Primitive Archer
Main Discussion Area => Bows => Topic started by: RyanR on November 22, 2013, 09:21:38 pm
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Steamed this elm for 35 min and put it on the form and bent it around and "crack". I still have 3/8" to work with so I may be able to salvage it. I still have the other side to do so any suggestions would be helpful. If anything I can learn from this by doing the other side correctly.
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use banding material or a thin metal ruler under the clamps and along the belly of the curve. discourages anthing lifting.
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The banding works but sanding the edges also helps
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A thing that I would try if i wanted to have a non bending recurve, I would glue it together and wrap b50,artificial sinew, sinew, tooth floss, around it. You have two perfectly mating surfaces and just wrap some of that stuff on, tiller it, then wrap in some decorative wrap on both sides. Works like a charm and you are the only one that knows about it.
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Steam it longer or boil it. It's pretty unusual for a splinter to lift that close to the tip. Usually the wood will separate right at the apex of the curve. I find Elm to be by far the best wood for bending. I have only found one tree that for whatever reason basically refused to bend without cracking.
I never use a supporting strap for elm.
ps Soaking the wood for a couple of days will also greatly increase the bending capacity.
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Laminate a new piece on the bottom of the broken one.
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Definitely do as Sleek suggests and also get that splinter cut off at the max depth to stop it from extending.. You can also bandsaw out a piece of wood to match the curve and make a Grumley style brush nock. At least try to get the second one bent without cracking even if you end up reducing it to match the other.
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I got the second one to bend with only a slight split up on the bend like PatM had mentioned. Definitely I need to get that splinter off so it doesn't travel farther. I would like to laminate a piece on the bottom like sleek said. Might be kind of hard without a band saw. I don't care if the tips bend or not. I am not sure it makes a difference because this is my first recurve build.
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You can also reduce the width at the apex of the bend to ease bending there.
Soak, boil, metal strap is my method. Then this never happens.
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I only tend to get a splinter like that if the belly is not flat and down to one even growth ring.
If that's not possible I use a metal ruler as a strap. I boil for 45 minutes.
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It looks like you will have eplenty of thicknessd left after you clean it up. Temper it after you clean it up and dont bend it for a day after. I never use a strap. Tried it on my first and never again. Cant see how a tension tear can be stopped by a flimsy strap lightly pushing on the woods surface.
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Use a 1/16" thick lam to glue over it once cleaned up...you won't have to heat bend it...it will be thin enough to conform to the shape of the curve ....plus your curve will look better aesthetically ;) and next time steam/boil it longer...most white woods need more time being coaxed with heat to move compared to woods like osage/yew/junipers etc...
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Use a 1/16" thick lam to glue over it once cleaned up...you won't have to heat bend it...it will be thin enough to conform to the shape of the curve ....plus your curve will look better aesthetically ;) and next time steam/boil it longer...most white woods need more time being coaxed with heat to move compared to woods like osage/yew/junipers etc...
I think you are right with the boil time. I should have boiled it longer. When it let loose it sounded like it was tearing. Not sure how to do the laminations. Limited on power tools.
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You don't need power tools for that. You can get a large sheet of sandpaper for a floor sander and stick it to a board and use it as a "belt sander" to make flat laminations.
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You could also always try gluing that splinter back down. It is a perfect fit you know....Just be sure to get plenty of glue in there and inside the end of the crack well so it doesnt continue to split. Then when you clamp it down, be sure to not clamp so hard all the glue squeezes out and wind up with a weak dry joint.