# changing brace height by twisting string



## rambo-yambo (Aug 12, 2008)

I bought a new bow (Samick Agulla) with 12 strand dacron string; I tried to increase the brace height by twisting the string. I twisted the string ten turns but brace height did not change; instead I got a high pitch "dang" from my string and the string vibrated like a guitar string. 

I have done similar thing on another bow with a different string, and the brace hieght increases as I increase the number of twist. 

Is this a phenomenum with the bow or the string? Any help would be appreciated.


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## Xcreekarchery1 (Aug 7, 2007)

what happend is the string probably stretched between measuring and twisting the string. i dont have any experience with darcon but i know some strings will stretch alot, just play around with the brace height and youl find the quietist and best grouping point. 

Chris


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## Progen (Mar 17, 2006)

Where did the string come from? Did you twist it 10 turns from its untwisted point? And when you said 'high pitched', how high was the pitch?  Strings under tension do sound very much like guitar strings although I'd liken them more to bass guitar ones.


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## Viper1 (Aug 21, 2003)

RY -

10 twists on an *untwisted* string "might" not make a noticeable change, while 10 twists in a *heavily twisted* string "might".

Viper1 out.


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## rambo-yambo (Aug 12, 2008)

The string comes with the bow (Samick Agull) when I bought it as apckage from Alternative Sports. 

I am not sure if the original condition of the string was twisted or untwisted but the brace height was less than 7" (Samick Agull with short limbs). The brace height of that bow setup (Samick Agull with short limbs)should be around 8-1/2" to 9" so I twisted the string ten turns - the brace height did not change except for the noise. I guess the noise is more like a lower pitch like a bass guitar. I can actually see the string vibrates (similar to striking a tight rubber band) and it resonates for a while. 

I tried using a flemished string that I have on this bow and it did not make the same noise; the bow was noisy but the string did not make noise. I think the noise came from the bow ibecause it was not exactly tuned. 

My theory is that the 12 strand endless loop dacron string stretches when twisted so the brace height does not change except the string is now under a lot of tension. I need to have someone to confirm my theory. Looking forward to learn some more from you all.


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## scriv (Jan 31, 2008)

*twists*

Running up the brace height 1.5 ti 2 inches is going to take alot of twists. Specially at first. When I make strings I use a cordless drill to put some twists in it. That much adjustment may require a shorter string. (Which is how I got started making them in the first place)


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## Progen (Mar 17, 2006)

Viper1 said:


> RY -
> 
> 10 twists on an *untwisted* string "might" not make a noticeable change, while 10 twists in a *heavily twisted* string "might".
> 
> Viper1 out.


Yeah, but he's talking about dacron. I was about to make the same remark as yourself until I started thinking and doing some research on dacron. I've used dacron quite a bit but never on my own bows. Lowest I've gone is FastFlight.

Rambo-Yambo, you might have been given a string for a 68" bow which would be meant for medium limbs with your riser. Added with the stretchiness of dacron, you'd be needing a LOT of twists to get to the recommended brace height in which case I think it's best you contact the Alternative people for a more appropriate string. Be nice to them and I'm sure they'll send you one at no extra charge.

ps. If you're going serious with archery and planning to do some outdoor shooting, perhaps you might want to consider an upgrade to at least FastFlight.


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## Greg Bouras (Nov 17, 2006)

It is not difficult to measure the change in length of the string as twists are added, 10 twists on a non twisted string is not very much and depending on initial length at initial twists may yield nothing. You may want to check this for yourself with a nail and tape measure if you have not played around with it.

Insure that you are adding twists in the direction the string was original twisted otherwise as in Planes, Trains and Automobiles you are going the wrong way.

That may actually be what is happening. As twists are removed from string any loose strands will vibrate at a different frequency than a taught one.

Broken strands especially under the center serving can be discovered this way.
Sounds like an e-clip on a compound axle rattling when plucking.


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## cc46 (Jan 22, 2005)

new strings will stretch, or settle ..so expect to twist it for a few sessions, then to change brace height about ten twists for a 1/4". Also I think I remember reading max 1.5 twists per inch of length---that means about 80-90 twists for a recurve string


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## Progen (Mar 17, 2006)

cc46 said:


> ... that means about 80-90 twists for a recurve string


I think 80 - 90 twists is overdoing it quite a bit.


