Buffer wheels. You need a grinder that has buffer wheels.
Bluing tanks. You'll minimally need four of them: degreaser, bluing, neutralizer and then a rinse tank.
Space. You need your buffer in a space that if you lose a piece and it goes orbital, it won't take out the fish tank, a window or damage your car. You also need it clear so you can find the orbital piece once it lands. You also need space for the tanks. Oh, you also need clean water that doesn't have any minerals because the minerals will affect the salts. You also need gas (or propane) with which to heat the tanks and a good concrete floor that is coated to prevent the salts from eating up the floor. You also need a central drainage hole for any liquids to run down into.
Vigilantibus et non dormientibus jura subveniunt. Molon Labe!