Originally Posted by
jon_norstog
The thinner the tube, the tougher it is. Smaller the tube, ditto. I was building BMX bikes, fillet brazing, back in the '90s. A lot of tifers did not understand fillet brazing and wanted none of it. About that time I met Jim Bedeaux, an Albuquerque gunsmith who had worked in the California aircraft plants after his WWII Marine Corps service in the Pacific. He was interested in the bikes, I showed him some frames, he asked why I didn't weld them. I said I didn't know you could weld chrome moly with OA. He said it's easy! And gave me a demonstration. Well it isn't all that easy but I stuck with it. All my BMX, slalom, 4X and extreme riding bikes are welded. One of them broke, I had THAT client, the one who weighs 160 pounds and snaps off a set of XTR cranks the same day he puts them on.
Another advantage of OA welding, and this is why I'm using it on cargo and expedition bikes, is that you can weld OR braze to modify or repair the frame. With bronze, once you've brazed a joint you are stuck with with it from then on.
My welds look better in person than they do under the harsh and unforgiving eye of digital photography. But that's not too important. I file them some to find any places that might have cooled too fast and gotten brittle. The most important thing, to me is to get thorough penetrATion, which basically wiped out that beautiful miter you did. The weld has to hold. Mine do.
Chris: no harm. no foul.
jn
