Friday, February 18, 2011

Clamping veneers...

I left off with jointed veneer slices. I usually use two different methods to create wider sheets of veneer from narrower individual pieces. If the veneers are 1/8 in. or greater in thickness, I clamp them using very light clamps and weigh the sheet down afterwards to keep any of the veneer slices from buckling. This method works well for me and the photo illustrates how I do this. The other technique I use is to tape the two halves of veneer together and use the tape as the clamp. I place blue tape at regular intervals along the length of the veneers halves and make sure to do this on both sides of the veneers. This method works well with thin veneer slices as they cannot be easily clamped together any longer.

Another technique I sometimes use is to spring the joint, that is each side of the joint is so very slightly concave, there is a minuscule gap at the center of each of the slices. This technique only really works when clamping veneer halves together, veneers which are thicker than 1/8 in. The reasoning behind this is that when the center portion of the slices are clamped together, the ends of the slices are so much tighter there is little opportunity for the joint to open up. This is purely cautionary though, as once the veneers are laminated to the substrate there is little chance any of the joints will open up anyway.

3 comments:

Tico Vogt said...

Hi Norman,

A luthier friend has a nice way of clamping thin boards by a simple set-up using opposing wedges. He fixes one straight stop the length of the material, and two long, slightly tapered wedges, the outer one fixed. Just place the boards to be glued together in place with one edge against the fixed stop and push the free wedge until the boards are pushed tightly together. It's simple and effective, avoids clamps, and he's used it to make hundreds of guitars.

Norman Pirollo said...

Hi Tico,

I am aware of the sliding wedge method but I got hold of these light clamps I wanted to experiment with. Tried this method, it works well. It might not work with heavier clamps though. These particular ones have a flat base so minimal stress is placed on the boards being clamped aside from the small clamping pressure. Also I raise the surface of the veneers a bit with a 1/8 in. board underneath and then I weigh everything down.

Tico Vogt said...

What clamps are they?