Hi Chaz.
A bit more speed would be nice and cnc is all about accuracy and repeatability I pressume? I will probably just change out the x y screws. The question is are 16mm screws rigid enough for this size machine and what would be a good thread? spacing. The acme screws I have are 16mmx4 what are the differences using a 16mm5 or 16mm 10? Would 20 mm rails be overkill. Also would it be possible to use the existing end bearings /supports and have the ends of the ballscrews machined to fit? Or go with new parts? Obviously the ballscrew bearing will have to be delivered with the screw. I won't be doing any production work but mainly wood cutting and some light work in ali and brass.
Cheers.
Andrew