Upgrading a MAKKO M850 cnc machine ?

[the great waldo]

Whilst I cant prove it without delving into some specs of the screws however Acme is not exactly accurate. We used them for 3d printers, they are OK to move things from rotary to linear but its nowhere nearly as good as a proper ballscrew.

Sure, there are better nuts available (delrin etc) but it simply cant be as good, surely? I would have guessed (and its a guess) that the tolerance difference must be large between acme and ballscrew.

Hi Chaz and all

would it make any sense to use a 20 mm ball screw or would 16 mm be stable enough also what pitch on the thread would be the best for a woodworking machine. I won't be using this for a producton machine as such. I've got a 2.2kw air cooled chinese spindle and Hitachi inverter which I also need to mount sometime. The kress motor runs ok for small parts but only goes up to 8mm cutters , hence the 2.2kw spindle. The machine frame itself seems pretty rigid. I'm in Austria so if anyone has links to good ball screw suppliers in Europe please let me know. Any information gladly accepted.
Cheers

Andrew