I’ve been working on my balsa airplane and I’m almost finished! I still have quite a bit of ‘finishing touches’ to do, but I’m getting pretty close to flying it. One thing I built for the plane was a steerable tail-wheel. The steerable tail-wheel was easier than I thought it’d be, and I think it looks kind of cool.
For the tail wheel itself I bought a Sullivan 1/2″ tail wheel from the hobby shop. At the hobby shop they sold steerable tail wheel brackets, but I didn’t see it necessary to buy one when I had the stuff at home to build my own.
To build the bracket I cut a piece of brass about 1/4″ wide and about 1″ long. It’s probably 1/32″ or so thick. I took this piece of brass, and after smoothing the edges with a file and sandpaper, I bent one end of it up a little. I then drilled three holes in the brass. One hole for the wire that will be the wheel axel and two holes for screws to mount the brass to the airplane. I then attached this bracket to the plane with some small wood screws. I then began working on the wheel axel.
The rest of the steerable tail wheel assembly pretty much consists of music wire. The commercial versions of a tail wheel have a spring coil in the wire to absorb shock on the ‘less-than-perfect’ landings. I knew I needed to incorporate one of them :P. The first thing I did was began working on the spring. I used a drill and a drillbit to make the spring coil. (The method on how to do this is too long to describe here. If everything goes as planned I’ll show you how to coil your own spring next week…or the week after…) After I had finished the spring coil I bent the wire to accept the tail wheel. I had to bend it kind of funky so the wheel would be in the center. I couldn’t just make a simple 90 degree bend or the wheel would be on one side of the wire – not the center. After doing this, I slid the wheel on (the wheel did have to be drilled out a little to accept the size of wire I was using) and then I slid on a wheel retaining collar purchased from the hobby shop. When I was putting the wheel collar on, I put some clear finger nail polish on the set-screw as a type of poor man’s Loctite thread locker. This is so I don’t lose my wheel mid-flight. After that I did some more bending on the wire so it would go through the brass bracket and then curve around the edge of my rudder. It is important to make sure the wheel is directly below the rudder’s hinge line to give the best rotation. On the very end of the wire I made a bend so about 1/8″ of the wire actually goes into the wooden rudder.
To secure the wire to the rudder I used thread and superglue. I drilled five small holes along the rudder edge, and using an embroidery needle with 3 doubled up strands of cotton thread (which created 6 ‘strands’), I sewed around the wire and through the rudder. I then doused the thing in thin CA (superglue) to make it strong. I recommend thin CA because it wicks up into all the cotton strands and balsa wood and makes it extremely strong.
So that’s it. Sorry I don’t have any mid-build pics. I guess I got too caught up in building that I didn’t take any pictures. . .
