Top Flite TOPA0905 - Manual (Page 33)

hide the mufflers completely inside of the engine, be
sure you allow for an air exhaust area of at least 6 sq.
in. [.387 sq. dm.]. This is required for engine cooling
due to the tight fit of the cowl to the fuselage.
Install the Radio System
❏
1. Cut a piece of 1/4" foam 4" x 5" [102mm x 127mm]
and place it in the receiver/battery compartment.
❏
2. Locate the .074 x 36" [914mm] pushrod wires.
From the back of the fuselage, slide them into the
plastic tubes for the elevator and the rudder. Use the
wires as your guide for positioning the servos. Install
the servos using the same procedure used for the
other servos, mounting them onto the servo rails.
Install the servo arms onto the servos as shown.
❏
3. Remove the wires from the fuselage. On the
threaded end of one of the wires install a 4-40 nut
and a 4-40 threaded metal clevis approximately 20
turns. Slide the wire into the plastic tube for the
rudder and attach the clevis to the nylon torque link
on the rudder control wire. Center the rudder.
❏
4. Mark the wire where it lines up with the end of
the clevis. Cut the wire on that line.
❏
5. Remove the wire from the tube. Remove the
threaded metal clevis and the nut you previously
installed onto the wire. Solder a 4-40 solder clevis
onto the wire, aligning the wire and the clevis where
they were when you cut the wire.
HOW TO SOLDER
❏
A. Use denatured alcohol or other solvent to
thoroughly clean the pushrod. Roughen the end of
the pushrod with coarse sandpaper where it is to
be soldered.
❏
B. Apply a few drops of soldering flux to the end
of the pushrod, and then use a soldering iron or a
torch to heat it. “Tin” the heated area with silver
solder (GPMR8070) by applying the solder to the
end. The heat of the pushrod should melt the
solder—not the flame of the torch or soldering iron—
thus allowing the solder to flow. The end of the wire
should be coated with solder all the way around.
❏
C. Place the clevis on the end of the pushrod. Add
another drop of flux, then heat and add solder. The
same as before, the heat of the parts being soldered
should melt the solder, thus allowing it to flow. Allow
the joint to naturally cool without disturbing. Avoid
excess blobs, but make certain the joint is thoroughly
soldered. The solder should be shiny, not rough. If
necessary, reheat the joint and allow to cool.
❏
D. Immediately after the solder has solidified, but
while it is still hot, use a cloth to quickly wipe off the flux
before it hardens. Important: After the joint cools, coat
with oil to prevent rust. Note: Do not use the acid flux
that comes with silver solder for electrical soldering.
This is what a properly soldered clevis looks like—
shiny solder with good flow, no blobs, flux removed.
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