Its been suggested that it may not be the best idea to use the tool pictured on the bottom, as there is a chance that the wire that makes up the brush could break off and plug up holes at the mouthpiece. Certainly seems plausible. The tool on the top worked nicely.
Cleaning the plunger. Bill brought this device. I'm sure most folks don't have access to one of these. I'd be interested in hearing other folks' routine / technique in cleaning the plunger. From a safety standpoint cleaning the plunger is where exposure to potential dangerous oxide seems to be the greatest.
Before re-seating the plunger in the well, we placed it in the pot to bring it up to temperature for several minutes.
Fluxing the metal. Takes just a couple small flakes to do the job.