powder mixed with another solution. It is a
water-resistant glue that works well on hardwoods.
It is a cold-working glue that sets within 24 hours at
room temperature (70F). Urea resin glues set and
Vinyl resin glue is a synthetic thermoplastic
white liquid. It requires no mixing or heating
before use. This glue comes ready to use and can
be applied at temperatures above 50F. The initial
setting of the glue takes less than 30 minutes. A
strong bond will occur in less than 1 hour for
ordinary work. In addition, this glue is compounded
to reduce wear on cutting tools. It also has a glue
line that is practically colorless. For general
construction, vinyl resin glue has replaced all glues
that require heating, cooking, or mixing.
Figure 3-45.--Standard table construction.
Pointers on Using Glue
Tabletops usually fasten to the upper rails (fig.
3-45) by one of the six standard methods shown in
Prepare and use each type of glue in a specific
figure 3-46. You will probably use the cleat more
manner. Instructions and safety precautions are
than any of the others. Fasten the cleat screws to
always given on the label of the container, or on the
the rail first so it is about 1/16 inch below flush.
MSDS for the glue. You should study these
Then, the screws going into the top will pull the top
carefully before trying to use any glue. Certain
down tight and snug.
rules should be followed in the application of all
glues.
FASTENING MATERIALS
The wood should be room temperature (70F).
If the wood is cold, the glue next to the wood chills
Many kinds of fasteners hold wood together.
and sets before it has penetrated the pores of the
These include glue, nails, screws, bolts, and special
joint. If the wood is hot, the water in the wood will
fasteners.
expel, causing the joint to warp. Glues give best
results when the wood is at room temperature.
TYPES OF GLUE
Squeeze or rub excess glue out of a joint before
The two most commonly used glues in today's
applying pressure. Always apply pressure as quickly
pattern shop are urea resin glue and vinyl resin
as possible after spreading the glue. This prevents
(white) glue.
the glue from setting before the excess can be
squeezed out. The greater the pressure applied, the
Urea resin glue is a synthetic compound that
stronger the joint will be.
comes either in a powder mixed with water or a
NOTE: Do not apply so much pressure that the
wood crushes.
If possible, the pressure should be at least 100
psi. Squeezing out too much glue is impossible.
Clamps alone produce this pressure, but they do not
distribute the pressure evenly. To get a joint with
maximum strength, you should use plates between
the clamps and the wood.
Figure 3-46.--Securing rails to tabletops.
3-30