BB Follow on braze

[macky]

Hi - A few years ago, I took the UBI course, and after completing the BB shell braze the instructor pointed out the lack of silver in certain areas. It was recommended that I add silver when brazing in the CS, which I did, and all that worked out well. My frame has shown no signs of stress over the years since.

Belatedly, I am working on frame #2 , and after completing the BB (and front triangle) it appears I repeated that mistake. In a normal world I would have gotten after that and used the same process I learned in the course when brazing in the CS. Complication: COVID, so I haven't been in the shop for awhile. I'd like to get after it again but the frame has been sitting for months. 2 questions:

1. Is it okay to use the same process I used in the course or is there a problem with the amount of time between the first and second heating? i.e. if I had gotten after it the next day (as I did in the course), does that make it OK, while waiting a few months makes it not OK?

2. Not related to the time issue in #1 , I have always been curious about reheating a joint and the process around cleaning and fluxing. Realzing I am not taking the joint completely apart, cleaning and fluxing all around, is there a process one follows when reheating a joint in regards to cleaning and flux? Been wondering about this for awhile and have never seen it discussed, so if this has been hit elsewhere a link is appreciated.

Thanks much.

Mike Cormack
Vancouver, BC

[e-RICHIE]

I’d never reheat a joint, or suggest it as a fix, in order to improve its integrity. If you want / need to dress up an edge because of how it looks, simply use the smallest tip and lightest flame possible and quickly reflow some of the filler material.

[macky]

Thanks Richard. Good to know.

[progetto]

And don't forget the importance of cleanliness and plenty of flux.

[macky]

And don't forget the importance of cleanliness and plenty of flux.

That was well emphasized at UBI for sure. Thanks for that.