporarily installed to test my prod is a little bit low. The string seems to be in a lot of pressure over the stock while it is not spanned.


    Last edited by ZigiMan on Tue Mar 12, 2013 3:49 am; edited 1 time in total (Reason for editing : spelling)

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