Great Planes Super Sportster 40 MkII Kit - GPMA0205 - Manual (Page 28)

MONOKOTING TECHNIQUE
You can practically eliminate MonoKote wrinkles that
sometimes occur when the model is left out in the sun or
in the back of your car by following this technique used in
the Great Planes model shop:
A Cover your sealing iron with a Top Rite Hot Sock and
turn the heat about 3/4 of the way to the high setting.
B Say we are going to cover the Stab cut a piece of
MonoKote film about 2" larger all around Strip off the
backing and position the film Tack the film down smack
dab in the middle of the Stab.
C. Pull (as in stretch) the film toward the tip, sealing it to
the balsa from the center out to the tip Work out any
wrinkles and air pockets as you proceed with a
combination of circular and back and forth motion.
D Do the same procedure working the opposite
direction from the center.
E Pull and seal diagonally toward the four corners,
always starting from the center The trick is to shrink out
any wrinkles before you seal the film tothe surface.
F. Use a heat gun to heat and stretch the film around
curved surfaces like the stab and rudder tips, while pulling
on the excess material You may need to pull hard to get
out all of the wrinkles, so wear a glove if you need to.
Follow-up the heat gun with your sealing iron to secure
the bond.
The idea behind this approach (which can be applied to
any part of the model) is to pre-stretch the MonoKote as
it's applied, and remove the air pockets that can expand
later which cause the sags and wrinkles
When covering areas that involve sharp junctions, like the
tail section, cut narrow strips (3/8" to 1/2") and apply them
in the corners before covering the major surfaces The
larger pieces of MonoKote will overlap and capture these
smaller pieces This technique also bypasses the need to
cut the MonoKote in these areas after it has been applied
DO NOT, under any circumstances, attempt to cut the
covering material after it has been applied to the fin
and stab, except around the leading and trailing edges
and the tip. Modelers who do this often cut through the
covering and part-way into the balsa stab This can weaken
the stab to the point where it may fail in flight'
1. Tail Junction Strips as described above
2. Rudder left and right side
3 Bottom of elevators
4. Top of elevators
5. Stab bottom
6 Stab top
7. Fin left and right side
8. Fuse bottom
9 Fuse sides
10 Fuse top
11. Ends of ailerons
12 Bottom of ailerons
13. Top of ailerons
14. TE surfaces of wing and belly pan
15 Bottom of left wing panel
16 Bottom of right wing panel
17 Sides and bottom of belly pan
18 Top of left wing panel (overlap covering 1/4" at wing LE
and wing centerline)
19 Top of right wing panel (overlap covering 1/4" at the
LEand wing centerline)
Paints used on the prototype:
We used K & B Super Poxy primer and color coat.
Surface Preparation:
Mix equal parts of K & B primer, hardener, and thinner,
then stir the mixture well Spray the wheel pants with a
thin coat of primer Add a second coat of primer to areas
that need it Its best to allow the primer to dry overnight
before sanding Wet sand the primer with 320 and 400 grit
sandpaper using a sanding block where possible Most of
the primer should be sanded off
Color Application:
The wheel pants were sprayed with K & B Super Poxy We
custom mixed the paint to match the Red MonoKote by
adding a little #8116 Yellow to their standard #8113 Red
color Keep a swatch of MonoKote handy to test and
compare the color on a regular basis All paints dry slightly
darker than they appear while wet Spray on the color coat
when satisfied with the match.
28