What do you look for under microscope? I’ve got a rather powerful hand held magnifying glass that I look at my needle from time to time, but if it’s clean, and riding in the groove at the correct angle, I’m not sure what I’d be looking for? Do you save photos from previous inspections to compare to? I would think that even under a microscope it would take a thousand hours for you to actually see wear? Or am I wrong on that?