Rustik is another of my
"on the bench" designs. It is a fairly standard planform model having a
4:1 aspect ratio wing with a 15% symmetrical airfoil.
Typically when I am scratch building , I build the
wing first and then build
a fuselage and tail to match. Such was the case with Rustik.
The entire model is built from wood including the empennage control horns and
landing gear. In fact, I even made the tail wheel mount from hardwood.
In retrospect, I should have made the aileron and flap
horns from wood as well, but I did not realize I was going to use wood horns at all
until after the wing was built. Mike still hassles me about not using
wood horns on the wing, but there is not much I can do at this point. I did
not design any type of reinforcement into the structure to glue wood horns to
I would have to build all new flaps.
qualities came second to aesthetics. Therefore the airframe is not as light
as it could be, but it is as light as it can be for what it is. This same design
(aerodynamically) could easily come in around 4 lbs instead of 4-3/4 lbs by
building trussed fuselage sides instead of using slabs, eliminating the inlays, building the wing as a D-tube,
using strip ailerons with 2 servos instead of 4 and using a
carbon fiber landing gear.
I did everything I could to ensure this model would not be
a lead-sled. Contest balsa is used wherever possible, the
ribs have large
areas removed from them and pull-pull controls are used rather than pushrods.
The pull-pulls are .020 music wire. I made the fittings from threaded rod
and used a wire bit to drill small holes to put the wires through.
All tail surfaces are
built up and incredibly light and strong. In fact, they are lighter than a
thinner sheet surface would be.
The stabilizer is built using about 20 1/16" contest balsa ribs with 1/8" spars and
It is sheeted with 1/32" balsa and has solid wood tips.
Prior to finishing, the completed stabilizer weighed 2.1 ounces with
Hinge Points (5 total) and the control horn.
The vertical stabilizer is also built up, but because of the inlays, it
requires 1/16" sheeting. After the internal structure was built, the
fin and rudder were joined together using wood dowels in place of the Hinge Points.
Three laminations of 1/32" balsa are wrapped around the perimeter so that
the sheeting has something to glue to. The fin and rudder are
sheeted as a unit to ensure the inlays would remain in alignment.
I could not find a
reliable way to jig the fin structure on the board while the sheeting was drying because of the way
it is built. Instead I sheeted both sides simultaneously
while taking care not to build in a warp.
After the sheeting dried
and the edge was sanded, the fin and rudder were separated. Each piece has
three more laminations of 1/32" balsa to create the edge.
At this point all the major structures were done, but the finish was
difficult due to the weather. Believe it or not, it even gets too cold in
Florida to spray paint. I ended up waiting for the best weather I thought
I would get and sprayed when it was 55°.
The finish orange-peeled. A lot of sanding got it back to something I
could work with and then it orange-peeled again. I realized that I would
have to wait for better weather, so I gave it one last light coat to ensure I
hadn't missed anything.
I knew I could live with it (for now) because the finish is fuel proof.
I can sand the paint at any point in the future, do a little masking over
switches and such, and then respray.