Don"t use hands when grinding

I have done that twice and still haven't learned. I would hold the electric motor in my left hand and then the cuting wheel would grab the copper, slip, and go right into my hand. Not once but twice. I remeber getting *****ed at the yard dripping blood walking in the door. WTF u doing they asked. I need to get paid, so I can go to the hospital. need it for gas money. LOL. They calmed down and helped unload the truck. I did it more than twice and still catch myself doing it here and there.