CNC router for wood processing

[Andrewg]

I'm no expert, but seems like you have grasped the basics of the challenge and are grappling with the details.

Two minor points:
- Wood machines need speed, and so more normally use 1610 ballscrews. You can do the maths, but might want to gear up between stepper and ballscrew.
- As linear rails carry two spaced carriages wider than your ballscrew, typically ballscrews can be shorter than their rails.

A major contributor here always stresses ' buy nothing till you have finalized your design' but guess you have those parts already.

As to rail leveling, you are quite correct to focus on this as a key step to building an accurate machine. You will find plenty on this forum about epoxy leveling. If done right, it addresses both leveling the surface for the rails and getting them coplanar. Your adjustable screw approach is an alternative for leveling each rail, but seems a lot of work verses simply shimming the rail.

Good luck with your planning