# String Twist?? How many twists? Formula?? Not Sure



## mdharcher (Sep 8, 2006)

I multiply the orginal string length by 1.015 that will give you the lay out lenght for the string.
I then divide the orginal length by 1.6 that will give you close to the number of twists to put into the string to get your length.
59.75 X 1.015 = 60.65 or roughly 60 5/8
59.75 / 1.6 = 37 so 37 twists will be close. Measure the length under 100# of tension to get the correct length


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## animal killer (Sep 16, 2009)

Where do u come up with these numbers? BCY told me to set my jig 1/4 inch longer than the finished string n then twist it up to thr desired length but I was not sure as I've heard ppl do it like stated above n also what I was told


Sent from my iPhone using Tapatalk


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## dwagoner (Sep 27, 2007)

good ratio is 1 twist per 1.5" of string, i wouldnt go much less than that. theres no way you can add 1.5% and only add 37 twist and have it be anywhere finished length. it will be long by quite a bit. 

what material are you gonna use? what poundage do you stretch at?


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## Dthbyhoyt (Dec 4, 2004)

I twist at 1 twist per 1.5" length


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## EGriggs (Mar 11, 2003)

Here is the formula I use for determining twists and the jig setting.

String length (times) 1.0075 (.75%) = Jig Setting
Examples:
40" = 40.3 jig setting
60" = 60.45 jig setting
100" = 100.75 jig setting

String length (divided by) 1.3 = number of twists
Examples:
40" = 31 twists
60" = 46 twists
100" = 77 twists

The key is to find consistent numbers that work for your process. Things that can alter or change this is your layup process, type of material and how you're tensioning/stretching. If you're consistent in your process, you can establish a baseline percentage and work from there. 

Good luck.


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## b0w_bender (Apr 30, 2006)

Hey animal. Using the 1/4" larger method described by BCY gives you different twist ratios depending on the length of the string. Guys that do this for a living want a consistent product so they use the twist per inch method. Having the exact twists is not a performance issue having three or 4 twist difference in either direction is not the end of the world. These number are rule of thumb, you will find some materials stretch more than others and so the original length before twisting will vary to hit your intended twists per inch on the final string. Don't get too wrapped up in the exact twists just make sure you are in that ball park and that your string/cable is the correct length.

I have an Excel file on my website you are welcome to download. It allows you to change your length to twist ratio to meet your own experiences and you can duplicate the workbook to save the data per material that you work with.
http://nwspinner.com/index.php/adjusting-for-twists-and-stretch


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## animal killer (Sep 16, 2009)

Awesome thanks for all the help here guys. What i have been doing is basically measuring my string up 1/4 inch longer than the final string, do my loop serving on the jig, remove and set on the stretcher and insert my strand separators, and then set the tension to 100lbs and what i did last night was took my final string length and divided it by 1.5 and it came out 39.833 twists. I also tried some of the other numbers mentioned and they all came up to about 38-39 twists. So my current string has 39 twists, is spot on for length after i measured 1/4 longer than finshed string, and i stretched my string to 450lbs. I am currently using 8190 material with 3-D Serving. If you thing there might be something i could do to change my process please feel free to help. Ive only built 1 other set so I dont really have a set process down.
Thanks
Phillip


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## animal killer (Sep 16, 2009)

ttt


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## Deer Eliminator (Jan 21, 2010)

1 twist per 1.5 inches of string is what most use. 



Hutch


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## Pappy1 (Apr 18, 2012)

Pat
When you speak of twists is one twist equal to 360 degrees or 280 degrees? I am new to string making and found your videos very helpful.
Thanks,
Pappy


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## Pappy1 (Apr 18, 2012)

Sorry bad typing 180 degrees


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## EPLC (May 21, 2002)

animal killer said:


> I am building a set of strings for my darton DS 3800. I am wondering what is the correct number of twists to put in my string. My string length is 59 3/4 inches. What is the proper way to determine the number of twists for any string or cable?
> Thanks
> Phillip


I have an Excel spreadsheet that you can enter your preferences and it will give you Jig settings and aproximate # of twists. It's free, just PM me with your email and I'll send it to you (or anyone else that wants it)


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## b0w_bender (Apr 30, 2006)

yup 360 degrees. Full rotation


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## jaydub (May 16, 2008)

I wish I knew how to make a spreadsheet that would give me numbers in sixteenths rather then tenths. I know how to do the math, But would be awesome to just punch it in and have it spit it out to match a tape measure......


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## BlindBuck (Feb 7, 2009)

jaydub said:


> I wish I knew how to make a spreadsheet that would give me numbers in sixteenths rather then tenths. I know how to do the math, But would be awesome to just punch it in and have it spit it out to match a tape measure......


I made a spreadsheet based off what a few others have done on here. I added the code below to convert the decimal to fractions and reduce it at the same time. I got tired of converting decimal to fractions, and/or reducing fractions.lol (Note "C9" is the answer in decimal in the formula below)

=IF(MOD(INT(16*(+C9-INT(C9)+0.0312)),16)=0,TEXT(C9,"#"),IF(MOD(INT(16*(+C9-INT(C9)+0.0312)),8)=0,TEXT(C9,"# 0/2"),IF(MOD(INT(16*(+C9-INT(C9)+0.0312)),4)=0,TEXT(C9,"# 0/4"),IF(MOD(INT(16*(+C9-INT(C9)+0.0312)),

Screen Shot


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## ericwhyne (Feb 23, 2011)

Get it close and then check your cam tune. If the string is not the correct length your cams will be off. If a solo-cam your one cam has an alignment indicator, whether it be two pin holes that should be parallel with the string or a hole the cable is visible through.


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