An old timer in Mobile told me my weld prep was too clean
Back when I was a helper, maybe 15 years ago, I was grinding a bevel on a 6-inch pipe for a boiler feed line. I had it polished like a mirror. This old fitter, Frank, walked by and said, 'Kid, you're leaving it too slick, the bead won't have anything to bite into.' I was confused because I thought clean was best. He showed me how to just rough it up with the grinder, leaving tiny grooves. I tried it his way on the next joint, and the penetration was way better. Anyone else get a piece of advice that went against what you thought you knew?