Chess Piece Mandrel for Lathe (MT2 taper)

thingiverse

I'm printing the 4d Staunton Chess Set. To achieve smooth, even surfaces on my chess pieces before painting, I created an expanding mandrel designed for use with my lathe. The mandrel fits snugly inside the 3/4" recess in the bottom of each piece and is secured by tightening a nut located at the rear. This device features an #2 Morse Taper (MT2) and can be used on any lathe or drill equipped with an MT2 taper. To assemble the expanding mandrel, you'll need four inches of 1/4"x20tpi threaded rod and a matching 1/4"x20tpi nut. The inner mandrel piece is then attached to the end of the threaded rod using epoxy. Once this is complete, the inner mandrel is inserted into the outer mandrel, followed by the nut at the rear. It's worth noting that using steel wool for sanding is not recommended, as I've personally experienced its drawbacks when attempting to buff a chess piece with it – the result was a melted and deformed top. You should also keep your lathe speed low, ideally below 1,000 RPM. This will help prevent excessive runout and ensure that your pieces are properly secured during the sanding process. If you don't have access to a lathe, an alternative solution is possible: by cutting 1.5" off the back of the outer mandrel and attaching it to a drill chuck, you can use the excess threaded rod to spin the mandrel. While this method may not offer the same level of torque as using a lathe, it should be sufficient for light sanding tasks. I designed the expanding mandrel in Autodesk Inventor, and I've included the .ipt files if you'd like to modify them.