Making bent lamination form.

[Brian Penning]

Most of my bent laminations have been done by simply having lots of clamps to a single form.
I'd like to make a form that has 2 halves(male/female?)
The bent laminations required are 3/8" thick, 2" wide, 3 ft long and are S-shaped. (Think back splats for a chair.)
I've already glued up some plywood for the rough form 2-1/2" thick. Can I simply make a S shaped cut in the ply form to split it and that's it?
OR do I somehow have to remove 3/8" in the cutting of the form so that when I clamp the 2 halves together the pressure will be even.
If so how to I remove the 3/8"? What type of router bit do I need? I can't figure out the process.
TIA

[John Miliunas]

Brian, yes you DO have to take out material out of the form for the thickness of the laminations. Actually, you want to take more than the thickness out. Allow me to expand on that a bit. I took a bent laminations class by David Marks himself last fall. (Wonderful class, BTW!!!) What we did is used the light-weight MDF for the forms, with enough layers glued/screwed to the thickness necessary for our laminations. Cut your form halves by splitting the big panel to the appropriate form. Now, take a compass and set it (in your case) for a 5/8" gap and scribe a line along one of the patterns and cut that much more away. Why 5/8"? After you have both halves done, take some 1/8" cork, cut it into strips the width of your form and double-stick tape them to each form. On top of that, take some clear packing tape and simply run that on top of the cork and over the edge of the form. The cork will typically "make up" for slight variations to either form and the clear tape will prevent glue squeeze-out from inadvertently attaching your lamination to either side of the form. :) Hope this makes sense and is of some help. :) :cool: