# how many twists too many when increasing brace height?



## ceratops (May 17, 2017)

I'm curious if there's a rule of thumb about this... I have a PSE Intrepid riser, read on a number of threads here that it likes a brace height of about 8 3/4" (with medium limbs), and recently twisted the string to get to that brace height. The bow is less 'twangy' than before, so that's good; but the string looks pretty twisty to me at this point. I think I added about 20 twists (but wasn't really keeping count).

How many twists is too many? And what is the downside (or hazard maybe?) of an overly twisted string?


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## DarkLightStar (Apr 7, 2016)

Depends on the material.

BCY has a recommendation on their site of somewhere between .5 to .75 twists per inch. 

The downside is a string that coils up like a snake immediately after you release and acts more like a spring under tension than a "string." Another downside is that the string will erode quickly and perhaps fray or worse.

If it only took 20 twists to go from a untwisted string to your proper brace height, you are golden and shouldn't sweat it.

Good luck!


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## ceratops (May 17, 2017)

Well, the string already had some twists in it when I started... I will go and look at twists per inch. Thank you for that information!

Related question -- when a stringmaker sells a string at a certain length (actual string length, not AMO length), is that the length with no twists at all? Or is it with some minimum number of twists already included?


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## DarkLightStar (Apr 7, 2016)

Everyone has their own style of making them. Usually what is asked for is an untwisted string in "such and such" a length. 

Different risers and limbs can require different string lengths and it's always good to do a check with the manufacturers if you can. 

As an example, Gillo and MK risers seem to favor a higher brace and I have to assume it is a part of the geometry that the engineer wished to build into the design.

Everyone has their own preference. Too few twists can be noisy and cause the string to parachute upon release, acting more like a brake than a cable.

You're very welcome. Keep at it and you'll find your own style!


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## ceratops (May 17, 2017)

As best I can tell (and it's hard to follow a single strand in a string where all strands are the same color!!), it takes about 1 1/4" for one particular strand to make its way all the way around the string, so I believe that's .8 twists per inch... A bit high compared to the standard you quoted, but not horribly off base, I guess.

Thanks for the info on string measurement. I assume that means, when ordering a specified string length, one should order a bit longer than the final working length on the bow (so the string can be given a few twists)?


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## DarkLightStar (Apr 7, 2016)

I use a formula that seems to work for me and my customers. So much of this will depend on the material used. 8125 is a much thicker material than something like 8190 and so will not like to twist up as much...it'll kink a bit quicker.

Yes, you're a bit high from BCY's recommendations...but that doesn't necessarily mean it's wrong or anything. If you have a quiet bow, and it is tuning well...you're doing great. 

I try to make my strings in the ".67" length so that a customer has a little leeway to tune their bow up and down and find their "sweet spot" in terms of brace. 

If your limb and riser manufacturer has a recommendation on length, I'd start with that. They have plenty of experience and should be trusted to know their own products.

Uukha has an chart on their webpage under tuning that helps an archer see the number of strands recommended for a given weight. I've found it to be an excellent guide.

Just untwist your string completely and then count the number of twists to reach your desired brace. In my case, with a 70" bow, I'd like the number to be around 44 after all my stretching is done and the string is stable.


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## caspian (Jan 13, 2009)

I find around the .65-.75 twists per inch mark to be a good combination of keeping the string nicely bundled, providing a little shock absorption, providing enough helix that a couple of twists plus or minus actually does something, and not being a knotted up pest to handle off the bow.



ceratops said:


> Related question -- when a stringmaker sells a string at a certain length (actual string length, not AMO length), is that the length with no twists at all? Or is it with some minimum number of twists already included?


string length is finished, i.e. twisted length. part of the art of string making is gauging the loss of length from layup to finished length caused by the twists, plus other factors such as material stretch. I typically put a "barebones" 30 twists into a string when finishing it to make it easy for initial handling, with the intention that the archer will twist up to desired brace height. the helix factor shortening that induces conveniently matches the material stretch I get during the build process.

if you want a number of twists in a string that diverges from a typical sort of range, talk to your string maker.


