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Tiny crack on pin knot

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Fox:
There is a tiny tiny crack that showed up on a pin knot on this osage bow. I don't think I violet the ring there but must've done something. Any thoughts on repairs? or is it done  :P
Untitled by Livvydog, on Flickr

Bob Barnes:
First thing...to my old eyes it looks like you did an excellent job of following a ring and working that pin knot.  I may be wrong, but I don't see a problem.  I would put a little thin super glue on/in it, not too much anywhere except the crack, because it can show up under a finish.  After it dries well...I would think you should just watch it, but soon forget about it.  If it ever looks like it's starting to spread, there's always rawhide or sinew.   :OK

Hamish:
The problem is not that a ring wasn't followed properly. The problem looks to be(I can't be sure because as I can't see the other edge of the limb) is that you didn't compensate for the knot, in the width of the bow, at that spot. Pin knots have significantly less strength in tension and compression than clear wood, so there is effectively not enough tension strength at that spot. If a pin knot is 1/8", then make a swell in the width 1/8", at the same spot.

Some people are lucky, or overbuild the bow and get away with it. Will it break anytime soon? Maybe. Its just as likely to break catastrophically without a further apparent degrade, as it is to slowly show an increase in the width of the crack, or go no further and shoot safely.

If it were mine I'd back it with rawhide.

Digital Caveman:
Maybe just wrap it in sinew and carry on? 

Eric Krewson:
OK I have built a LOT of osage bows, little cracks over a pin are fairly common, no big deal, like was said a drop of superglue in the crack is a good idea.

You don't have to widen a bow to compensate for a pin knot. It is unlikely your bow will ever fail at that pin.

Here is another myth; a pin knot on the edge of the limb will cause a limb failure, hog wash. My personal bow had 5 different sets of pins on edge of the limbs, here is an example.

In 28 years of bow building and over 150 osage bows under my belt I have never had a small crack at a pin or pins on the edge cause a limb failure.

 

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