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Finishing the Front End: All RTF aircraft are delivered with a loose, or uninstalled, propeller and spinner for safety purposes. Bolts might loosen during climate changes that occur during shipping, and that can be a safety hazard. If the propeller is uninstalled, leave it off for now. If it is installed, remove it by reversing the installation instructions.

    Remove the muffler. This is necessary because none of the RTFs use thread-locking compound, so the mufflers loosen in the first few flights.

    While the muffler is off, tighten whatever bolts hold the engine and engine mount in place. Do not remove the engine itself, especially if a clamp mount is used. Realigning the thrust angle can be difficult in such a mount. Just make sure the bolts are tight.

    Also while the muffler is off, check the throttle movement. With the throttle stick at high, positioned away from you, and with the throttle trim on high, the throttle barrel should be just fully open. If not, adjust the clevis by turning it until the barrel is fully opened.

    Leave the trim on high and lower the throttle stick all the way. The barrel should close until there is roughly a 1/16-inch opening. Lower the throttle trim lever all the way, and the barrel should just close completely. This small preflight check is easier to perform now because clevis adjustment is easiest without the muffler.

    Apply the removable type of thread-locking compound to the muffler holes and the mounting bolts. Coating just one side is seldom enough. With both covered, your muffler will be yours to keep forever. This beats combing the fields looking for it after every 20 flights. Install the muffler.

    Install the propeller using the correct-size box wrench. Today's powerful engines can start backward, putting extra stress on the prop nut's firmness. The small four-way tool that was popular years ago may not provide sufficient torque.

    All RTF spinners use small screws to mount the spinner cone to the backplate. Make sure the spinner cone rests fully into the backplate's groove before tightening these screws. The screws themselves are not powerful enough to "pull" the spinner cone into place if there is a misalignment. Tighten the screws firmly, but do not apply excessive force; they are just going into fragile plastic threads. Use a small hobby screwdriver for this task.

    It may be necessary to remove excess flashing from the spinner cutouts surrounding the propeller. Use a sharp #11 blade in a hobby knife to remove minute pieces one at a time. Recheck after each cut.

    If there is more than a 1/64-inch difference, preventing the spinner's mounting properly, chances are that the propeller is in the incorrect position on the backplate. Check this before cutting the spinners.

    Ensure that the nose wheel is pointed straight when the rudder is centered. If it is not, adjust it using the servo setscrew located inside the fuselage on the rudder-servo control arm. Retighten the setscrew once the nose wheel is straight.

    Attach the main landing gear using the supplied bolts. Test-roll the fuselage to make sure it goes straight. Make any steering adjustments required using the nose-wheel steering adjuster that I mentioned previously.  

Photo 7a  Photo 7b  Photo 8  Photo 9

Click on photo to view large image with caption

Mounting the Wing: All RTFs I know of—except for the Alpha 60 and the NexSTAR—use rubber bands to mount the wing. The NexSTAR uses a single, shock-mounted, rear nylon bolt and a plastic front pin. The Alpha 60 offers the choice of rubber bands or the traditional double rear nylon bolts threaded into preinstalled metal blind nuts. Two wooden dowels hold down the front end.

    If your aircraft uses rubber bands, carefully measure the fuselage width at the front and the rear of the wing. Make a pinhole—at the midpoint between the two sides—in the fuselage, just ahead of and behind the wing.

    When mounting the wing, align the center wing joint with the two pinholes. This centers the wing and helps keep the trim constant from one flying session to the next. This process is not required using wing bolts because trim and wing position remain constant with this system.

    If you are assembling the NexSTAR, make sure to attach the speed-control flaps with the six screws provided. Although they look ungainly, these slotted flaps make airspeed control during takeoff and landing much easier for the new pilot. Hangar 9 trainers use three-blade propellers for the same purpose.

    Additional modifications can be made to RTFs, but they are more to enhance performance than to increase durability. Items such as stronger nose gear, sealed control-surface gaps, wheel pants, and reinforced firewalls offer performance advantages, but they also start to take the "R" out of RTF. Since these modifications, and others, are also useful on ARFs, I'll cover them next month.  

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