Very simple yet accurate Magnetic Prop Balancer

thingiverse

This is a easy to print prop balancer that uses magnets. It's best in PLA as the arms work better when stiffer. It's parametric so any size prop can be handled and you can use any round magnets you have. I recommend 5mm round ones though, 5-10mm long. Instructions For the default setup in this model you need two 5mm dia rod magnets, 10mm long. If your mags are shorter, adjust, it works fine with 5mm dia 5mm long ones too. Using M6 umbraco head screws will fit 5mm round magnets very well. After printing, drill out the magnet hole if it's too tight and thread the two screw holes. Then insert a screw in clamp section and prepare a screw with magnet for balancer side by gluing a magnet into the umbraco head. Push the other magnet into the magnet cup opposing the screw and you're done. The balancer shaft/cone assy can be a cheap one from hobbyking or if you have a lathe you can make your own. In use, make sure to adjust the grip so the magnets both pull as much as possible on the shaft without them both touching it. This will give minimum friction.