[McKGyver] needed a few parts manufactured. Instead of going the normal route – finding friends with machine tools or paying a machine shop, he improvised a rudimentary metal lathe.
As much as we love 3D printers, they’re not the be-all, end-all solution for everything. Sometimes, you need to get a little dirty and do it the old-fashioned way. [McKGyver] needed a way to produce aluminum shaft couplers to join stepper motors to lead screws. A 1940s grinding wheel was used for the headstock. Since [McKGyver] only needed couplers of one size, he made a jig out of wood to attach the aluminum blanks to the spindle. A drill and a focuser from a photographic enlarger makes up the tailstock of the improvised lathe. The use of a camera focuser is pretty clever. Unless the equipment has been damaged, it’s guaranteed to move in a straight line. A small laser was used to align the drill.
The finished couplers were concentric to 0.005″. A ‘passable precision’ for his application, and a clever build that doesn’t involve moving a thousand pound South Bend lathe.