Trad Gang
Main Boards => The Bowyer's Bench => Topic started by: wood carver 2 on December 13, 2015, 04:46:00 PM
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I was working on a longbow for a Christmas present today and things were moving right along until I strung it up. It looked like there was a bit too much bend at the tips, so I thought I would remove more wood from the rest of the limbs to even things out. I only removed wood from the fades out to about mid limb. Then I strung it up again and I saw the lower limb hinging badly about 8 inches from the tip.
Here it is on the long string.
(http://i1177.photobucket.com/albums/x349/1wood1/IMG_0641_zpsbcqidqlz.jpg) (http://s1177.photobucket.com/user/1wood1/media/IMG_0641_zpsbcqidqlz.jpg.html)
I unstrung it and it went back to it's original profile right away.
(http://i1177.photobucket.com/albums/x349/1wood1/IMG_0642_zpsrlmmkkzz.jpg) (http://s1177.photobucket.com/user/1wood1/media/IMG_0642_zpsrlmmkkzz.jpg.html)
This bow is bamboo backed and bellied with a purpleheart core and a thin walnut power lam. 68 inches tip to tip and 1 3/8 inches wide at the fades.
Is there a fix for this or is it bandsaw fodder?
Dave.
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Remove wood from above and below the hinge until it is gone. Watch the other limb to make sure it stays even.
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Thanks John.
What causes a hinge like this? The limbs are both evenly tapered and the core lam is free of defects and is symmetrical in both limbs. The only work I did before noticing the hinge was to sand to my profile and round off the edges a bit to prevent splinters during tillering. Could it be a weak area in the wood?
Dave.
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Changes in limb thickness cause exponential changes in limb stiffness .... Fractions of a mm stand between a stiff spot and a glaring hinge.