Again on the phosphoric acid.
Novahokie had generously offered to share some of his gallon, but couldn't make it to the last pick-up, so we missed out on that. Maybe he'll be still up for it this this buy, maybe not.
If anyone is interested I'm willing to coordinate a share/split of a gallon or 2 from Duda Diesel. A pint of 85% goes a long, long way. You can also use it to locally passivate stainless steel in a pinch, although nitric acid (or citric acid) is preferred, both after a thorough degreasing and washing/rinsing step.
From Duda Diesel it runs about $11 a quart, including shipping, if purchased by the gallon. A bit less when ordering multiple gallons.
The bigger challenge is to find suitable bottles in pint or quart sizes. You don't want this stuff to leak over your brewing equipment, garage floor, or way worse.