There are several easy ways of making a propeller. Here is one of them.
|Cut two blades from a yoghurt container, coffee cup, etc.. If you cut the blades in an angle of 15 degrees the pitch of the blade will be less at the tip, as it should be.|
|Take a piece of 1/16 square and pierce a pin hole dioganally through the middle.|
Glue the blades to the balsa. Because of the curve in the blade each blade will touch the balsa in only two spots. Make sure that the portion of the blade closest to the middle of the prop fits well to the balsa so that part of the blade has a 45 degree incidence.
You can determine the actual pitch by using Paul Bradley's "Pitch Gage".