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Main Boards => The Bowyer's Bench => Topic started by: razorback on February 13, 2009, 10:12:00 AM
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What poundage could I expect to get from an osage bow that has 30" working limbs is 1 3/8ths" wide and about 3/8ths" thick. What would be the best design. It is almost straight and has about 2" of reflex after heat treating.
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with 30" working limbs and an 8" handle you are looking at at least a 68" bow and when you add the tips, more than that. Are you starting off with a full stave? Have you cut it to the dimensions you mentioned?
IMO, you should make the bow appropriate to the stave and not the other way around. At 68" and 1 3/8" wide you can make a bow of whatever weight you want. Osage is a tough bow wood. If your draw length is 28" and your stave is 1 3/8" wide, cut it to 66" long and you can easily get a bow in the 60# range and way more than that if you wanted. The thickness of the limb is determined by the design and draw weight, not a predetermined thickness...at least not for me. Pat
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Pat.
This is the stave I have been working on for a while. The thickness will come if I remove one more ring from the back to get rid of that crack in the handle area. The thickness comes from the back and the belly being effected by cracks in the stave that ran along rings. It is reduced to 1 3/8 wide which is what I got from the stave once back ring was chased. I could leave the back as is and work with more thickness but thought I might just be able to get rid of one more problem. It also developed a check in the back when I straightened it. Might not have been as dry as my moisture meter said. With removing the ring I might get rid of a lot of that check also.
I guess what I am looking for is a design that will work within the parameters that I have.
Tony
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A pin type moisture meter will only measure the moisture between the pins and not necessarily the enternal wood M/C. That's why I gave my moisture meter away to a friend from Utah that needed to be sure his wood wasn't too dry.
What is your draw length and your stave length? The 1 3/8" width is good for osage bows. If your bow is long enough and you come in under weight you can reduce the length to increase weight.
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What poundage could I expect to get from an osage bow that has 30" working limbs is 1 3/8ths" wide and about 3/8ths" thick.
You can’t think about wood bows that way. It's fiberglass mentality to think that, "so much width and thickness equal a certain poundage, etc."
Wood is organic and seldom behaves uniformly, unless it's a wood composite bow.
Thoughts on osage bow design on my site: http://analogperiphery.blogspot.com/2008/05/osage-flat-bow-dimensions.html
Hope that helps.
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3/8" is too thin to get much more than a 30# bow unless you make it 2" wide or more. It will also be extremely tricky to tiller. Best choice is to leave the ring on and deal with the cracks in another way like gluing and wrapping. As long as your handle is not bending, you do not have to worry about cracks in it.
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I know this is not the way to think about a wood bow. It is, unfortunately a product of the material I have to work with. the stave is 67" long with one limb being 29" and the other being 30". handle was dictated by a large knot hole which gives me the 29" limb. The bow is already roughed to these dimentions with belly fades started. My draw length is 29" with a recurve but I believe will be shorter with a longbow. I can leave it thicker as the crack is in the handle, which will give me more material to work with.
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Thanks John.
that is sort of what I was thinking of doing. I just wanted to check with those who have done this to see what my option are. being new to this and having a stave with issues i don't want to rush into it and spoil something that could be good. there is a real good chance that this bow will come to a quick and catastrophic end, considering all its flaws, but I want to do the best I can by it and learn as much as possible in the process.
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You're doing real good. Have fun. Good luck!
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You can build two selfbows,same wood,same dimentions. And they will act different the weight will be different.You can do this with lam bows but not wood bows.Wood is wood.
Dead is dead no matter now fast your arrow gets there.