There was a short discussion a while back about modifying stainless steel base rings. I have a Chinese A272 tube that I really like. But, whereas my MCM 50mm ring is just right, I tend to pop out of the A272 50mm ring. 45mm is too tight. I had all of my tools out since I am building a stainless steel exhaust system for my motorcycle, so, why not try? I was just hoping that while I was buffing the ring in my driveway, a curious neighbor wouldn’t stop by as they always do. I used the bandsaw to remove approximately 2mm. I squeezed it shut in the vice and put on a tack weld. I used my TIG welder to weld the gap shut. I profiled the weld and gave the ring a softer radius all around then polished it on my large buffer. I think it came out pretty good. 48mm seems just perfect! I was worried that the cast stainless steel ring would be full of bubbles and impurities. It wasn’t to bad for the most part.