Rudimentary Metal Lathe
I needed a method of producing aluminum shaft couplers to join stepper motors to a lead screws. Unfortunately I didn't have access to a lathe at the time, so the only solution was to quickly build one.
Headstock: a cast iron grinding wheel from the 1940's
Tailstock: focusing apparatus from an industrial photographic enlarger.
I only needed to make couplers of one size, so I made a jig out of wood to attach the aluminum blanks to the spindle.
Note the red laser line used to bring the apparatus into alignment (along the centerline of the drill bit)
The finished couplers were concentric to within 0.005", passable precision for my application.