Greg, no other specifics. I got boiling tank made myself from zync lined steel and when I started to blue my first barrels long time ago I tried to boil barrels in water any way. But with experience and when I began to reach good colors I figured out, that boiling in tank is not necessary. 1,5-2 liters of boiling water from tea kettle is more than enough.
From the other hand I use my tank for last step of barrel cleaning, when I put barrels in aprx. 1% KOH-water solution for several minutes to be sure barrels is 100% clean.
