Making Wide Panels (Laminating)
Often we need to build a
project that requires a large solid wood panel, such as a tabletop or cabinet
door. As we all know, lumber comes in different widths but, often the required
size is not available. This is one reason why we glue together smaller boards to
make a large one. This process is referred to as lamination. Of course, you
can purchase laminated panels but generally, they cost a lot more and you would
probably end up with too much waste. Making larger panels with smaller boards
is a process that is generally simple. We've supplied the following steps to
help you achieve good results.
Select a considerable amount of boards or about 30% more than what you need for
the project. Make sure that they have little or no twist and without or hardly
any cupping. If you are selecting the wood from rough lumber, you will have do
dress the wood before making your selection. To check the cupping intensity, you
may use a straight edge ruler across the board, edge-to-edge, and measure the
gap under the ruler. If a board is cupped, you may still be able to use it by
ripping the board in the center of the cup. It is often easier to remove or use
a board that has a cup rather than a twist. Twist is a distortion in the board
that results in the ends of a board not being parallel. A board twist can
sometimes be correct by cutting off the part of the board that has the defect.
From the stock you have pre-selected, choose boards that match in color and/or
have similar pattern. To find the similar pattern, lay down the boards and try
different arrangements. This process may take a while and remember you want to
achieve the best pattern. Often, achieving a pleasing grain match is more of a
feel than a skill. Move the boards around from place to place, flip them over
end-to-end and front-to-back and study the patterns; like straight grain, curl
or swirled grain or color resemblance. Once you have found boards that match,
mark the board location and orientation with a chalk for future reference.
A this point, all the boards that
you want to use to make the panel have been selected. Cut the boards slightly
longer than the required length and make sure that at least one edge is
straight. To check the edge of the board you may use a flat surface such as a
workbench or your table saw surface.
Rip all boards to a width of 5" of less. It is recommended not to glue together
boards that have a width greater than 5". This means, if you have a board that
measures 8" in width, cut it in half. The reasoning behind this is that wider
boards have more chance to cup or twists than smaller boards. If you cut a
wider board in half, you have reduced the continuity in the wood grain;
therefore the two pieces will absorb moisture at a different rate. Note that it
is not necessary for all the pieces to have the same width.
The boards should be marked and ready to be glued. Larger panels will require
long pipe clamps. When building larger panels, like a tabletop, it is best to
start by making several smaller panels and then assemble these to form the
larger panel. Using dowels or biscuits
to reinforce the joints is not required but it does help in aligning the boards
during the gluing phase. Flip the
boards on their edge and apply glue on the boards you want to join together. You
should limit yourself to about 5 boards per panel. Once the glue is applied to
the edge of the boards, lay them down and clamp them together, good side up. The
clamps need to be spread equally among the panel. Do not apply too much
pressure and watch for cupping that might result from tightening the clamp. The
pressure must be consistent on each clamp and some glue should squeeze out.
Wait about 15 minutes and use a scrap piece of wood to remove the excess glue.
Follow up with a damp cloth to remove the rest of the glue. Wait for the glue
to dry and proceed to the next of panel. Although the glue may attain 90% of it
strength in the first 4 hours, you should wait at least 24 hours for good
results. Since all the board joints have absorbed moisture from the glue, wait
the full 24 hours before doing any sanding. This allows sufficient time for the
joints to reach moisture equilibrium. Repeat until you have enough panels to
complete the panel's required length.
Once the glue on each panel has dried, trim each panel to the required width.
Lay down all the individual panels side by side and measure the total length.
Trim one or more panels until you reach the required length. Apply glue to the
edges of the individual panels and clamp them with long pipe clamps. Remove
excess glue and let dry.
At this point you have a complete laminated panel. It is time to sand the
surface with an orbital or a belt sander using 80 grit sandpaper. If your
panel is small enough, you may use your planer to level the surface. Do not
apply too much pressure or stay in one place too long. Use a square edge to
verify the surface flatness by checking the gap between the ruler edge and the
panel top. Smoothing the top is a time consuming process and in order to
achieve good results, do not rush through this step.