I see him using a mill and lathe multiple times. He even uses a CNC at least once in part 5. All the machinery he uses would have been something available to a machinist in the 50s. He's not using a plasma cutter but he's using relatively modern tools that an ancient greek bronzesmith couldn't even dream of.
I think he just uses the Mill and the CNC to speed things up, but some parts (like the gears) he does completeley by hand with a file even though he could do it way faster and more precise on a mill.
