When assembling with glue, it is important to apply instant pressure to the
two joined pieces as soon as the glued surfaces have been brought together.
Screws should be fastened immediately to effect this pressure and, where
necessary, clamps should be brought into play. An inexpensive system of
clamping down a large area without going to the expense of buying dozens of
clamps, is to make the simple wedge clamps shown in the photos. These are made
of 2-inch thick hardwood and function very efficiently by means of small
wooden wedges forced under them.
To use the wedge clamp, slip it over the freshly glued and joined pieces,
then force a pair of small wooden wedges under the upper iaw, driving the
wedges in from opposite sides until the desired pressure is brought to bear
on the glued pieces.
Do not force the wedges in too much or the clamp may break. The correct
amount of pressure is reached when glue begins to squeeze out of the joint.
To protect the surface of the wood from injury, slip a sheet of heavy
cardboard between the clamp jaw and the good surface, and drive the wedges
only on the underside of the panel.