Sieg X1. Now with extra brurp brurp burrzzzzzup!

[Jonathan]

even just thrust bearings to even the manual machine. They make for a much smoother experience and kill most of the backlash dead.

Not that it really matters, but strictly speaking that's not quite true. Putting thrust bearings on the leadscrews reduces (ideally eliminates) screw end-float which is when the screw can move parallel to it's axis causing inaccurate positioning, even if there was zero backlash.

[russell]

Not that it really matters, but strictly speaking that's not quite true. Putting thrust bearings on the leadscrews reduces (ideally eliminates) screw end-float which is when the screw can move parallel to it's axis causing inaccurate positioning, even if there was zero backlash.

If you want to be pedantic end float on the leadscrew is backlash according to the Oxford Dictionary:

• 2 [mass noun] recoil arising between parts of a mechanism.
  
• degree of play between parts of a mechanism: typical gearbox backlash in these systems is 2°

Russell.