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Main Boards => The Bowyer's Bench => Topic started by: PEL on February 20, 2013, 09:41:00 AM

Title: fixing slight limb twist
Post by: PEL on February 20, 2013, 09:41:00 AM
Hello all!  First I want to thank EVERYBODY for the fabulous advice and great posts - I dont post much but I read a ton and learn lots from all of you.  I have been building bows for 3 or 4 years now and have started producing adult sized bows that actually shoot!  I build both laminated all wood or bamboo bows and I am working on some great self-bows as well.
( I will post some pics sometime as I have always been inspired by all of yours)


I am still confused about one topic in particular - (I did a search but no joy).  I just completed a bamboo backed yew bow, essentially a board bow build from the slats left over from my cousin's yew self-bow.  I have noticed that the string does not track the center of the handle and the problem seems to be focused in one limb which twists slightly to the side.  

SO - should I attempt to correct this by removing wood from the belly or the sides?
Also, most importantly, do I try to weaken the side it is bending TOWARDS (looking at the belly side) or the side it is bending AWAY from?

My confusion is rampant.  Thanks in advance for advice.

Paul
Title: Re: fixing slight limb twist
Post by: Pat B on February 20, 2013, 11:29:00 AM
Paul, is the twist in the limb when the bow is unbraced or just when braced. If when unbraced you may have glued in the twist. If only when braced feel the thickness of the limb from one side to the other. If one side feels thicker that is probably the culpret.
Title: Re: fixing slight limb twist
Post by: PEL on February 20, 2013, 01:31:00 PM
Thanks for the quick reply Pat!
the twist is only there when the bow is braced.
when I get home I will check the thickness on each side - might be slightly complicated because the bamboo backing might not be perfectly even in thickness either... so the two sides COULD be the same thickness but one side could have more yew the other more bamboo...
Of course I should remove wood from the thicker side if there is one.  
I am still wondering - will the limb bend away from the thicker (or stronger) side (which makes a kind of sense to me) or towards the thicker side?
Title: Re: fixing slight limb twist
Post by: Roy from Pa on February 20, 2013, 04:04:00 PM
The limb will bend towards the weak side so remove wood from the opposite side.
Title: Re: fixing slight limb twist
Post by: Dimondback on February 21, 2013, 12:32:00 PM
QuoteOriginally posted by Roy from Pa:
The limb will bend towards the weak side so remove wood from the opposite side.
I just "fixed" a PSE of my brother-in-law's using this method a few weeks ago. I used a 10" sanding block and sanded the opposite side in the mid-limb area until the limb straightened out. This was on a laminated recurve and it worked like a champ. Good luck!
Title: Re: fixing slight limb twist
Post by: PEL on February 21, 2013, 04:27:00 PM
Thanks all!  I will gently sand the strong side as there is no measurable difference in thickness.