Great Design had lots of fun printing and assembling it.
Also does some good milling if you keep the feedrate and the cutting depth on the low side. Had some strong vibration in the z gantry when i milled som hardwood at 1000 mm/min and 2mm cutting depth. Increasing the spindle speed helped at that time, but since that i rather went with slower speeds and shallower cut.
I printed the mpcnc completely out of petg... less problems of parts cracking when you tension screws too hard.
Had my mpcnc up an running for a while and it was working great. But then my neighbour complained because of the noise of the 700 w katsu/makita router. I live in a apartment. So i swaped the noisy router for a 400w spindle and build a box for my mpcnc.
I square my mpcnc with 4 hardstops mounted to the rails. Before running a job or after doing a tool change i move all axis against the stops until both steppers on each axis skip a few steps... Then i zero the axis and run the job. I use estlcam so its easy to zero the axis in the cnc menue.
For those who are interested I use the TB6600 driver instead of the DRV8825... They can handle more amps, its easier to adjust amperage (no fiddeling with small potentiometers) dont get hot that easily, are a bit more inteligent (lower the current when not in use)... On the other side there are much bigger and wiring is not nearly as neat as with the drv8825...
Enjoy printing, assembling and milling :-)