I tried to use the band saw last night and the blade is basically trashed.
Additionally, the crank wheel popped off in my hand, and it looks like the little piece that fits into the groove on the handle (hard to describe, but you can see it in the third pick) had come off. Without that, the wheel just spins without doing anything.
I put a lockout tag over the switch, but only the front half fits over it.
The flat thing you referenced is a shaft key. It sits in that recess on the shaft and a set screw on the hand wheel keeps the hand wheel in place over it.
ETA: The bandsaw is up again. Blade just seems to have needed reinstalled. Handwheel is reinstalled as well.
Thank you! 
Well, this time I’m pretty sure the blade broke. I heard and felt a crack, and adjusted the tension which did nothing.
This is why we can’t have nice things! 
