Can someone help me with sheer clamps

[Spedos]

This is my first time to the forum and I hope someone can give me an idea on how to do this. I need to replace some sheer clamps. They have both a pretty good bend and also a pretty good arc. The original one was made from mahogany. I tried to replace it with the same material and it started to crack as it was twisted and bent into place. Then I thought I would try and laminate a new one but again it this would not work either. The clamp is about 1 1/4" x 2" My question is could the clamp be made out of 6pcs of 5/8" x 1/2" which would then be glued together in the boat. If this would work which is the better material to use DF or mahogany.
Thanks

[G. Schollmeier]

I don't work with stock that size. But I think I would stick with the original size and build a steam box to fit it. It shoiuld go where you want it after a good steam bath.

Gary :D

[ 12-12-2002, 10:45 PM: Message edited by: G. Schollmeier ]

[Tom Lathrop]

I once tried that technique on a stair stringer. Finally got it to work, but would definitely not go that way again. I have always managed to force curvature into the outwhale/inwhale,rubstrips (not sure which you are talking about) with, at most, two pieces. The real problem comes when the piece curves in vertical, horizontal and diagonal (flare) planes but, if it won't work dry, then go to steam.

[Ian McColgin]

Steam for sure.

Easiest steam box is made up from styrofoam sized to just fit your piece and sealed up with duct tape.

Have the thing tilted slightly so that the tube that carries steam up from your boiler will also return condensed water. But keep an eye on the pot as you'll still need to add water.

If you can clamp and then bolt it in place, fine. Otherwise, try hot clamping it in place but have shims available to provide a bit of over-twist and over bend.

G'luck

[Thad]

Your new piece of Mahogany might have had a few problems with the bend. 1, grain runout. 2, Kiln dry and brittle. It is hard to get Mahogany where I am not kiln dry. Steaming might make the bend and twist possible, but will not make it really flexible. Working with another species like yellow pine or Douglas fir might work better if you can get stock that will bend. Fir can be tricky because it will often bend in place as though all were fine and then days later it will break with a bang.

[Bruce Hooke]

I don't know where you are but if you are somewhere where you can get white oak, and especially green white oak, that might be a way to go. Green white oak, or partially dried white oak, with nice straight green, will bend into a much tighter curve than dry mahogany will. If you need to resort to steaming then steamed, green white oak can be very nearly tied in knots it's so flexible. I believe white oak is stronger than mahogany so strength should not be an issue, but you might want to get a second opinion on that.

[Ross Faneuf]

I've successfully laminated a mahogany sheer clamp in place. But we need to know how big the boat is. I sure don't understand how you'd get a 1 1/4 x 2 clamp out of pieces of 5/8 x 1/2.

[Spedos]

I think I will try steaming it in with some green oak. There is a saw mill not far from where I'm at.