[EricH]

Trust me, it's easier to do it right during build season if you practice doing it right during the preseason. I'd start with Don's suggestion--but on your first one, try to hold a 0.010" tolerance. Then when you can hit .010 almost every time, 0.005". Repeat going down to 0.001".

If you can hold a 0.001" tolerance on a manual machine repeatably, you'll be in good shape. It's not exactly easy to do without practice.

For a bonus, you could try making a C-clamp. You'll need both a lathe and a mill for this; the tricky part is the screw/C interface. It can take a while to do it right; get help from whoever's advising you.