I used the Steele plans to turn a 7 x 14 into a CNC lathe. I quit fooling with it because the leadscrew was not accurate. It doesn't use a ballscrew. It uses a very expensive screw with a plastic nut from McMaster-Carr. I would like accuracy no worse than 0.005". I don't see how I can cut usable threads if it's less accurate than that.
I would like to give it another shot, with a real ballscrew, but I don't know of a good source for such a screw at a reasonable price. I don't want junk, but it doesn't have to be from Tiffany's, either. Can someone recommend a good vendor? Thanks for any help you can offer.