Other that the preposterous little job used in installing a fly cut in a tumbler I use my drill presses for drillig and the milling machine for milling.The milling machine has heavy bearings and a spindle designed for that harder work and mine has been in use since 1967. Before I bought my milling machine I used a small Bridgeport Bill Large had and made up parts ahead of actual need such as sear blanks and bridles.
Bill made it possible for me to make locks without using too many primitive and labor intensive methods. Small screws and tumblers I did on a 12x36 Atlas lathe and and then gota new 6x18 Atlas and made it into a screw maker as well as a macine to establish the thickness of the tumbler and semi finished support bearing shaft thru the bridle.I have 2 other lathes that I seldom use but they are there if needed.
Bob Roller