How do I change units from inch to mm?

Any entry box that has “in” in it (to mark it as “inches”) can be changed to metric by entering “mm” after the new value.

For instance, if you see a value of “.125in”, you can enter “3mm” or “3 mm” to change the value and the units.

The units will be remembered for next time so that you can just type “5” and MeshCAM will interpret that to be “5 mm”.