Popular Woodworking 2005-11 № 151, страница 58
When working with parallel jaw clamps (as shown) it's not necessary to place clamps on both sides of the panel. The clamp's design holds the panel flat, but it's still a good idea to check the panel to make sure. Align the two (or more) boards' thickness as carefully as possible when applying the clamps. With less offset between the boards there will be less planing or sanding to completely flatten the board.
edge on the panel to check for flat.
When the glue is dry you still need to flatten the panel. If you're lucky enough to have a drum sander capable of handling the width of the panel, a few minutes of work will have you ready for joinery. You can also use a random orbit or belt sander to flatten your panel, but take pains to remove material evenly (checking for flat as you go) and be careful not to round over the edges.
If power sanding isn't your first choice, remember how we flattened the single board by hand earlier? It's time to take that same technique to the next level by flattening your joined panel.
Assembling Plywood Panels
Making plywood panels is relatively easy if you use the right tool - a biscuit joiner. While not a common task, arranging a veneer pattern to fit your project is pos-
sible with this technique. A biscuit joint on a plywood edge isn't very strong, but it will align accurately and provide stability for use with panels.
Start by using your jointer to make the same type of complementary mating joint as we discussed for solid lumber. Be aware that if your jointer has high-speed steel knives, the plywood can dull or nick the knives. Take light passes.
With the edges prepared, set your biscuit joiner to cut the pockets in the center of the edge and work only from one side of the boards. If your biscuits are placed too close to one face of the plywood, it's possible that the biscuit shape can be telegraphed through the plies and be visible on the face.
Take care when clamping the panel, though the biscuits make alignment easier. Light sanding should be all that's required to finish the panel face. PW
Using biscuits in plywood panels makes sense to more easily align the faces. But the biscuits need to be in the middle of the plywood edge as shown in the top board here. The lower board has the biscuits cut too close to the top edge. Any swelling in the biscuit will telegraph to the face.