Primitive Archer
Main Discussion Area => Bows => Topic started by: bubbles on September 07, 2013, 02:36:24 pm
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Hi guys, Just wondering how you go about clamping spliced billets together during glue up - I searched and haven't been able to find to many shots of the actual clamping and glue-up. Lots of info on how to cut the splice.
Do you need to apply pressure lengthwise along the bow to mash the splice together or do you just clamp sides of the splice together?
I guess I could put 'C' clamps on both limbs and then take 2 pipe clamps on either side and clamp the 2 'C' clamps together - That would squeeze the joint together lengthwise, but I dont' know if that's even necessary.
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A couple of the sites drilled a 1/4" hole through the stack and pushed a dowel through to keep the splice from pushing apart. That doesn't sound wise to me. Why weaken the joint? I would do what you suggested and clamp it lengthwise. What I'm going to do is put a block on either end of a 2x4 the length of the bow apart plus a bit. Lightly clamp the glued up bow between the blocks and push a wedge between the end of the bow and the block. This should push the splice tightly together. Then clamp the splice.
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I just bind up with good ol' rubber strapping. I try to get a snuggish fit tha tdoesn't need clamping. Too much pressure can squeeze out the glue. If the splice is good ist should need end on pressure, although I have wedged one lightly betweenthe walls of my garage before now.
Mind I've prob only done three or 4 splices, so I'm not an old hand.
Del
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Do NOT clamp lengthwise. Don't even bounce the bottom piece on the floor to 'seat' the two together. The points of the splice can act like a wedge and split your billets before you can say "Oh $#!^". Don't ask how I know :(
Take your time to fit them up as nicely as you can, so that the joint is well mated when firmly slid together by hand. Then clamp with moderate side-to-side pressure only. I use two small c-clamps. Proper mating is what makes for a good strong finger splice... not force.
I've never pinned one. I've done bunches of them... no failure yet.
Some folks steam them, clamp them together without glue and leave them cool/dry... which helps them fit to each other, the disassemble, glue and reclamp. I find it faster, easier, and makes a better joint if I just do my best when sawing them out.
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Do NOT clamp lengthwise. Don't even bounce the bottom piece on the floor to 'seat' the two together. The points of the splice can act like a wedge and split your billets before you can say "Oh $#!^". Don't ask how I know :(
I agree with this. I didn't mean to suggest a really tight end clamp, more of a jig to keep the clamping pressure from pushing the joint apart. I've had trouble with that with other sloping joints. I guess really that the fingers of the joint are strong enough to prevent that unless you are putting way to much clamping pressure on. Sorry for misleading anyone.
Don
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Do NOT clamp lengthwise. Don't even bounce the bottom piece on the floor to 'seat' the two together. The points of the splice can act like a wedge and split your billets before you can say "Oh $#!^". Don't ask how I know :(
I split a paduak core I was splicing like this.
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Good to know. I will not clamp lengthwise. :) Thanks for the advice.
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There is no need to add a dowel through the splice and actually it will weaken the joint. A couple of "C" clamps should do the trick. Be sure not to glue the "C" clamps to the handle. ::) A little Saran wrap will help there. ;D Also, preshape the handle before cutting the splice or you'll remove most of the splice when you do cut out the handle.
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I cut the splices, fit them, take them apart and drill a tiney dimple into the same spot on both end of the splice. then I put a steel or copper BB into the dimple. This locks the splice together when clamped so that the splice doesnt spread apart under clamp pressure. The glue acts like a lube and its harder than you think to keep the slice still. The BB locking ball trick works great. It only takes one BB.
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Kinda like the little locking ball on a socket wrench. That's a great idea.
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Exactly...