Building my first CNC router. Going through McMaster I think I have found the acme screw I need, as well as lead screw, and end supports. Reading through the forums I keep running into two terms, and I really have to apologize for my total ignorance here, hack saw and file.

If I understand correctly, I have to hacksaw the lead screw to length, then i Have to file it flat.

First off, how do I select a hack saw and file for this procedure? Secondly, my attempts in past of cutting steel with hacksaw have all resulted in weapon bits rather than machine tools. So I guess my question is, how do I do this?