Just to muddy the waters.
At the LaCrosse event there were some of the best smiths int he US attending. We asked about the white powder and were told it was "salt". Several of us tasted the powder to check for borax..anyone who welds with the stuff know the taste...it was borax.
I asked specifically what it was via the translator and it took 30 seconds of talking to again return with "Salt". When pushed and told it was borax there was a shrugging and again the word "salt" was mentioned.."it is salt".
This could have been an error in translation or understanding or many other possibilities, but in the end..no matter the terms...the flux was borax with a dip into the straw ash following. I believe I still have a scar on my face to prove the fact...you see I did not see the white powder the first time and was sitting just to the left of the powerhammer...when I weld with just straw ash I get no violent ejections of material..so I was expecting none...Enomoto even warned me just prior to the blow, but I KNEW BETTER you see....I was better prepared the second time.
I am sure Bill Fiorini could have offered supporting evidence to what Bowen is saying, but all we have of Bill's knowledge our own memories. Though he and I spoke of flux more that once before his passing.
I know I work differently depending upon who is watching, what they have come to see and what flavor I wish to leave in their mind when they go.
Ric