The imperfection is on the right vertical wall. I did change the orientation for the second block to see if it would change anything (Printed the long end facing up instead of flat) and it didn't make much of a difference aside from that one little perfect area about 3/4 way up. Not to say that may not have happened on the other print at some point also though.

I'll check all set screws but given the fact it only happens on one face makes me feel it's not a loose set screw as it wouldn't be so consistent to only one face. I also ensured the slide rods were clean.


Dave