Primitive Archer
Main Discussion Area => Bows => Topic started by: DC on January 19, 2016, 03:33:24 pm
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I finished this OS bow a week ago. It was 40#@28", 59"NTN. I was trying Eiffel Tower tips so about a foot of the outer limb was stiff. It was bent pretty tight. Put about fifty shot through it and "tick". Now it's fairly obvious that there was a weak point where those two pins are(where the break is) and that's why it broke there. There is a natural thickening from the pins about the size of a quarter(Canadian quarters are same size as American ones). Those are 4" tiles it's sitting on. It 'was' the fastest bow I've made to date, 158fps with a 435gr arrow.
So, had I noticed the pins and realized the danger what should I have done to prevent this splinter?
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It looks to me like you have a fairly high crown, you may have just asked too much of the stave you had to work with. I would have gone with full working limbs and possibly a bendy or slightly flexing handle design. So to sum it up you didn't pick the right design for the stave.
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Bingo. 24" of static limb on 59" isn't a good plan.
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Kind of thought so. Thanks. I honestly think that if it hadn't been for those pins it would have held up but who knows.
Now for the second part. If I now decrown it so I have about an inch of flat and then basically replace the crown with sinew would that be enough sinew to get it back up to 40#? The sinew would likely be about 3'16" thick. I was thinking about just running the sinew into the first couple inches of the stiff tips.
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Slap some rawhide on it and get the whole bow working.
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It's got this OS lump about midlimb. Would'nt sinew be easier than rawhide around this thing?
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If it was easy anybody could do it😉
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Nope. lay the rawhide down, let it dry and trim around that knot hole. Sinew sucks!
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if you do decide to sinew back,,, make sure to pull into reflex for the cure,, I have heated them into reflex after shot in with positive results,, then applied the sinew,,
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Assuming that's the back of the bow, maybe a good sinew wrap would do the trick.
I really want to love ocean spray, but pins are such a weakness with the wood, back or belly
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I work with saplings like that more than anything, except in elms, mulberry, plum, maple, etc...high crown and riddled with tiny knots, sometimes in series or staggering side to side on the face of a bow. Almost every bow I've made in the last 5 years has several of those.....
It can be done, and I usually just allow the bump around the knots to take care of themselves by stiffening that spot, letting the limb thickness fade into then out of the knot's bump..........but that may very well be WHY I start three bows for each I finish. Baby knots, along with drying warpage, twists, and heat treating make high crowns into troublemakers.
I love a high crowned sapling bow, but you need high tension strength wood, and if they are narrow, you need the length. If it can't be very long it long, gotta let the handle bend (if you didn't). Stiff tips on a short bow are a good idea, but maybe more like 7-8" next time? And if the inner limbs are narrow side to side, that handle has to do it's share.
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I agree with that and also keep in mind,, that a little less speed is ok trade off for the durability of slightly overbuilt :)
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I knew I was pushing my skills a bit but that's how you learn. You can be sure I will inspect the next OS stave for pins before I decide what design to use. I don't want to do a repair. I would rather start over. The only reason I mentioned sinew is it's something I've never done and I thought it would be a good place to try it. I'm surprised at PD's "sinew sucks". I thought a sinew bow was a goal of bowyery(word?) Anyway it will go in the "well, you tried" corner for a while. I've got a Yew bow in the works at the moment. Thanks for the input.
Don
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I don't think you were pushing your skill level,, just a little over optimistic about the stave,, we have all done that for sure,, sometimes it works,, sinew in the right application is a very positive skill to know,, everybody has a different view,,,and that's ok,,
sinew bows are my favorite,, and I have made some sinew bows that sucked,,but I love a well made sinew bow,, they are smooth,, fast and shoot with less than no hand shock,, I am sure you can make a repair when you feel like it and get a great bow out of that stave,, :)some of Jay Masseys hunting bows were sinew backed,, and Ishi,, so you are in good company when you carry one to the woods,,
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I would call identifying a weakness and knowing how to deal with it a skill. :)
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I just got another idea DC. Try osage next time, it scoffs at such knots. Childs play in the yellow world. :)
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As long as I can get OS staves in a 15 minute walk from my house I'll keep on keepin'on ;D ;D
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Once you use osage all you want is osage, its the king !!!
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I wouldn't want to be an Osagr junkie ;D ;D ;D ;D
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Next time your on the mainland drop me a line Don, I have a healthy pile of the yellow stuff ;D
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I don't come out of hiding that often but for that, I may :D :D