When the time comes
to disassemble the
resist the urge to
bend the fuselage or
pull the pieces apart.
This could dent the
fuselage. Pulling a
fine string in between
the sections will
upset the bonds and
leave the sections
different colors to identify left from right
and top from bottom. Numbering the
segments on the forward edge, front to
back, establishes their order when it’s
time to assemble them.
The sections have to be broken apart
to cut the centers from them. Simply
pulling the sections apart will dent the
outer surface, so I employ a fine fishing
line such as spider wire to do the job.
The line is held taut like dental floss and
pushed in between the segments until
it reaches the tack bond. The fuselage is
flipped and the line is pulled up through
the bonds to upset them.
Now is your chance to record your patterns for future use.
While holding the section with the numbered side against a
sheet of card stock, trace the section’s outline. Don’t forget
to mark the reference lines and number the patterns. This is
a must if you are building parts that you will need to repeat,
such as floats or nacelles for multiengine models.
The next step is to cut the centers from the sections to
make the fuselage hollow. Because many of the sections will
have tapered shapes, you have to mark the smallest end for
cutting. A fuselage wall thickness of 1/2 to 1 inch is sufficient
for average-size models.
The skin can be thinner, but you will have to plan ahead to
make stress points thicker to support landing gear and wing
attachment. Individually cutting the sections on a scroll saw
will produce an interior that resembles stairsteps. This uneven
surface does not present a problem aside from a slight weight
To remove the steps, each section is used as a pattern for the
one before it. The excess material is now sanded to match its
Another method is to use a hot wire to cut the centers from
the sections. This is a preferred course to take because several
sections can be cut at the same time with smooth results. Hot
wire-cutting patterns are made for both ends of the segment
group and attached with double-sided tape. The hot wire is
threaded through a hole made in the group and attached to
42 Model Aviation JULY 2017 www.ModelAviation.com