Anet A8 threaded rod bracket with slots for M4 or #10 pan/round head screws

thingiverse

I'm designing a hold-down clamp for printers, similar to the one on Thingiverse (https://www.thingiverse.com/thing:2390954), but this version uses slots for M4 or #10 round-head screws instead of countersunk holes for flat-head screws. The reason I'm using slots is because after mounting your printer to a surface, you should check its Y-axis alignment with the X-axis by printing a large square and verifying that all four corners have right angles. When I did this, I noticed two corners were about 89 degrees and the other two were around 91 degrees, so I adjusted my printer's front by pushing it about 3mm to the left to make the Y-axis perfectly perpendicular to the X-axis.