Primitive Archer
Main Discussion Area => Bows => Topic started by: organic_archer on January 24, 2023, 08:51:08 pm
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Hello, all. I've noticed these tiny hairline cracks across pin knots often when working with yew, but I can't remember the last time I've seen them on osage. I know they've come up at some point in the past, and I probably discarded the bow before it had a chance to break. I'm giving this one a pretty good stretch by shooting it at half its length, but it's taken zero set. There were no audible ticks or otherwise alarming happenings. I've fired probably 500 arrows out of it.
Luckily, it's not customer work. It’s just one of many test bows built when adding a new bendy handle bow to my lineup and seeing how far I could push it. It's been greased up with regular coats of 60/40 tallow/beeswax, so there's no backing it.
In your guys' experience, have these been an issue? It was a pretty wonky stick, so I won't be too sad if it's not gonna make it. Profile and FD pics included.
52" long bendy
51" ntn
1.25" wide
49# at 26"
(https://i.imgur.com/UlV8GJy.jpg)
(https://i.imgur.com/U6zqIlm.jpg)
(https://i.imgur.com/SgBWXqz.jpg)
(https://i.imgur.com/n06QRI2.jpg)
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sinew wrap it with hide glue so this does (--)n't happen
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I would say it might hold up,, just guessing,, but you can back it,,if you use lye or draino will take off the finish,,rinse with boiling water,, it looks like you might have worked the pin knot down a bit too much, just guessing hard to tell from the photo,, nice bow,,
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Something to think about for the next one...
That is a beautiful tiller but sometimes the picture perfect tiller is not the best one for the stave.
Knotted areas are weak areas so I try to leave them just a little stiffer than the rest of the limb.
I know it is a difficult concept to get across but...
Jawge
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good point Jawge,, I working a bow now need to keep that in mind
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Yes , pins will usually get a small check if not right off over time, most always bad when they run across the limb like that one, if they run with the limb it is usually no problem, hate to say it because it is a beautiful bow but almost guarantee it will break at so point and most likely won't be long. I know everyone looks for that prefect tiller but like Jawgs I leave them areas a little stiff.
Pappy
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Brad, I only hit the knot with a little 220 sandpaper after chasing it. No slips of the draw knife or anything. The rings are fairly thick too, with a good early/late wood ratio.
Jawge, I left some meat around it. It stands proud of the back 1/8" extra thickness and has about 1/8" extra width from the grain swirling around it. Figured that would be enough to keep the integrity of that cluster of knots but sounds like I should've given it a little more support.
Edit: good to know, Pappy. Thanks, everyone!
(https://i.imgur.com/8vq5KtL.jpg)
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If it´s only a test bow, maybe you should pull it till it breaks and find out if the pin crack will be a part of the break? Could be a useful test if you´re happy with this type of high strained bow and plan on replicating this model to sell?
I have see those cracks in knots on elm bows and haven´t had one blow. But then they haven´t been that short though...
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The very 1st bow I made was in 2011 Osage, 63” NtN, 57#@28”. I shot it for about 2 weeks before finishing. It had a cluster of 4 pin that ere very close like the one you have the crack in. One day while shooting I heard that dreaded tic, and it had cracked between those pin knots and actually raised a 1/8” deep by 1/4” wide splinter. I filled under the splinter with superglue while strung, quickly unstrung, then when dry wrapped with serving thread. After a couple of seasons of 3d shooting, I cut off the serving and reduced the draw weight to 50#, refinished, the rewrapped with serving thread. Then I retired it my hunting bow every fall, and it’s still shooting.
Like suggested, I would either wrap it, or back it, and you have a good chance of it holding together.
Here’s a couple of photos of the splinter, and the bow 10 years later.
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I decided to go the Askel route and try to break this bow on purpose to see if the crack would let go. Well... It took a heckuva pull to get it back to 32" draw before it became mechanically locked by the string angle. I couldn't pull it any farther and held it between 30-32" for a while, pulling hard! I did this for 3 rounds, one of which is filmed and posted on IG.
The bow took almost no set. It had about 1" of string follow immediately unstrung from the torture test, resting at about 0.25 after half an hour. It didn't get any compression fractures and the crack didn't spread. The only noteworthy thing is the draw weight dropped from 49# at 26" to 46.5.
After ruining this bow in the name of experimentation (I won't be keeping it after all this), it's safe to say it would've held up possibly indefinitely at 26" draw.
52" bow at a 32" hold. The image isn't warped, she's just BENT!
(https://i.imgur.com/ETZH5ZM.jpg)
Immediately unstrung after 3 rounds of 32" torture holds:
(https://i.imgur.com/NsWZc0f.jpg)
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This photo is 30 minutes after unstringing and 30 minutes before the burn pit (=)
EDIT : after 3 hours rest, it’s flat again.
(https://i.imgur.com/HdA9dnR.jpg)
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What the heck?? Such abuse and still holding on.
I hope you kept the bow, she deserves to live!
J
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You oughta be banned for life for burning a bow like this!
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You oughta be banned for life for burning a bow like this!
I haven’t shot it again yet… but I have a feeling I’ve damaged the bow’s cast and overall longevity. I was pulling on it really hard with it locked up at 32”. It’s ok… it was built for abusing and testing the limits of the design and the wife says my bow rack is too full :o
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Thanks man for this very conclusive scientific approach 😅!!!
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Wow, that’s some serious strain going on. It does show you what a good piece of Osage could be capable of. Hate to see you lose it, it had such a perfect tiller, but good to see the test results. But I know I would have wrapped it, and shot it until it gave up, or I did lol.
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you could sinew back it,, and see how it compares to the self bow version,,no need to burn it,,,it will still kill a deer,,
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I was impressed by how low the bow's original set was. Even after that sadistic torture test its still got very little set, and no chrysals.
I reckon that it will make a fine hunting bow, either unbacked or with some sinew on it.
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yes Im sure someone would love to have it,, heat it into some reflex,, sinew back and gift,, )P(
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Wow! It should be disposed of properly. Just send it to me, and I’ll handle it free of charge.
Seriously, back it and go kill critters with it! Impressive bow in many ways.
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I couple months a go I built a non working handle 45lb 25 inch draw 58 inch Osage self bow that lifted a splinter at a knot cluster. I soaked it with crazy glue , and wrapped it with hide glue soaked sinew. So far so good. Watching how you abused your bow makes me think I will be all right with mine for a long time to come.
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I think arguments could be made both ways about a crack like that. Definitely some non contiguous fibers between the knots that could be a potential point of failure. Being further off the back might mean slightly more tension in that area being further from the neutral plane. But with the width following the grain, you’re not relying on much strength from that area and the crack doesn’t interrupt many fibers at all. Even after being pulled so far, I’m not sure I’d be able to trust a crack like that. Would be interesting to have kept it around to pull on every once in a while to see if it ever let go.