3 axis surface grinder linuxcnc

Hi guys , next project a Elb surface grinder . I want to retrofit the machine because this osai control is conplicated to use. My plan is x axis Larkin step to linear , y axis same , z axis stepper with realtime processing bord ( this bord we think it dont work on servo and for this we want to you a gap conpensation board ) . Then we want to use a 7i76 because the compensation bord has only puls/dir. The axis on z is trapezioidal 1mm . My problem is that i need to axis is auto , like a macro and z axis working in manual from handwheel. Olso i need to develop a custom macro interface to make the program from mdi. But in mdi z handwheel dont work. I have attach a video of a favretto grinder that works like i want

What servo motors and drives are on that machine?
Show picture or video of the cabinet showing the drives.

I would guess AC servos. This should be no problem to convert to Linuxcnc.

They are ac servo with velocity command +-10v . My problem is the logic of the NC . The xy axis your in auto but z axis works in manual . That mens when i start a program my z axis still move from handwheel. I have done 12-14 machines only in milling with mesa this is diffrent configuration

If you use the 2.8 branch then it is trivial to hook up a handwheel as an external offset to the Z axis. Then both LinuxCNC and the handwheel can move the axis. (which means that you can trivially add a retract and return button, for example)

I will need to do some reading. The external offset must have some hal pins somehow.

linuxcnc.org/docs/devel/html/motion/external-offsets.html