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## Archer-8 (Jun 24, 2009)

I would think a Aguilla bow with short limbs would take a brace height of about 8 3/8".


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## Lindy (Nov 7, 2008)

*Brace Height and String Twist*

I recieved this email from Sharon Rose, V.P. at Brownell this morning.

"We (i.e. Brownell) recommend 1 turn per 3 inches 90 inch string divided by 3 is 30 turns.

Sharon"

Brownell recommends that you keep these as a maximum amount of twists. If more are needed consider making a shorter string.

I made a new string three days ago and the brace height was 8-1/2". I added 10 twists and the brace height changed from 8-1/2" to 8-3/4".

I am shooting a 68" Win & Win bow, 16 strand Bownell TS-1 string.


Regards and Good Shooting


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## rambo-yambo (Aug 12, 2008)

Progen said:


> ps. If you're going serious with archery and planning to do some outdoor shooting, perhaps you might want to consider an upgrade to at least FastFlight.


What is your recommendation on string? What do you know about bcy 8125 string? 

I put on a string from another bow on this new bow, now the brace height is now about 8.25". I measured the lengths (same at about 62.5") and diameters of all the strings I have; the Cartel Dacron string that comes with the bow measured 0.075" while other strings measured 0.088". 

Since strength of a string is directly proportional to diameter for same material, a reduction in diameter equals to a reduction of tensile strength and an increase of elongation. A 14% reduction in diameter equals to approx 21%reduction in area. I think a 12 strand string is fine for a light weight bow but it might not be sufficient if the bow weight increases. :mg:

What do you think? :embara:


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## Progen (Mar 17, 2006)

Rambo-yambo, there's a Chinese saying which transliterates to 'Ni xiang tai duo'. Direct translation would be 'You think too much'.  Means, you're worrying unncessarily.

That reduction in tensile strength is of no consequence since theoretically, 1 strand alone has a tensile strength greater than the poundage of your bow. That's assuming you're somewhere in the upper 20s or lower 30s now.

I've only used 8125 once and that was 4 years ago. Chose it because I wanted a multicoloured string and the Angel ASB Dyneema only came in white. It was alright (to me) and it's still a material many top shooters use so you can't go wrong there.


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## rambo-yambo (Aug 12, 2008)

ThanK you Progen for your comment.

I do notice one thin about this string that is kind of unusual(compare to my other strings. There seems to be no twisting of the string in it free state. Should the string still be twisted? What holds the twisting together? I don't know a lot about string may be someone can answer this question. Thanks.


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## Progen (Mar 17, 2006)

Free state meaning when it's not strung up on the limb tips? If it untwists itself, that could mean your string's very dry. A nicely waxed string shouldn't untwist itself even when removed.


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## Steve N (Apr 27, 2004)

As Progen says, a waxed string should not untwist so you can see individual strands when off the bow. Make sure your string is waxed, then twist it up enough to get the desired brace height. You can twist the string as much as needed until it starts to get hockles in it (where the string actually starts to twist back on itself, forming a bump, or knot.) When you remove a twisted string from your bow, if you hold the ends together, then fold it up, it should not untwist. Always check your brace height when restringing your bow.

If you shoot a string with no, or only a couple of turns of twist, the individual strands will balloon out, increasing drag, and decreasing arrow speed.


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## rambo-yambo (Aug 12, 2008)

Do you twist the string before waxing or wax the string before twisting or does it matter? Thanks.


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## Steve N (Apr 27, 2004)

Doesn't matter. You will need to re-wax your twisted string periodically, and that is done with the string twisted. Wax whenever you see the fibers start to show fuzz. Don't go too long between waxing. You don't want to untwist, wax, then twist up again, thats just a bunch of wasted time and energy.


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## Progen (Mar 17, 2006)

Just make sure you get the wax in nice and good. Literature suggests using a piece of leather. I actually use the leather face of my fingertab for this very purpose since it serves an extra purpose of keeping the leather supple.  Then again, those of you who play the guitar, especially the electric bass, should have finger pads tough enough for the job.


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