How Not to Sharpen Mower Blades

Ok, it'd been a while since I'd sharpened the blades on the mower. It was high time to correct the months of abuse. I pulled both blades off of my 36" mower and got out the pneumatic grinder. I started down the first blade and about 10 seconds in I hear a "POP". I think, huh, that's not good then look down to see blood running down my leg. I realize that a part of the abrasive disc exploded and the ricocheted off of my leg. I realized that albeit painful, it was only my leg, it was minor and I was going to live. I was thankful it wasn't an eye or finger or a 'nad (now I'm wondering why they're ordered that way). Anywho, my sexy nurse slapped on a few bandaids and, my cool tool now wrecked, I finished with a good ole' hand file. Good times.

Crappy day 1 pic. Day 2+ looks a lot worse with brusing.