Gentlemen
I agree 100% and I see my questioned has been answered, but just to through a spanner in the works. For my own curiosity.
One, backlash easily can be adjusted for in Mach! Yes ball screws can be more accurate but a lead screw that cuts threads is not to bad as well you have to admit. The other point of friction Why don't we simply use a larger motor with a reduction to the screw, solve that problem.
Please don't take me wrong, I'm not trying to be difficult, its some answers I would like to know. Its OK doing something because you have been told that's the right way, but can the wrong become the right way?
Cheers
Katoh