Veneers, especially those from burls, have a tendency to buckle and warp over time. Here's a technique for flattening veneers while enhancing their strength and flexibility:
Create a flattening solution using the following formula:
- Four parts water
- Two parts glycerine
- One part alcohol
- Two parts plastic-resin glue
Mix thoroughly. Use a paintbrush to apply the solution to both sides of the veneer until they are saturated
Then, to dry the sheets flat, place the sheets within a "sandwich" made using wood cauls, a few sheets of newsprint paper to absorb moisture, and fiberglass window-screen. Lay the veneer flat, adding a piece of fiberglass window-screen on both sides of each veneer. The screen prevents the veneers from sticking to the newsprint as they dry.
Top the sandwich with a second wood caul. Use even clamping pressure (figure F) to squeeze out the excess solution and make the veneers flat.
After waiting a few days, and replacing the wet newsprint with fresh, dry sheets a few times, the warped veneers should come out perfectly flat.