The Rebel KF Trainer Plane

By Donald Ferguson, Asst. Editor - RCScratchbuilders.com

The Rebel KF left the fingers like a dove leaving the hands of a magician. Its electric motor pulling her steadily skyward. Gaining altitude, she slowly banked to the left, as if wanting to look below. He was looking up, smiling, wishing he was flying beside her, darting, diving, soaring. Such freedom only known to birds has been man's desire for thousands of years.

Such is the case with the Rebel KF trainer. It relishes this freedom, it WANTS to fly, and you can make it happen all your own. You only need a few tools, some foam sheet material, and a desire to learn to fly. A desire to control the Rebel KF, make her go where you point her, to enjoy the pleasures of flight. To be like Ikarus.

To begin you will need a three channel radio system as a minumum to fly the Rebel KF trainer, which uses rudder, elevator, and throttle control. For power, the test plane used a Tower Pro 2408-21 brushless motor/ESC combo, using a stick mount. APC 8x3.8 slow fly prop provided the thrust.

Lets start this project with printing out the plans, and tracing them to the foam sheet material. I used Dow Blu Core fan fold foam, but you can use any sheet material you have that is 5 to 6 mm thick. Carefully cut out each piece with sharp hobby knife. An X-acto knife using a number eleven blade is prefered. Once all cut out, place the two fuselage halves on top the other and make sure they match up well. Trim as necessary. You can paint the parts to whatever scheme you desire, using foam-safe paint. I used Sharpie markers on my plane. Make sure you have proper ventilation though.

Next is to begin the puzzle of putting these parts together. Start with the motor stick mount (You will have to modify the motor mount system for different mount styles). Using a ruler, I marked two lines, half-inch apart, for the length of the foam (Figure 1).

These two lines are to help with the proper amount of right thrust as required when mounting motors to counter-act the torque of the spinning prop. I used popsickle sticks to mount the motor, but you can use any suitable stick that fits the square mount hole. I needed to add some packing tape to the end of the sticks to remove any slop when the sticks are inserted into the mount hole.

You can either glue the stick in the mount, or drill a small hole and twist in a small screw to keep the stick from coming out. This mount is now glued between the two lines drawn on the foam piece, making sure each end is pointing in opposite directions (Figure 2). This makes for proper right thrust (Figure 3).

Note that because the picture is viewing the motor mount from the bottom, it appears to the left. When mounted in the plane, it will be facing down, and therefore providing right thrust. Be sure to note this when gluing on the thrust mount!

Taking the fuselage sides, mark the lines where the two formers go, and the motor plate lines on the sides, using the plans as a guide. Next you bend where marked in the plans (Figures 4 and 5). I used a triangle-sided ruler, placing one of it's edges on the foam, to press a groove where the bend takes place.

You can carefully bend the lines over a square edge of a table if you want to. Do this for both the left and right halves. Now glue the formers in the correct spots, making sure they are squared-up. Finally, glue the motor mount plate on after this (Figure 6).

Mate the two sides together. Place the fuselage on it's bottom and glue the rear tips together, followed by gluing and pressing the halves together (Figure 7) aligning the formers to their corosponding lines. If done incorrectly, you may have a lop-sided fuselage.

Before gluing the bottom on, glue a landing gear strengthener inside the fuselage first (Figure 8).

The bottom is also bent as you did the sides (Figure 9), and glued. Trim the edges as necessary after the glue sets.