Primitive Archer
Main Discussion Area => Bows => Topic started by: DC on August 22, 2017, 07:20:22 pm
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I've steamed a couple of recurves in a piece of Yew. How long should I leave it before I "lock in" the bend with dry heat?
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No dry heat necessary, just let it dry a day or two and you're good to go, never had one pull out.
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I've never done that with anything I've steamed.
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Only need to do it if you find they are pulling out.
Mind it won't do any harm, so if you want to do it, give it a day maybe... I generally just leave stuff overnight to settle.
Del
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I do it to all the steamed in recurves, makes sure they won't pull out especially if I'm going to heat-treat plus it strengthens the wood. I do it right after the wood cools and before I pull it off the form. That way it stays exactly the shape I bent in.
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I do as Mark does, never had one pull out since I started doing the dry heat after the steaming. I think the dry heat stiffens them up also which helps in making them thinner and lighter
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Thanks
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Consider your local conditions too. Some steamed woods really like to straighten out if moisture levels rise.
You'll probably see a correlation between guys in a desert type environment saying dry heat is unnecessary and guys in a high humidity area or variable humidity liking the additional hold that dry heat gives.
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Wow. I've never done that and now I feel like an idiot. Sounds like a great idea!
Thanks :)
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All woods are different, I don't believe it is necessary in all woods.
DBar
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I do exactly like Marc does, right after. I pretty much always do it now. It doesn't hurt and often helps.
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The only way it could help is by somehow stopping the cells taking on moisture again. Concave bellies after heat treating would suggest that this happens to a degree but you would need to get the recurves very hot for a reasonable length of time. This would need a narrow form and clamping of the recurve.
I would suggest that recurves that pull out are either too thin or more likely the heat didn't penetrate fully into the center of the recurve and therefore you have opposing forces 'steamed in'. Eg. the outer fibers got hot enough and are happily sitting there in the shape you want but the inner wood is still trying to straighten.
Boiling is my preferred method now after bending many hornbow cores I know it gives more consistent results for anything upto the most extreme bends you can get into a straight piece of wood.
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The tip IS on a form. We do know dry heat alters wood so it definitely makes more of a difference than just preventing moisture uptake.
If we could just heat treat in sharp recurves we probably would for the potential increased benefits but generally steam and boiling is the only way to get the shape there first.
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I temper my extreme bends with dry heat on the form a couple of days after steaming.