At work I was discussing this matter with a customer.

I'm interesting in knowing conventions for labeling your axes. While this
has virtually no deep meaning in manual machining, it is exceptionally
important in CNC machining.

I am under the assumption that the "Z" axis is always coaxial with the
spindle. This means that vertical CNC mills have the Z axis going "up and
down", horizontal CNC mills have the Z axis going "forwards and backwards",
horizontal CNC lathes have the Z axis going "left and right" while vertical
lathes have the Z axis going "up and down".

Are there any standards which dictate axes for certain types of machines?
I.e. ISO, DIN, ASME, AISI, CSA, MIL Spec, etc.

We'll leave out extra axes like W for a bridge mill and that kind of
thing...

Thoughts?

Regards,

Robin