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## nickle (Sep 25, 2017)

to clarify, the .7 is the number of twists per inch of bow length. .7 x 70 =49 total twists


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## ceratops (May 17, 2017)

nickle said:


> to clarify, the .7 is the number of twists per inch of bow length. .7 x 70 =49 total twists


Really? That would be annoyingly confusing if true 

Admittedly, standards are sometimes defined in confusing ways...

Why on earth would they count string twists with respect to something other than the string itself, though...?


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## Viper1 (Aug 21, 2003)

c - 

I like my strings to have as few twists as possible (not zero, but few), and build them that way. If the loose string starts kinking up due to the number of twists, you've gone too far. Keep It Simple Stupid. 

Viper1 out.


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## DarkLightStar (Apr 7, 2016)

Viper,

I respectfully disagree with your string building philosophy as you've stated above. Certainly not with the "kinking up" part, but nearly zero twists? That seems to fly in the face of conventional wisdom and I haven't seen an Olympian's bow that has ever been like that.

But, that's a very cool thing about archery. We all have different things we feel are good.


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## Viper1 (Aug 21, 2003)

Dark -

May I suggest an experiment (assuming you know how to make a string)?

Make two, one with about a 1/2 dozen twists (any direction) and one with as many twists as you can get before kinking. Both have the same construction and yield the same brace height. Let both "settle" and let me know which one gives statistically better scores. 

I've (inadvertently) been in that position, and am willing to bet 99% of people who responded haven't and are basing their theories on hearsay. 

Let's be real, you need very few twists to prevent ballooning and while I wouldn't shoot with a string bordering on kinking for any length of time, there's a pretty big gap between the too where things like that that just don't matter. 

And one last thing, that I think I've said before:



> But, that's a very cool thing about archery. We all have different things we feel are good.


Yes, it is very cool, and when people have diametrically opposing theories and both have been successfully employed, on only conclusion is that the differences just don't matter.  I think if more people understood that, we have happier and overall better shooters. 

Viper1 out.


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## DarkLightStar (Apr 7, 2016)

I agree and I'm quite willing to try your theory out. Thank you!


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## caspian (Jan 13, 2009)

building strings using a compound style method and removing the permanent creep component of the string (far beyond what will ever be experienced on the bow) allows the string to be built with very close to the number of twists required for final use.

the first 20 twists in a string does very little to tensioned length, if you have a largely "straight" string and need to adjust BH up a little then you're going to be twisting it up a lot anyway. if you need to lower BH... oops, you can't.

I see no point in running exceptionally low twists, and I'm pretty sure that if it was any sort of advantage, we'd see top level competitors doing so. we don't, so QED.


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## ceratops (May 17, 2017)

Related question - about how much change in length can you get, between a string with just a few twists to keep the strands together, and the same string with maximum acceptable twists?


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## DarkLightStar (Apr 7, 2016)

Maybe 1/2". That's a little hard to answer scientifically because "acceptable" is relative. Also, different materials twist up at different rates. Also, the number of strands used affects the initial length and stretch of the string.

Lots of little variables to consider in this pretty innocent question.


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## ceratops (May 17, 2017)

Thanks! I was just looking for a ballpark number.


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## whiz-Oz (Jul 19, 2007)

DarkLightStar said:


> I haven't seen an Olympian's bow that has ever been like that.


I have. 
Australian 2008 Olympian Michael Naray's Gigastring had absolutely no twists and I confirmed it with him at the time. 
It had wax on it that was so finely finished it looked like the gigastring strands were encased in perspex rod.


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## DarkLightStar (Apr 7, 2016)

That's great! I still wouldn't make a string like that.


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## lees (Feb 10, 2017)

Viper1 said:


> Dark -
> 
> May I suggest an experiment (assuming you know how to make a string)?
> 
> Make two, one with about a 1/2 dozen twists (any direction) and one with as many twists as you can get before kinking. Both have the same construction and yield the same brace height. Let both "settle" and let me know which one gives statistically better scores.


