I was going to post this in guides and resources, but it looks like I don’t have permission for that. Maybe someone can move it later.
At any rate, a frequent question appearing on the forum involves a drifting Z axis - either up or down. There are a few common reasons for this, and I thought I would consolidate the various troubleshooting steps all in one place.
Simple steps first:
- check and see that the Z zero position in your model is the same as the Z you are dialing in with the probe.
- ensure that you are not bottoming out on the end of Z axis travel when you are attempting your deepest cuts.
After that, typically there are a few potential sources of Z axis irregularities:
- check that the coupler between the Z motor and lead screw is tight
- check that the bit is tight in the collet (always tighten with the two supplied wrenches, never with the red bit lock button)
- check that the router is tight in its mount
- ensure that you are not plunging into the work so quickly that the Z motor is losing steps
From my experience, an up-cut bit might pull itself into the work and a down cut bit might work in the opposite direction (and I have indeed seen this happen in my own work with an improperly tightened up cut bit).
I hope that is helpful to all and happy carving!