Hi AndyUK / Kitwn

Thanks. I should have said 600mm x 600mm cutting area as I know that the cutting surface is less than the length of the rail.

The rails I have are 800mm and the ballscrew are 800mm between the bearing ends, so I estimate this should be enough to get the 600mm travel. I'm still working on the design, but the carriage width is 61mm, together 122mm, but I still need to allow some space for the grease/oil nipples, some safety space and space for the homing switch (if it is not flush with the plate). It's a steep learning curve! I'm working on a Fusion360 CAD model for the design at the moment.

What would you recommend for spacing of the two carriages on the rail? It seems most designs place them with no space next to each other (potentially giving more travel on the rail), but I've been thinking that adding space (perhaps the width of one carriage) will help distribute the load better on the rails (but given the strength of the rails/carriages, I'm not sure wether it will be such a big advantage).