Not meaning to jump in, but I've actually done this by accident when I was first learning to build. I did the layup on a string too short once, due to an error in my 6th grade education, and once I got it on the stretcher it only took literally about 15 turns to get it to finished length (approx. 67" at 100lbs). I went ahead and finished it and put it on the bow, figuring what the heck let's try it out. 

I have to say, it worked very well with absolutely zero creep. I can't hit the target with a recurve no matter what's on it so I have no way of gauging how it would affect scores, but it was one of the best strings in terms of durability and stability I ever made for a recurve. I think I still have it in the bow case somewhere.....

So just another anecdotal data point that may or may not indicate anything....

For compound cables I've never tried a very low twist rate so I don't know what the effect would be....

lee.


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## DarkLightStar (Apr 7, 2016)

You know, I really respect you guys for sharing your viewpoints. I learn a lot every day. 

The objective of twisting a string up and down is to get this bundle of mass to work as one unit. If you have material that exhibits low to no creep, I can see how something like this would be great.

If you're not completely sure of your brace height or use a material that hasn't been properly stretched, well, you're looking at disaster.

So, sure! Experimentation is a great thing. It's good to be in the company of folks who seem to have a handle on this type of design. 

If the scores reflect the concept and execution, it's probably a step in the right direction.

That being said, why do you think many manufacturers are not recommending such an approach?


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## lees (Feb 10, 2017)

Just so you know I'm not advocating it - just found it to be true on just this one accident string.... Otherwise, I mostly come from the compound world as far as string making goes and there a consistent twist rate of 1 to maybe 1 1/2" seems to be the standard. I memorize the post settings on the strings I make for my bows so the twist rate is always the same from set to set, but I don;t have a good QC on maintaining a particular twist rate across everything I make. Which I definitely would implement if I made strings for people's hard earned money, tho.

If I had the time and a candidate compound bow to use for it, I'd experiment with a low twist rate, though, just to see what would happen. I'm too chicken to try it on the bows I currently shoot because I only just now got em all shooting right and don't want to mess em all up again... 

lee.


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## ceratops (May 17, 2017)

OK, I have a practical question, related to the conversation in this thread. I recently acquired a warfed 17" riser, and am putting medium ilf recurve limbs on it, for 60" amo bow length. As best I can tell, measuring along the belly of bow, it is actually very close to 60" (maybe 60 1/4", but there always seems to be some uncertainty about where exactly to measure along the riser...).

So, I was pleased to remember that we have an old ugly Indian Archery bow hanging around - something my husband uses once a year or so to get a rope up into a tree, otherwise unused, and too heavy for me to shoot in any case... Sure enough, the IA bow says 60" on its label, and I figure I can temporarily borrow its string for my new bow, and maybe do some tuning for best brace height. Unfortunately, when I put this string (from a 60" bow) onto my new (also 60" bow), it ended up with a pretty ridiculous looking 9 1/2" brace height. That mystery was somewhat resolved when I measured the IA bow, which appears to be only about 59" long. Argghhh.

Coming at long last to my questions -

The strung bow has 9 1/2" brace height, and measuring straight along the string I get 55" from one limb-tip string groove to the other. Can anyone hazard a guess how much I should add to that 55", in order to bring brace height down to 7 1/4" - 7 1/2"? It seems that would be a good starting point for a 60" recurve; but with a modified riser like this, I can't exactly look up recommended brace height on a manufacturer's website.

As Caspian noted in one of the posts above, the first few string twists, going up from a totally untwisted string, don't seem to do squat - I took about 15 twists out of the string, trying to get lower than that initial 9 1/2" measurement, got down to practically no twists, and observed virtually no reduction in brace height.


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## ceratops (May 17, 2017)

And another question - at least some sites (e.g. 60xbowstrings) say they measure their strings under significant tension, and therefore you need to add an inch or so to your measurements when ordering a string from them. Really? So if I need, for example, 57" between limb tips, I would have to order a 58" string? Is this a common convention among string makers? Or do most give finished length at rest rather than under tension?


