Yep, we''ve all done it many of us more than once,,,on my .049 engines I can pinch the spinner with my thumb and finger to stop the engine...once bench testing a .40FP and reaching (for what I dont remember) when the prop tip went through my finger/ nail long ways...it looked like something that would never heal properly, but the human body is pretty amazing and it looks like it never happened now, but that years ago....Rog