Primitive Archer
Main Discussion Area => Bows => Topic started by: Prarie Bowyer on April 12, 2012, 08:38:36 pm
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Hey guys.
I got a little overzealous with the spoke shave when rounding my belly on another ELB thing and now I have a twisting limb. It only twists when the limb is flexed. I can never remember which side to focus on to fix it. Looking down thelength there is a bit of a hollow on the limb. No real hinges. I thought I'd be clever and take a belly scrap, which is tapered, clean it up from saw marks then radicaly grind one part of one edge and see what was happening when it was flexed.
See I can never remember if the wood dives on the weak side leaving the other side standing up or if it pulls down on the stong side and the weak side comes up.
At one point I had it almost out then I think I confused which ends were which and I put it back in. Now I scrape on the high side and I don't see anything getting better. So I scrape on the low side and I don't see a change.
Back to my scrap experiment. Tt was bending flat, then I ground it some more and it LOOKS like it goes down on the thin side leaving the thick side high.
The limb just has a noticable amount of twist in it. It is coming along great otherwise. I'd like to fix it quickly so that I'll have a higher draw weight bow.
What do I do to fix it?
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Someone here posted a wonderful thread explaining how it all worked. Once I read it I was not surprised why every time I tried to fix a twisting limb I only made it worse.
You take wood off the side that dives in. It's counter-intuitive, but it sure worked for me on the last bow that gave me those twisting fits!
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The wood will always bend toward the weaker side of the limb (generally that means the thinner side). If you want it to twist the other way, you need to take wood off the stronger (thicker) half of the belly.
Here's the link you're looking for:
http://www.primitivearcher.com/smf/index.php/topic,27206.0.html
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AHA! That was the exact thread I had in mind!
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Thanks guys. I set that bow aside for a bit but I'll be back into it tomorrow.
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Wait...What!.
This should be simple and possibly it will be when I'm not reading at 11:20 PM.
the Rt limb flexes away from me on the tree and literaly twists as it goes down
I scrape where to fix it?
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Unless I am reading this wrong, I thought that was obvious? (what the link explained.)
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Is your centerline dead straight?
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Now I've done it to anther bow and this methods seem not to be helping. I've gotten it a bit less but I'd like to get it out.
I think the tow bows came from the same section of the same board. I'm wondeing if it is a grain thing? Both have rounded bellies. so either the common element is the rounded belly, or the same board.
The next one I do I'll wit till it's tillered to round the belly and work more slowly. The last two I tried to rough them in some then clean up the tiller and get to draw length weight.
If it is grain oriented in nature can it be fixed? It's odd becasue it's a triple laminate.
Thanks,
PB