Primitive Archer
Main Discussion Area => Bows => Topic started by: DC on February 03, 2015, 02:21:04 pm
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I'm trying to move the string to the left. Following this "Mechanics of limb twisting" thread http://www.primitivearcher.com/smf/index.php/topic,27206.msg364231.html#msg364231
I scraped the belly in the area marked (poorly) in red. It didn't do much and may have made it worse. Did I scrape in the right spot? Should I bend a limb? Which one?
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Sorry. I just took another look at it unbraced and the alignment is out then too. I will bend a limb. "Look twice scrape once" or something similar :-[ :-[ :-[
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Scraping one side of a limb works for prop twist. If you have string alignment issues, you need to heat correct the limbs. Remember, the string only has to align between the nocks and thru the center of the grip... what happens between those 3 points is open. You can also manipulate string alignment with the nocks if you've left yourself extra width to do so. Also keeping in mind... if you've scraped both limbs unevenly on the same side, you'll get twist in the same direction, giving you string misalignment. The limb will twist towards the weak side, where you've removed too much wood. Solution... make sure you're removing wood evenly throughout the tillering process. Most people will tend to pull towards their strong hand while scraping. Be aware, and check often that you're removing wood and keeping the belly flat (for a flatbow).
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I would ask if you have JUST an alignment issue, or the limb is twisting from dead flat when unstrung to twisted when strung or drawn. If it's the former then the prescription for me would be different than the latter.
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A little dry heat sorted it out. I was confusing the problem. I thought it was twisting as it was being braced/drawn but as it turned out it was just alignment. Petty sure my head is straight now. Thanks
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Glad you got it sorted. Prop twist and string alignment are usually separate issues, with different solutions.
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I hope I'm not hijacking this thread, but can prop twist that is visable before it's even bent be taken out by scraping on the strong side. Or is it only twist that happens when the bow is strung/drawn?
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Prop twist that is present before brace is most likely the result of the grain of the wood and the way it dried. There may or may not be a "strong" side. I would use heat to try and "untwist" if it is causing problems. Some of my bows just have a little twist to them and it doesn't seem to hurt them when shooting.
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Thanks for clearing that up. Looks like I need to go find my heat gun.
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Here area couple of tips for other bows.
First leave the nocks wide...like an inch. That way you can cut the nock deeper on the offending side.
Second, leave the handle wide...ful width. That way you can finish the handle so that the string tracks.
I don't usually fuss to get the string in the center. If it is on the handle I am happy. Then I can play the 2 points above.
Jawge
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agreed prop twist is better taken out with untwisting with heat,,
what Jawge said on lining the string,, I will bend at the handle if needed,, doesnt take much,,and I am not that fussy about it,, I just shoot the bow with the string to the arrow side,,if it shoots well I leave it,, I will fine tune if I think the arrow is not acting right :) most of my bows are osage,,, so i have become accustomed to dealing with twist ,, dog leg,,, whopptie doos,,, and not being able to line everything up,,,,but still getting a good shooter,, aligning the bow and tips and handle to the string as well