[Andrew Schuetze]

Originally Posted by Éowyn

That looks fairly similar to a globe motor mount I made last year. Those little holes were a real pain in the drain to line up.

Those little holes are actually tapped for a machine screw and washer. The intent is that they will capture the flanged ball bearing. I uploaded the wrong file. The final version has a 0.500 inch fillet to round off the corners on the bottom.