A bead of glue is applied to the outer surface of the inner stick and the
outer stick is pulled around and taped in place. Be sure to keep the edges
of the sticks aligned evenly as the outer stick is pulled around the form. The bow can be either air dried or placed in a microwave to dry.
With the wood thoroughly dried, the bow is removed from the pattern
and the remaining bows are laid up using the same pattern.
The completed bows are trimmed to fit and glued into place on the appropriate assembly.
and pull the outer stick around the form, taking care to ensure
that the two sticks are properly aligned along the edges and
tape the outer stick in place.
Drying the Bow
There are a couple of ways to dry the bow. You can leave it
on the form overnight to thoroughly dry, or you can place it in
a microwave and cook it on high for 8 to 10 seconds at a time
until it’s completely dry. It usually takes three or four cycles.
Larger bows, such as wingtips, can stay in the microwave
slightly longer, but if left too long the foam board form will
blister and separate and you end up having to make a new
one for the second bow. After the wood has thoroughly dried,
remove the tape and remove the bow from the form. Now
make the rest of the bows.
If you want to make the bows even stiffer, you can place a
layer of .007-inch carbon fiber or 1/64-inch plywood between
each of the balsa sticks. It is best to make up all of the bowed
outlines before model assembly begins so they will be handy
when the time comes to glue them in place.
That’s all there is to it. As with any modeling skill, there is a
learning curve, but once you learn how to best select the wood,
and how much pressure is needed to press the wood neatly
around the form, you’ll be able to make a full set of bows in no
time at all.
Elmer’s Products Inc.
37 Model Aviation JULY 2017 www.ModelAviation.com sponsored by HOW-TO issue