?? Best way to design the Z-axis movement ??

[old man emu]

Wouldn't that introduce more wobble than the traditional moving print bed, as you're moving and decelerating more mass?

I think that he electronics can cover that by setting the acceleration rate.

Don't forget that I'm looking at a 1200mm bed length. If I use a movable bed, then the machine will have a footprint that is over 2400mm (say 2500mm to allow for exterior parts of the frame). The moving gantry would have a footprint of, say, 1500mm for the same 1200mm bed size. We don't want to need an aircraft hangar to put this in. The movable gantry design would fit onto a dining table sized support.

Old Man Emu