4-STAR 54 EG ARF

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on the top surface of the plywood battery tray, to make sure the
battery pack will not move around during aerobatics.
❑ 35) Mount the cowling on the fuselage with the four M3 x 10mm
Screws provided. Notice that the holes for the four cowl mounting
screws are already pre-drilled in the cowling - two on each side.
a) First test fit the cowling in place on the fuselage. As you
pass it over the motor, make sure all the wires are out of the way.
Carefully adjust the exact position of the cowling. Make sure you
have adequate clearance between the front of the cowl and the
back of the propeller, and that the prop shaft is centered in the
hole. Use a low tack tape to hold the cowling securely in place
for the next step.
b) Use a 5/64" or #45 bit to drill a pilot hole for the top left cowl
mounting screw. Center the drill in the hole in the cowling and
drill into the fuselage side. Install an M3 x 10mm screw in the pilot
hole - do not over-tighten the screw.
c) Recheck the position of the cowling and make any adjust-
ments needed to get it back in perfect position, securing the tape
to hold it in place.
d) Now drill another pilot hole for the upper screw on the other
side of the cowling. Install the screw.
e) Repeat this process to install the two bottom cowl mounting
screws. Remove all the tape.
❑ 36) COOLING IS IMPORTANT!
With a fully cowled motor, it is very important to make sure your
power system is getting proper cooling. Air flowing into the front
of the cowling must have a place to exit the cowl. In fact it’s best
to have more air exit area
than inlet area to create a positive air
flow through the cowling - an actual suction effect - drawing the
heated air out of the cowling so that more cool air can come in.
This positive air flow keeps your motor running cool. We recom-
mend that you make a simple opening at the bottom rear edge of
the cowling as shown in the next photo, to provide additional air
exit area. The exact dimensions are not critical.
Note: A Dremel® Tool, or similar powered rotary hand-tool, with
an assortment of sanding bits is without a doubt the best tool to
use for making cutout in the fiberglass cowling. However, if you
do not have access to such a power tool, you can cut the opening
with a drill, a hobby knife, and a sanding block - by first drilling a
series of almost touching holes inside the pattern lines (1/8” dia.
works well); then using the knife to cut through the connecting ma-
terial between each hole; and finally finishing the edges of the
opening with the file or a sanding block.
Additional Cooling Options:
In addition to making an opening at
the bottom rear edge of the cowling, you may decide after test fly-
ing that your ESC or battery pack could use some additional cool-
ing. We have not yet found that to be necessary with our
prototype 4-STAR 54, but it could happen in some cases with dif-
ferent motors, props, etc. If you need more cooling air flowing
over the ESC and battery, here are a couple good options.
Option #1) To get more air flowing into the fuselage, you can
open another hole in the fuselage firewall. Near the bottom of the
firewall, below the motor mount box, you will find an oval shape
cut into the thick plywood firewall. This oval is laser cut almost
completely through the firewall, and it is easy to finish the cut and
remove the oval, which will allow air to flow directly over the ESC.
Option #2) If you need more air flowing out of the fuselage,
make an air exit hole in the bottom rear of the fuselage, back near
the tail, as shown here. Simply remove the covering over the hole
already in the structure.
❑ 37) Mount a suitable propeller (not furnished) on your motor.
Be sure to balance the propeller before installation.