I'm about to build a CNC machine with 3 axis, got all mechanical accept end switches and spindle (for starting it will be a Dremel but if I get all to work and find it possible to make some ideas happen, then it will be upgraded with proper spindle).
Using Uno and CNC shield (got a mega as well if my idea is to big for Uno).
And a old laptop running CNC Linux for generating and send g-code.
Have only experience for building, soldering electronic so new area for me.
My idea was to be able to ad a jog wheel, a display, led-diods and a few buttons/switches to be able to set all axis manually.
One switch for choosing manual or from computer.
Switch (got 6-way switch so it could be one for each X+, X-, Y+, Y-, Z+ & Z-) to choose axis and led showing what axis is active.
Jog wheel is connected to display so you see how many steps you choose.
And a button to press for sending your chosen settings one axis at time.
Would that be possible to do?
On Uno or Mega (if understand correctly then I can't put CNC shield directly onto Mega as pins different)?
An even more difficult idea is to combine CNC, 3d printer and laser engraver but my guess is that it would take 3 Uno (one for each task) and a lot of work.. and I might never use all 3 in same product.