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## caspian (Jan 13, 2009)

the AMO standard for measuring string length is on page 4 of this document: http://www.outlab.it/doc/amostd.pdf measurement tension is theoretically a function of draw weight, but I just use 100lb for everything.

bear in mind that's just a standardised means of measurement though - no oly recurve is ever going to see such a weight in practice.

conventional wisdom was that a recurve string is 3" shorter than nominal bow length, but many/most modern bows have a recommended brace brace height higher than that would produce, so shorter is becoming quite normal. this page has some guidance: https://www.ocf.berkeley.edu/~archery/wp-content/uploads/docs/bowstring-dimensions.pdf


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## ceratops (May 17, 2017)

Thanks for the useful references! So, to make sure I understand this, ordering a string by 'conventional wisdom' would lead me to order, say, 57" (assuming the bow measures 60"). However, that 57" string was actually measured under 100 lbs of tension, so, on the bow, it would only measure perhaps 56" or so straight between the limb tip attachment points (because the bow isn't putting anything like 100 lbs of tension on the string, and also because the limb tips are actually wider than the 1/4" pins specified in the document you linked)? Do I have it right now?


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## stick monkey (Mar 9, 2015)

I just wanted to add here that there was a video somewhere of Brady Ellison saying that he likes a lot of twist in his strings...he said for him that his strings have around 75 twists... claiming that it makes his strings more round... how can you argue with anything Brady says or does...or maybe he's just doing it wrong?


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## caspian (Jan 13, 2009)

I think most people would find it hard to argue that Brady is doing anything wrong. however, that doesn't mean it's the best solution for someone else, or the only way of going about it.



ceratops said:


> Thanks for the useful references! So, to make sure I understand this, ordering a string by 'conventional wisdom' would lead me to order, say, 57" (assuming the bow measures 60"). However, that 57" string was actually measured under 100 lbs of tension, so, on the bow, it would only measure perhaps 56" or so straight between the limb tip attachment points (because the bow isn't putting anything like 100 lbs of tension on the string, and also because the limb tips are actually wider than the 1/4" pins specified in the document you linked)? Do I have it right now?


yes, correct. I don't find untensioned length to be a particularly useful measure, especially when different people use different rates of twist. it's only of any particular interest if you are building a string, and even then I would untwist the string to determine the initial layup length. or I'd just tension and measure the twisted string, and make allowance for factors like twist and material stretch and creep.


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## lcaillo (Jan 5, 2014)

One thing to note is that as you get to large numbers of twists the effect on brace height of each twist gets greater. I cannot tell any difference in performance but it matters more when you lose a few twists if you are picky about the brace height. 

Sent from my SM-G950U using Tapatalk


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## Roy D (Nov 30, 2019)

DarkLightStar said:


> Too few twists can be noisy and cause the string to parachute upon release, acting more like a brake than a cable.


Interrupting on an old thread but curious - I have been tweaking BH on my new bow and the string that came with was far too long and would have taken 50+ twists likely to achieve proper BH per manufacturer spec.. Got another fitted and that one proved too long still but it is getting there with steady twisting.
In my mind I wás thinking by the time the string is stretched out and BH is stable and to my liking I could then when it is time for a new one measure and get one that is much nearer the proper length for the BH intended but if I read this correctly a string wíth more twist would behave better than one without?
And am guessing here but with more twists it is likely to need replacing sooner though no?


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## stevelong (Jan 13, 2010)

Katrin, you might have solved all your thoughts & questions by now, but your theoretical new 56" actual length string stretched by 100 pounds of force by stringmaker to 57" actual length does not necessarily relax back to your first 56" actual length after 100 pounds is removed. The putting 100 pounds of load on the string takes all the looseness and play from the string, making it a nice respectably solid unit ready for work. Order what you need, and in this case my old 17" riser with ILF medium limbs will take about a 57" actual length string. I used strings that came off my 17" DAS riser & medium limbs.


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## regas (Oct 24, 2013)

I would like to see a video of the ballooning or parachuting effect of an untwisted string on a bow. it sounds like an urban legend to me.


