Primitive Archer
Main Discussion Area => Bows => Topic started by: Zion on April 03, 2013, 01:50:41 pm
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So lately i've been making a heavy Ocean Spray bow in the warbow design. It came from the straightest piece of wood i've ever seen, but every time I string it or even bend it the whole thing becomes so side warped it's like a crescent. I would think this would be caused by uneven crown but it's quite even. What is going on???
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If your crown is even then maybe the belly is not. Is the pith still contained within the limbs? How long seasoned is the wood?
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Using green wood will do that to. Some of your bows that are only 2-3 weeks off the stump can really change as they properly dry.
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I meant the crown on both sides. ( the only crown i can really change is the belly crown.) The pith can be seen at the tips only, and i got rid of it there. Heat treated very lightly several times. Seasoned for close to a year now because i harvested the sticks last spring/early summer. It has no real set right now. I'll put some pics of the stave and bow. In the first pic it is the one on the far right.
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See how your pith runs from the side to the center?
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:( thats to bad Zee, I would just maybe use it as firewood and try 'nother piece. I have run into that problem lots with milled (kiln dried) pieces never mind staves, saplings and such.
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So Pearly your saying that the grain of the wood is directed wrong so that's why it's warping?
I won't use it as firewood, it's too good for that. Since it's my first real longbow i can do lots of tests and strength training. My 440 lb. spring scale should show up in a couple of days so i can finally weigh this thing. I think OS would be an amazing wood for warbows tho...
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It's hard to tell for sure by your pics on my little phone screen, but it looks as though the outer 6" to 8" of your limbs are thicker than they are wide. Sort of like Molly levers. If that's the case, it will be prone to bending sideways if not perfectly aligned. Especially if there is any reflex. Just a tiny bit of sideways bend at the tips will definitely cause a twist. Josh
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They are thicker than wide. So does that mean i can't have as narrow tips as usual on these bows? The thing is this bow was completely strait but when i try to bend it the bow warps, it's never happened to me before.
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Never worked on that kind of wood but I had a hickory bow do that. Two heat treats later , a bit of twisting and now it's straight. Will know by the end of summer if she will hold up.
Greg
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It doesn't necessarily mean that you can't make your tips that way. But everything will have to be near perfect for it to draw straight. On pyramids and flat bows, you have the width of the limbs to help stabilize lever type tips so you can get away with a lot more. That's not the case with this type of bow, as its narrow profile doesn't provide the forgiving stability. The wood is always going to try to take the path of least resistance when strained, so its better to keep the outer limbs on these fairly even in width and thickness. Josh
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Ok gotcha. I think it is also sketchy because the cross section of the bow is pretty much a circle, and the profile is completely straight.... so pretty much it's just a staff. I don't think the wood really knows where to bend. Since i don't harvest large enough logs not to have crown, i think with my next one i'll make the belly flat but still make it with mostly warbow proportions. It won't be traditional but at least it'll work lol. Well now i will be able to do some tests on it tho! >:D
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It twisted around while it grew.
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The grain is straight, the bow is straight, only when i try to bend it does the bow warp. Like when you are trying to brace the tension side of a maple limb. What i might do is make the belly oval on this one, (pretty much flat with rounded corners,) pike it to keep the weight and see if it shoots good. If not, it's overdrawing time >:D
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Great advice here. That is a sweet piece of OS. I know you wont give up on it. In the one pic, the leverish tips look thicker than they need to be. I bet if you take the outer third down a bit it wont fight the string so much. also, if you toasted the belly of those half lever outer thirds, but not the sides, then you make the problem worse. Take the thickness down and heat treat the side of the levers as much as the belly, and might not twist on you so much. Like Gun Doc said, it takes the path of least resistance.
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The grain is straight, the bow is straight, only when i try to bend it does the bow warp. Like when you are trying to brace the tension side of a maple limb. What i might do is make the belly oval on this one, (pretty much flat with rounded corners,) pike it to keep the weight and see if it shoots good. If not, it's overdrawing time >:D
Zion, you cant overdraw OS!!! But if you try....get it on video! But first make a bow out of that thing ;)
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haha IKR Carson! That's why i think it has great potential for warbows!!
it's funny, it was becoming to be whip tillered besides the twisting thing so i did exactly what you said yesterday night and heat treated the sides of the tips. Didn't seem to have worked too good tho. I think i'll do what i said below and flatten the belly then pike it. I know a place where i can get a thousand more pieces like this! O:)
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Still think it's twisted. How did you work the limbs down??? Did you split the stave??
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I couldn't split this piece because i needed almost the whole size of the stick for the bow. Why would it matter anyway? I've made a few bows that were completely twisted and they always untwisted when i drew them.
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I've had this with several staves of the not too many I've made. I just tend to think that, well, the wood probably isn't the same consistency all around then. And I just try to cut it so that it bends well. I won't be or look symmetric anymore, but it'll hopefully bend straight. That's what counts. Kind of treat the twist just like one that came up because you didn't cut it out straight, even though you did.
Its kind of hard to let go the idea of straightness with a stave like this, though :'(
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That pith should be centered with the high spot on the back. With the pith coming in from the side and heading to the tips that almost tells me the back isnt centered on the crown. Does the bow twist mainly to your left as your gripping it?
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Like you said Zion the cross section is almost circular. From the pics I believe the belly isnt flat enough on the limbs to guide the bow where and how you want it to bend. Maybe the stave was too small diameter for type and weight bow your shooting for?
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If the string doesn't track straight down the middle of the bow on a Warbow then the side tracking will be exacerbated.
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Thanks for the help guys.
Actually Pearly it twists to my right when i try to bend it. The back has to be centered on the crown because the bow is the original size of the stick in the handle area and limbs.(i didn't take any meat off the sides when roughing out.) I think i must've just mistreated the tips, the stave should not have had any misalignment issues and it does not to this day, except for when i try to bend it, (it's f'ed up i know but that's what's happening lol.)
So Marc you're saying that the alignment has to be perfect from the get-go, right? So it doesn't become more extreme?
I'm gonna go cut 2 inches off each tip and flatten the belly a little. It'll be cool if it'll bend straight then...
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I couldn't split this piece because i needed almost the whole size of the stick for the bow. Why would it matter anyway? I've made a few bows that were completely twisted and they always untwisted when i drew them.
Then you have been lucky. I don't know if you will understand what I am going to attempt to explain, BUT if you understand how, and what way the wood twists you would adjust the belly of the bow to accomadate it. Otherwise you would tiller the bow so looking at the belly it would slope off to one side when at rest, and when coming to full draw it would align.
VMB
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Yeah i know what ur saying VMB. The bow i made like that, though, was a hawthorn bow that twisted in it's roughed out shape so i didn't need to figure out which way the grain twisted anyway.
Doesn't matter now tho, 'cuz i just piked the bow and flattened the belly and heat treated it. Seemed to be a success, decent tiller, decent weight, decent set, i'll know what i have to do next when i shoot it tho.
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So it only has a little misalignment right bow but it's nothing i'm worried about. I think i'll heat treat it once more. The unbraced pic is right after drawing it about 4 times.
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Zee, My maple bow is a Twist, the limbs twist opposite of eachother, but it seems to cancel out and shoots ok.... :o
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The one really twisted one i made shot like s**t to be honest, (the hawthorn one) which is why i never really finished it up. Good job making yours shoot good!