for A axis rotary stepped motor can attach to Z axis?

CAD & CAM Tool Chain LaserWeb/CNCWeb
,
1

for A axis rotary stepped motor can attach to Z axis? my cnc shield only z is free.

2

Yes you can, just you need to setup the steps accoordinly

3

+Ariel Yahni​
means need to adjust grbl setup, right?

4

Yes.