Hey Dan,
yes, you need to load the correct configuration:
This applies to firmware 1.2.1 and later.
Should you be on firmware 1.0.9 or earlier, after installing Z-20 assembly, you need to set these values of Motor 3 on its MOTOR page manually instead:
- “travel-per-rev” to “10”
- “min-soft-limit” to “-160”, and
- “max-velocity” to “7”
This is what the “Pick your Z Slider Type” choice sets (as shown in the image) above when choosing “Z-20 Heavy Duty”. The Z-20 assembly will work correctly if you set it manually this way.
Note that additionally when using a heavier milling motor, you can adjust (increase) the ‘drive-current’ and ‘idle-current’ settings the “Motor → Power" section of motor 3 on the MOTORs page.
Should also stall homing on Z axis not work correctly, you may also adjust stall homing settings (see here for details).
Welcome to the forum!