I have noticed when my Z is homing that I can visually see the router wobbling back and forth. So far it doesn’t seem to be affecting my carves although I haven’t done any 3d carving yet and I wonder if it would show up there on the carve. Could this be the ACME rod?
I’ve also noticed there is a ton of flex from left to right on the Z when I change a bit. Is that normal? Sometimes I feel like I’m gonna mess something up when the nut on the collet first comes loose. Am I bending the Z axis somewhere each time I do this?
Thanks for the input.
I recommend checking the V wheels on your z Axis.
On mine the hole for the eccentric nut was actual starting to get gouged and pulled out of shape.
i’ve had the same thing and for me it was indeed the acme rod. It seems a LOT of these are shipped bent. Not cool but it is what it is. You will notice a wavy pattern on 3D shapes with a lot of Z travel.
That is why I bought a linear rail Z stage from ebay. It’s also acme but at least it is perfectly straight!
Mine does the same thing. How did you solve?
I eventually got a new z axis that doesn’t wobble at all. 