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## ceratops (May 17, 2017)

stevelong said:


> Katrin, you might have solved all your thoughts & questions by now, but your theoretical new 56" actual length string stretched by 100 pounds of force by stringmaker to 57" actual length does not necessarily relax back to your first 56" actual length after 100 pounds is removed. The putting 100 pounds of load on the string takes all the looseness and play from the string, making it a nice respectably solid unit ready for work. Order what you need, and in this case my old 17" riser with ILF medium limbs will take about a 57" actual length string. I used strings that came off my 17" DAS riser & medium limbs.


Makes sense, as you say, that stretched string does not go all the way back down to prestretched length when tension is taken off.

Yeah... After all the good info shared in this thread, I was still not 100% certain that those stringmakers who sell by actual length were all even using the same criteria. So I bailed, and just threw a '60" AMO' generic string into my next LAS order. It fit fine, gave reasonable looking brace height, and the bow is nice and quiet to shoot. Just measured, and actual length of the string on the bow, all the way to end loops, is 57 1/4"

Hey, were you trying to move that little riser on to a possible new owner?  Got a pm with a polite inquiry whether I owned such a riser, replied that this is currently one of my favorite bows, and haven't heard a follow-up question since...


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## ceratops (May 17, 2017)

Roy D said:


> Interrupting on an old thread but curious - I have been tweaking BH on my new bow and the string that came with was far too long and would have taken 50+ twists likely to achieve proper BH per manufacturer spec.. Got another fitted and that one proved too long still but it is getting there with steady twisting.
> In my mind I wás thinking by the time the string is stretched out and BH is stable and to my liking I could then when it is time for a new one measure and get one that is much nearer the proper length for the BH intended but if I read this correctly a string wíth more twist would behave better than one without?
> And am guessing here but with more twists it is likely to need replacing sooner though no?


My conclusion from all the replies in this thread were:

1) straight end-to-end length on the bow, once you have the brace height correct, is indeed a useful thing to know

2) if you then want to order a string to length, an actual communication with the string maker is probably best - e.g. "I want a string of X length on my bow, assuming Y number of twists" 

I haven't actually done step 2 yet when buying a string, but it seems the only sensible way to really cut out the uncertainty. Similarly, for proper nock fit on center serving, actual communication would be sensible.


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## stevelong (Jan 13, 2010)

ceratops said:


> Hey, were you trying to move that little riser on to a possible new owner?  Got a pm with a polite inquiry whether I owned such a riser, replied that this is currently one of my favorite bows, and haven't heard a follow-up question since...


nope......I sent you a pm with 'splains.


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## Stash (Jun 1, 2002)

I'm not seeing much reference here to the actual string material being used, and method of string construction, and it makes a difference.

Basically you have "creep" and "stretch" to consider among different string materials. Creep is a continual elongation of the string as it's under tension. Stretch is like elasticity - the string gets longer under tension and contracts when the tension is removed.

Some materials have a lot of each, like Dacron (polyester). Some have almost none of each, some have almost none of one and some of the other.

So, you could end up with a string that will continue to creep and needs to have a few twists put in as it gets older. You could end up with a string that needs to be stretched out a bit each time before you start shooting, and you have to add a few twists as the day goes on.

The number of strands is also important. A 10 strand dacron will stretch and stretch and stretch. A 16 strand dacron, not so much.

The quality of construction also is a concern. A poorly made string may have strands that are of uneven tension, so it may stretch a bit more than expected because only a portion of the strands are taking up the tension. A sloppily made Flemish string may take quite a while for the loops to compress, and may seem to elongate until they settle down.

Lots of variables to consider. No one answer as to the "right" number of twists, though. Should have maybe 15-20 at a minimum, not because of this mysterious "ballooning", but mainly to keep the strands together so random strands are not hanging out where they can get snagged or damaged. A maximum would be if you take the string off and it curls up like a scared snake.


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## Roy D (Nov 30, 2019)

Yes - I understand a little more about that now Stash 
I believe someone mentioned this article in another thread recently also but this explained a lot for me. The tip about stringing it untwisted overnight before tweaking the BH seemed especially useful.

