Well, this happened last weekend....
Running an Evan's Pole Star. I thought the safest thing would be to start and tune it on one of our fields run-up stands which has twoxfours to hold the wing, since the tail on the polestar doesn't have a stab and could slip out of a helper's hands. I unfortunately (and without forethought!) placed the xmtr leaning against the left wing panel. After tuning up my 9 year old O.S. 70 to it's best attempt at full power, I reached around the APC 12x6 for the xmtr and forgot that the last half inch or so of that gray APC is invisible at even a mild idle (~3000rpm).
Result: 9 lacerations starting at the base of right thumb and traveling down the pad to almost the wrist, one ER visit with wife and two kids along, 23 stitches then and 4 more next day..... and ruined my best Jimmy Buffet T-Shirt.... It hurts to even type, since I damaged two tendons and won't recover use of the thumb for a few months.
Before and after stitches pix attached. Don't look if you're not a fan of bloody horror movies!
Be careful out there. I'm setting here looking out the window at a cold but nice flying day and the guys from the club are out at the field flying....