[Prusa Core 1 - Update 2] So it turns out you can break screws

I made some significant progress on assembling my 3D printer. I got the CoreXY frame mounted, the extruder assembled and plugged in. Just need to put on the rest of the frame and the panels. But while tightening one of the screws that connects the frame and the CoreXY plate together, the screw broke. Like, the head of the screw came clean off. I didn't think I could even exert enough force to…