The most general note on twists in that article: 
_more twists will slow the bow slightly and potentially produce much less noise, while fewer twists will add a tiny bit of speed, but potentially more noise and vibration after the shot._

Twisted strands will rub each other uncoiling a little after having coiled at full draw expending energy ( slowing ) and since they are twisted around each other they do not slap each other so much or when they do that slapping vibration is directed at all angles more diffusely into itself than with a less or untwisted string hence the more silent shot ..I think


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## lksseven (Mar 21, 2010)

Roy D said:


> Yes - I understand a little more about that now Stash
> I believe someone mentioned this article in another thread recently also but this explained a lot for me. The tip about stringing it untwisted overnight before tweaking the BH seemed especially useful.
> 
> The most general note on twists in that article:
> ...


Adding twists or reducing twists can both add noise, if one or the other action is making the arrow nock work harder coming off the string. It's situational from one scenario/setup to another. 

Adding twists to the bow slows the arrow because the arrow is on the string a shorter distance (if strands rubbing against one another is a real thing, it's surely not applicable to all but a handful of elite archers) and thus misses out on the last amount of limb power thrust/string travel (1/4", 1/2", 1" ???). And it can be a significant amount of speed lost or gained, not just "slightly", depending on how much brace height is added or subtracted.


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## Roy D (Nov 30, 2019)

Non native English speaker here so intended meanings may go by me sometimes ^^ but I understood Eastons article such that they were referring to same bh achieved with either untwisted or (much) twisted strings - the noise difference and speed difference actually causal from the geometry of the string's strands ? 

Noise wise probably related to the same physics as with string instruments - denser ( same string lengths but one made from wound longer length is denser than same string length made from unwound) just sound different and some frequencies are perceived louder and more or less pleasant than others. Energy also travels at different speeds in different densities. 
And the limbs can be seen as a soundboard of sorts - besides themselves already vibrating violently ^^

Sorry if my sentences are a mess 
And sorry if my thinking is way off on a tangent lol


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## Roy D (Nov 30, 2019)

And now to complete the derail of the thread lol.. 

Some studies I found relating to fiber strength with many different types of material out there - breaking strength decreases with increasing twist as a more shearing load is introduced and warming effects of friction under loading/unloading cycles. Twisting like this is used in mooring ropes - the tightening and loosening of the coiled fibers under load reduces shocks but they don't last because of all the wear from the friction internally and reduced load capacity. Reminds me of that rubber band test - put a non strung rubber band between your lips feel the temperature now let it be for a bit then really stretch it a few times and feel again - warmed up noticeably. So adding twist will slow the speed of the bow's string because it introduces friction in the string structure but if the string is short enough to achieve optimum BH speed wise and you do not mind replacing strings more often lots of twist might feel nicer by from what I have read helping dampen vibration of the limbs a little more than an untwisted string. Have seen videos that the arrow's fletchings have yet to clear the riser when the limbs are starting to move backwards again after having loosed - torqueing the riser and bow putting shock into the bow arm and it continues to do so for quite some time and the string is instrumental at stopping this - the stiffer it is the more quickly it dampens this motion as it disrupts the wave in them.

All such cool stuff ^^


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## camperjim (Oct 22, 2016)

I make my own strings and have since I began with archery so I have never needed to experiment with a large number of twists. I have made plenty of strings that were a bit too short or were just the right length without any twists. They seem to work well with no issues. I do prefer strings with 10-20 twists. If nothing else that holds the strands together and makes it less likely to snag the string walking in the woods or just due to carelessness.


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## Roy D (Nov 30, 2019)

Hi Jim yes working well enough is good enough for me. This supertwisting of the string who does it and the why of it its all the cutting bleeding edge of performance. Either that or the equivalent of rubbing a rabbit's foot lol. 
At our club it is all volunteers, tight budget. Saving up for a new floor in it. Bet someone has to make string for all the club bows every now and then. 
Might be a good skill to pick up for me help out and try some things without breaking the bank. Or a string ^^


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