So I decided to motorize my barley crusher, and I've decided to direct-drive it, using a gearmotor. My question relates to the way one connects the shaft of the mill to the shaft of the motor. I see that most people use "lovejoy" connectors with a spider. My question: what is preventing the shafts from just spinning around inside the lovejoy connectors? I already ordered and received the connectors from Grainger - I did not order the ones with a keyway, but the ones I got seem to have one anyway, but no screw to put in there, nor is it clear to me what size screw I would use? Is a keyway necessary anyway?
Any advice appreciated!