Removing flux from a crankshaft after silver-soldering

After spending two hours machining the parts, I carefully cleaned, aligned, and silver-soldered them together.  Before final machining, I wanted to clean the remaining flux that didn't just pop off as the parts cooled.

After much research, I found that white vinegar might work, and since that's much less dangerous than diluted sulfuric acid I figured that I had nothing to lose.  As the before and after photos show, it worked really well.  Most of what I could reach with my fingers wiped right off, and the rest came off with a little brushing.