Great Planes F-16 Falcon EDF ARF - GPMA1801 - Manual (Page 9)

9
❏
1. Test fi t the fan unit into the fuselage. Guide the fan unit
aft until the cone adapter mates up with the tail cone already
in the fuselage. The cone adapter should key around the
inside of the front of the tail cone. Do not proceed until you
are comfortable that the fan unit is properly seated into the
tail cone. Rotate the fan unit until the motor wire cutout is
centered in the top of the fuselage just under the fi n. The motor
wires should also be in the top of the fuselage. With the fan
unit in position, fi t the motor lead wires through the opening
at the top of the plywood former and fi t the former around
the fan unit. You must hold the fan unit against the tail cone
while doing this to prevent the cone adapter from separating
from the tail cone.
❏
2. Now that you’ve confi rmed how the fan unit fi ts, remove
it and the plywood former from the fuselage. Apply a bead
of 30-minute epoxy mixed with Microballoons fi ller (4:1 ratio)
around the cone adapter and around the outside of the cone
in the fuselage. Reinstall the unit into the fuselage, making
sure the cone adapter is properly engaged with the front
of the cone. Carefully reinstall the plywood former around
the fan (without glue), keeping the cone adapter in the tail
cone. Wipe away excess epoxy by reaching down in through
the back of the tail cone with your fi nger. Allow the epoxy to
harden undisturbed. Hint: Add a thin fi lm of petroleum jelly to
the motor extension wires at the aft end of the cone adapter
to keep excess epoxy from sticking to the wires.
The next three steps require you to apply a mixture of epoxy
and Microballoons to create fi llets around the plywood
former, front housing fl ange, and fi n cover. The fi llets can be
applied with an epoxy stick or something similar. However,
a hobby syringe (HCAR3785) is recommended. Using a
syringe will apply the mixture only where you want it and is
easier to use when having to reach into the duct channel.
In addition, the smooth fi llets created using the syringe will
be less likely to disrupt incoming air which could slightly
reduce fan performance.
If you choose to use a syringe to complete the following steps,
read through them fi rst and prepare the parts before you make
your epoxy and Microballoons mixture by dry fi tting them in
place. When satisfi ed with the parts fi t, make enough epoxy/
Microballoons mixture to fi ll the syringe. Enlarge the opening
in the syringe by cutting off a portion of the tip. Complete the
next three steps in order. Be aware that excess epoxy will
have a tendency to sag. Increasing the ratio of Microballoons
to epoxy will make the mixture thicker and less likely to sag,
but more diffi cult to apply and may weaken the bond.