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

[old man emu]

. Would stability be improved by having the two x rods on the same horizontal plane, instead of the same vertical plane? Are you thinking of using extrusion instead of rods?

I have a design for a gantry machine that uses two rods for the X-axis track. With linear bearings that will make that assembly very rigid.

Since this machine is going to be semi-industrial, I am going to use bright bar instead of the nice shiny chromed bar normally used on Prusas. Have you ever priced that shiny bar? I'd need to sell my first-born son to buy the nearly 6 metres I'd need for the X and Y runners. A bit of lubrication will let the bearings slide.

OME