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Discussion Starter · #1 ·
It's been a productive holiday. My front triangle is fully brazed, and I've finished (I think...) filing and sanding one of the joints.

I don't really know how much more metal I should remove so I'm asking you, the resident pros to chime in on this question; how big should a finished fillet be?

Also, there is the odd pitted bit here and there, that I'm guessing was due to not enough heat or not enough flux; these seem very isolated and small, please take a look.

Unfinished joints, and frame







The finished DT/HT joint pictures

DT/HT left side



DT/HT right side



DT/HT top



DT/HT bottom



Thanks for your help, everyone!
 

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Randomhead
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In general, pits are because of oxidation on the filler. You seem to have pits from that and also because you added material at too low of a temperature. However, you seem to be overheating. You can see this from the copper. Hard to know but it looks like the black scale is carbon from overheating.


Having said that, it looks like it should be safe to ride
 

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Discussion Starter · #3 ·
Thanks for the QC check, much appreciated.

The copper on the st/bb shell joint was done a while ago, when I had merely wetted that joint. I didn't know the whole process so I had brazed a few of the joints with the intention of doing the fillets later. The two TT joints are the only ones that were fillet brazed in one step. I'm still frying things from time to time, such as the sleeve where the TT and ST meet. It was very hard to get things hot enough to draw the brass into the joint.

The black scale you're seeing is the crappy Hobart flux I'm using. It doesn't matter how much I slap on or how careful I am, when I'm done the black mess is there. I can see it cleaning the joint while I'm working though, as it makes the metal completely clean (at least for a few seconds)

Drew
 

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Randomhead
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I considered the possibility that it was your flux, but it didn't look the same as the crappy flux I've been using, which makes a nice glassy black band around the joint. The gasflux stuff is worth every penny. The crappy stuff was making me look bad.
 
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