Construction Manual
www.oldschoolmodels.com
Page 11
Step 80 - Final airframe assembly (trimming)
One last bit of housekeeping
before the wings can be
attached. Cut open the slot in
the fuselage where the dihedral
brace will be inserted. You’ll
only be cutting through the
1/4” balsa interior.
Also trim out the excess 1/4”
that protrudes into the tank/
battery area. This is left there on purpose to strengthen the parts
during laser cutting, but can now be cut away as it will interfere
when joining the wings to the fuselage.
Step 81 - Final airframe assembly (dihedral brace)
Locate D2 from LP2 and four
D1s from BP1 and BP2.
Note that on the etched side
of D2 there are two lines in
the center. When attaching
the D1s, make sure they line
up with this line. Position two
D1s as shown and glue to
D2. Roll the piece over and glue the remaining two D1s to the
same end.
Step 82 - Final airframe assembly (dihedral brace)
When the glue has cured
from the last step, it’s time
to start test fitting this piece
into one of the wing halves.
You’ll need to sand a bit,
round a bit and take your
time to make sure that the
brace will push smoothly into the pocket in the wing.
When satisfied with the fit, mix enough epoxy to glue the brace
into the wing half and let cure.
Step 83 - Final airframe assembly (attach first wing half)
It’s time to test fit the wing half to the fuselage. You’ll see that when
pushed into place, the anti-rotation pin will fit into the pre-cut hole
in R1. Also the TR piece will notch into the back of the firewall,
resting on the cutout for the tank/battery. Sand as necessary to
ensure the wing is 90° to the fuselage. When satisfied with the fit
and alignment, remove the wing and mix a bit more epoxy. This
time you’ll need enough to coat R1 completely. With the epoxy in
place, slide the wing in position and allow to cure.
Step 84 - Final airframe assembly (D1s)
Locate the remaining
four D1s from BP1 and
BP2.
Glue these on each
side of the dihedral
brace protruding from
the other side of the
fuselage. Once dry,
sand them, and test
fit them into the other
Step 76 - Wheel Pants (P1)
Remove the axle shafts from the
wheel pant assembly. Now locate
two of the P1s from BP2. Carefully
glue one to each side of the wheel
pant to complete the assembly.
Now go back to step 73 and
repeat the process to form the
second wheel pant.
Step 77 - Sanding (airframe)
At this point you
should have 10 large
sub-assemblies and
the radio hatch - just
as pictured to the
right.
Now is the time to
get quite familiar with
the sanding tools of
your choice.
Take the time to
preform a good sanding, rounding the leading edge and blending
them into the wingtips. Round the leading edge of the stab and
vertical fin, as well as the trailing edges of the elevator and rudder.
Smooth out the edges of the fuselage and the trailing edge of the
wing. Sand bevels into the leading edge of the ailerons, elevator
and rudder.
Also make sure that the root rib (R1) is flat on both wing halves.
Make sure that any protruding sheeting, spars, leading and trailing
edge stock is sanded flush with the rib.
But don’t sand/damage the TR pieces. those should be left alone
as they are.
Step 78 - Sanding (wheelpants)
Also it’s time to round
off the wheelpants.
Actually, some folks
just preferred to leave
them in more a of a
block shape, but it’s up
to you.
If you do round them
like we have, make a
note of where the opening is on the inside so you don’t sand into
that area and cause yourself some problems.
Here’s a photo of a before and after of our prototype’s pants.
Step 79 - Final airframe assembly (anti-rotation pin)
From the remainder of the 1/4”
dowel, cut a piece that’s roughly an
1-1/2” long. Round off the edges
and gently pound it into the hole
in the fuselage so that it sticks
out equally on both sides of the
fuselage.
No need to glue this in place right
now as the friction fit should be more than adequate.
