Framebuilders - Welding canti boss?

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Evoracer
11-26-07, 01:38 PM
I know the preferred method is brazing. But, is there any inherent problems with mig welding cantilever bosses on a set of forks? A have experience with the mig and blow through associated with thin metals.
Thanks
PDXJeff
11-26-07, 02:28 PM
With proper alignment of the bosses, it could work. A TIG weld would be much more preferred. (cleaner, smaller)
I'd buy an extra set of bosses and do a test run but I think it would work. I'd' trigger' weld it, a fancy term for a bunch of tacks. it probably wouldn't take much
I have seen some frames where the bosses were clearly jigged off the tubes a few mm, and a blob was shot on either side at the bosses at the 3 and 9 o'clock positions. The advantage to this approach is that you can squirt with a MIG, and make two strong gussets, rather than trying to make a hole in one by running a perfect chain of dimes around each boss. The latter is the ideal situation for the heat control from a TIG.