Primitive Archer
Main Discussion Area => Bows => Topic started by: Fox on November 26, 2023, 02:21:53 pm
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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
(https://live.staticflickr.com/65535/53357731084_afa6765cb1_k.jpg) (https://www.flickr.com/gp/141458655@N02/g86NSL10x5)Untitled (https://www.flickr.com/gp/141458655@N02/g86NSL10x5) by Livvydog (https://www.flickr.com/photos/141458655@N02/), on Flickr
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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
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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.
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Maybe just wrap it in sinew and carry on?
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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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Most time the pin knots with show a crack at some point, the problem with them depends on which way the go, if they go longitudinally usually no problem at all but it the go across the limb the will almost always fail at some point at least that is my experience, I would fill with thin super glue as was said and wrap from above well below the crack and that will probably take care of it and is about all you can do.
Pappy
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Thanks for all the advice all be it man Different opinions haha… going to leave it as is to finish out this hunting season with it. I have some sinew I have been thinking about putting on it anyway so maybe I’ll do that when the season ends
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If it were me and it ant I would at least wrap it now. Pappy
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I asked the same thing about a cracked pin knot recently. Here’s the link:
http://www.primitivearcher.com/smf/index.php?topic=72003.0
I got mixed opinions and ended up trying to break it on purpose. Drew the 52” ttt bow to 32”. I pulled it as hard as I could until it reached a mechanical lock from the severe string angle. It didn’t break, the crack didn’t grow, no compression failure, and barely took any string follow after the torture. After that day, I have no worries about tiny cracks across pins at all.
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Good idea pappy, I’ll glut it and wrap it. That’s a very interesting post organic archer! Lots of good info there on the topic. Thanks!
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I can remember quite a few bows on PA over the years that broke in tension, or developed a chrysal right at a pin knot. It is true a lot of guys get away without compensating for them. I don't think it's by design or skill. It's sometimes safe because the bows are actually slightly overbuilt, or longer than normal.
The same guys that get away with it try it with a more highly stressed bow that is a little shorter, and or narrower, come on here and ask why their best bows have blown up when shooting. I had to learn the hard way too, before I figured out how to avoid the problem in the first place.
A pin knot is a literal break in the long grain, it just doesn't have the same strength as straight grain. It is an inherent weak spot. Compensate for it and you eliminate any potential problems. Its also a lot easier and cheaper in time and money than having to repair, or scrap a problematic bow.
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Rough the back, and sinew back it now. It will be good for years to come in my experience, and I have violated back growth ring Osage bows sinew backed that have never failed me to date. Some 15 years old with a lot of arrows shot through them.
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I’ve had my pin knots to deal with lately. The best is not to have them. But I’m almost all out of that wood!🤨🤨
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Yeah that’s my problem to selfbowman (Arvin? Is that your name, right?) good Osage is hard to come by around my neck of the woods
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If it were me and it ant I would at least wrap it now. Pappy
Plus one for me. Especially if it’s my hunting rig. You can always sinew back or hide back after the season is over for later more permanent fix
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Based on the multitude of experts chiming in here the answer is probably “it depends” and “your mileage may vary”. IMO, with bow making there is always some risk with a material like wood. If it helps you feel better about the bow and shooting it, then secure the crack with a backing or wrap. If you don’t care and feel comfortable accepting some level of risk of breakage then don’t bother. It’s never 0% risk. Just how much risk you’re willing to accept.
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True Ryan. Yes fox I’m Arvin.
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Arvin, I put a drop of super glue on any pins, back or belly just in case. It only takes a minute or 2 and doesn't cost much so why not. I do the same with most knots. And, if you are feeling really creative you can do this...
(https://i.imgur.com/gSjDlvA.jpg)
This was a bow at the Classic on the table of the stave salesman, Jim from Oklahoma.
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Awesome work, Pat.
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Love it Pat. Very creative. I agree. A drop or 2 of a thin super glue will never hurt whether or not it helps. Sure nothing to lose.
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I wish I had done that carving but it was someone else. The belly side was the coons tail end.
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Did Kenny do the carving? Cool for sure... It's funny how many different views there for something as simple as a pin knot. :) That's what keeps it fun... :OK
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If I was a betting man I would say Kenny done it, he is very talented and can seem to see things in a piece of wood not many can see. Pappy
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True Kenny has a lost art when it comes to folk art. Truly blessed. Met Kenny At OJAM some years back
been friends ever since. I’ve seen the Coon before.
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Haha got busy and hadn’t checked this post in a bit. Lots of cool stuff happening here now, such a cool community. I’ll wrap it so it doesn’t blow up right before I shoot that big buck ! That’s an awesome carving