you’ve ever wondered how to build a straight fuselage
from scratch with only a few basic tools, I can assure you that it’s
easier than it sounds.
One of my favorite planes is the RCM
Don’t let the name fool you. Just because it’s called the Basic Trainer
doesn’t mean that you have to be a beginner to enjoy it. This is a
four-function airplane with ailerons, and it’s pretty good looking,
too. Everybody really ought to build one of these. The flat fuselage
top and bottom make it even easier to build it straight
without a jig.
After you get the fuselage sides and bulkheads cut out,
four pieces together to make a basic box. Measure the diagonal distance
from corner to corner in the cabin/radio compartment. First measure one
Then the other way....
If your two measurements are the same, then your
If not, squash the fuselage diagonally until the two dimensions match.
You may have to put a squeeze on it hard enough to crack the glue, then
reglue it in the right position.
After you have the radio compartment square, put the
bottom of the fuselage, only in the radio compartment area. Then draw a
centerline on the bottom of the plane using a straight edge.
At this point you pull the tail together. I've
that if you do the nose first it's easier to get it crooked, and it
will have a severe effect on the tail. But if you do the tail
first, it's easy to get it straight. Just use the line on the
bottom of the fuselage to line up the tail joint. When you pull
the tail together and the line points right at
the joint, it’s straight. I like to use a long straight edge instead of
my eyeball for greater accuracy
When you’re gluing the tailpost, in addition to being
also has to be vertical. Glue just the tip of one corner and hold the
fuselage in front of you with the tail pointing at your eye. You should
be able to tell if the tailpost is parallel to the vertical sides of
the fuselage. Shift it until everything is straight, and then glue the
After you get the tailpost joint worked out, go ahead
bottom of the tail section. Whenever I buy balsa wood, I always get
some flat sheets and some warped ones. Save the flat ones for wing
sheeting and fuselage sides, and use the warped stuff for cutting up
into little pieces for fuselage planking. Here’s a warped sheet
of 1/16″ balsa, in case you wanted to see one.
Only after you get the aft planking done, install the firewall.
a ruler to line it up with the centerline. A thin flexible metal ruler
will allow you to follow the curve of the fuselage bottom and land on
the mark on the firewall.
After you get the firewall lined up on the centerline, epoxy it and
clamp it in place. After you have that done, attach the chin sheeting.
Now you have a straight fuselage, and you didn’t even need a jig.