Primitive Archer
Main Discussion Area => Bows => Topic started by: bubbles on December 29, 2013, 12:20:50 pm
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Hey guys,
Just wondering what you think I can get out of this stave - My draw is around 25" for a bendy handle bow.
Think this one can make 40# or above? This is my first black walnut stave, so I'm not sure of the limits. It's about 1 1/4" wide at the handle area. Some small pin knots in the back and about 2 1/4" of reflex. Heat treat? Think it can handle the reflex with just 1 1/4" wide? Total length is 55" and had a fairly high crown.
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Bubby, you should be able to get 40# with a bendy handle bow from this sapling. I would heat treat the belly and not induce too much reflex. The less you stress the belly the better. Keep the limbs wide for most of the length before tapering to 3/4" like the Eastern Woodland bows.
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That's gonna be tricky with that diameter sapling. I agree with Pat on the bendy handle. You'll need every bit of your length working. The high crown is gonna be a problem though. I would highly recommend a rawhide backing. Sinew would be even better. Ordinarily I would recommend decrowning, but you don't have enough wood for that and still make your weight. Josh
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Yeah, definately bendy handle. Would it be a good idea to reduce
some of the reflex when heat treating? Taking a bit more stress off the belly?
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The hitch in your giddy-up is gonna be tension strength not compression. The high crown is already in danger of failure with out heat treating. That's why I suggest you back it with something substantial like rawhide or sinew. Walnut will take a little more set than most woods so your reflex will go away pretty quick in the tillering process. I wouldn't try to reduce it any with heat. The other issue you are gonna run into is walnut has a pith channel. If you try to temper it with that channel, it will check all along that channel. One other thing to keep in mind in regards to the pith channel, be sure to radius or round off the edge of the exposed portion of the channel as its exposed during tillering. This includes the part where the channel transitions from exposed to unexposed in the thicker part of the bow. I hope that helps. Josh
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I'd try the hollow limb design. I plan on trying it at some point. Perfect for small saplings
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Perhaps this is a good candidate for my first sinew job, combined with my first Hollow limb job. :)
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Sinew...yes. hollow limb....maybe not so much. Unless of course you are shooting for a ten pound bow ::) lol! Otherwise, I would hold off on the hollow limb design for a little bigger stave. Josh
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bubbles,
Don't know where ya are in your bow building career, but believe you cant do better than taking what Gun Doc says and applying it. Doc's made some fine walnut stave bows. My experience is with quarter sawn walnut that I cut/mill myself so I casnt directly help you out.
rich
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I'd take gun docs advice although for me compression strenth has always been more of an issue then tension when talking about walnut
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Heat treating the belly will help increase the compression strength.
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Yep, I'm going to follow the advice of the doc. :)
I've got it roughed out and started to bend it a bit, but I dont' think it's quite seasoned yet as I cut it at the beginning of Oct. I'm glueing on the nock overlays right now, but I'll probably let it sit a few weeks more before I start tillering, then heat treat, then sinew.
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Doc's advice sounds good for that sapling and it should be doable for that weight in a bendy design. I had a similar walnut sapling stave although mine was about 1 1/2" width and straight with no reflex if I recall. Had a crowned back and was left pretty wide out to near the tips. Lifted a splinter that I filled with sinew and then did a sinew wrap over it to hold it down. Rawhide backing would have prevented that but it has held strong since. Did take a bit of set but has shot fine since finished nearly two years ago. Here's a link to how it turned out if you want to follow this design option.
http://www.primitivearcher.com/smf/index.php/topic,33670.0.html
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Looks good BB. That gives me faith I can get 40 out of it. I've roughed it out and got it bending a touch, but its still loosing a few grains a day, so I'm gonna set it aside for a few weeks. I've just finished a batch of glue, and my sinews are drying so hopefully it turns in to a nice shooter!
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Just an update about this stave and a question - I had it bending to about straight and I've let it dry out the rest of the way. I'm gonna tweak the tiller a bit more now that it's dry, but a question - would it be good, once I'm happy with the long string tiller, to reduce weight by de-crowning? Effectively tillering backwards so that I preserve the width of the stave and remove some crown? Then once I've gotten it to brace height, heat treat, and sinew the de-crowned back, and resume normal tillering - would this be a good way to go? It's only gonna loose width if I start taking more belly wood off.
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There are still some pith channels visible near the top tip, as the pic shows. Anybody think that will be a problem?
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The pith channels won't hurt a thing. You can decrown it to save your width, BUT...don't get carried away! Very little wood off that high crown will make a huge difference. Josh
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Allright, I'm getting to the end of tillering - thought I'd get some opinions on where to go from here.
It's 40#@23" and I'm having a little trouble dropping the weight. What do you guys think so far? The last half of the bottom limb took a lot of reflex from the sinew, while the top limb stayed pretty straight. What`s the procedure for tillering after sinew has changed the way the bow is in the unstrung profile? It's currently at a 5" brace, which I though was sufficient since it's a short bow.
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if you apply the sinew evenly you shouldnt have to do much retillering after its cured.
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I guess the sinew was not applied evenly then.
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opps i guess i miss read that. if the bow is bending evenly when drawn then i wouldnt worry about the unbraced profile. the tiller looks good to me.
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I wouldn't be that concerned about the reflex as it is unstrung. Tiller is more important. And it looks to me like you did a very good job on that. I've made a few walnut stave bows and sinewed all of them. Such is the nature of walnut. They do make a beautiful bow in my opinion. One of the nicer looking woods. They just need some help to make them efficient and durable.
Nice Bow!
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Cool, thanks guys, I guess I'll just take it slow and careful for these last few inches.