By default, the AltMill comes with an 80mm spindle mount, which allows users to drop in any 80mm spindle without modification.
We have tested larger spindles (currently up to 4.5KW). You may require an adapter plate for larger spindles. Please see the drawings for the mount and Z-plate below, or reference the Onshape files here.
Here’s also a weight test on one of our AltMill prototypes to see how much load the machine can carry.