Guys, I am just sorting out in my mind (and on the back of loads of envelopes) a few details for my mill build. There is nothing unusual in the design, an X-Y table and a Z.

On the Y I have the screw stationary with a moving nut, the X has a moving screw with a fixed nut.

The Z could do either. My question is which is the preferable method, fixed screw or moving screw??

:confused:Advantages and disadvantages of both options in words of less than 2 syllables PLEASE!!