This parts tumbler was easy to build but it still does a great job of rounding rough edges and polishing the surfaces of parts cut with a CNC machine. You can see that it mounts in a bench vise, and the cooling fans have a magnet which holds the tray in place on the anvil portion of that tool. Since you’re not constantly tumbling parts this makes it very easy to store the unit between uses.
[Neo7CNC] mounted the wooden tumbler plate directly to the motor shaft. This is done with the help of some aluminum stock which bolts to the round wooden plate, and has a hole and set screw for the motor’s keyed shaft. There are four wooden dowels which cradle the plastic coffee jug where the parts go. As a first test he used zinc BB’s that he already had lying around, but has put some steel ball medium on order for future projects.
It’s certainly more robust and powerful than the LEGO ball mill we saw a while ago. Just be careful with motor. Even at a lowly 60 RPM it ended up getting really hot and that’s the reason there’s a heat sink and fan unit included in the build. See it in action after the break.