.
We’ve used and can recommend NELSON HOBBY SPECIALTIES water-based two-part EPOXY PRIMER for the wing
struts and landing gear. Brush or spray a coat of the epoxy primer over the entire part. When dry, sand well. Put on
another coat of epoxy primer, let dry, and sand again until the surface of the wood and fiberglassed area are smooth.
Then, we sprayed two coats of SIG CUB YELLOW SUPERCOAT DOPE over the primer. The SIG CUB YELLOW DOPE
is a pretty good color match to the SOLARTEX CUB YELLOW FABRIC covering that we used.
Cowling
157.
Position the cowling over the F-1 cross-section on the plan (sheet 1) and mark
the location of the center line and thrust line on the outside of the cowl. Then,
use a large triangle to transfer the marks to the top of the cowling.
158a.
With a Dremel® tool or hobby knife, cut an opening in the front of the cowling
large enough for the engine’s prop shaft and drive washer to fit through. Locate
this hole according to the thrust line marks that you made on the cowling in the
previous step.
b.
Cut out the two oval shaped air intake holes in the front of the cowling, right
below the prop shaft opening. Refer to the fuselage front view plan for the exact
size and location.
c.
Cut a 3/4"x1" hole in the "chin" of the cowling where the molded plastic air cleaner will go.
d.
Make any necessary openings in the cowling to fit your particular engine, needle
valve, etc.
e.
An opening must be made in the bottom rear of the cowling to allow the engine
cooling air to properly flow through and exit the cowling. This is absolutely
necessary for proper cooling! Without an adaquete exit air opening, your engine
may overheat and quit. There’s an old rule of thumb that says you should have
1-1/2 times are many square inches of exit area than intake area in your cowling.
That ratio will keep a constant stream of fresh, cool air moving through the
cowling. Inadaquete exit space can cause heated air to be trapped inside the
cowl, which can cause overheating and engine failure. This picture shows the
size of exit air opening we have at the bottom of our Cub cowlings.
159a.
Cut four 3/8" sq. x5/8" long basswood cowl mount blocks. Epoxy the blocks along the edges of the firewall, two on each
side, approximately where shown in the photos and plans.
Note: You can adjust the exact location of the cowl mount blocks to suit your individual engine installation. Just make sure
the outsides of the cowl mount blocks end up flush with the outside surface of the model.
b.
Tape the cowling in place on the fuselage. Line it up carefully in final position. Then, drill pilot holes with a 3/64" dia. bit
through the cowling and into the cowl mount blocks. Take the cowling off and open up the holes in the cowl large enough
to pass the #2 x3/8" Sheet Metal Screws provided. Mount the cowling to the fuselage with the screws.
160.
The fiberglass cowling has a paintable white jellcoat outer service. After sanding it with 360 grit sandpaper, you can paint
it with airplane dope or almost any other common epoxy or enamel model airplane paint.
Dummy Engine
A molded ABS plastic scale-like "dummy engine" is provided to make the nose of
your Cub look more realistic. The dummy engine is completely cosmetic. It
serves no structural or aerodynamic purpose. To use it or not is entirely up to
you. We use it on all our Cubs because it adds a lot of realism to the model.
161a.
Cut out the right and left molded plastic dummy engines. The cut lines are
molded right into the parts. The best procedure for trimming is to first rough out
the parts with a heavy-duty scissors or shears, leaving about 1/8" outside the
final cut line. Then, finish the edges by sanding it to final shape, checking the fit
of the part to the side of the cowling as you go.