Recent content by impact.walter

I’ve also experienced this. I’m trying to reconcile this statement with a pressure-ferment being capable of purging a keg of sanitiser which I haven’t done, but am impressed by.

I drill a hole in the cap for a grommet and for a standard airlock. I keep several drilled caps to replace the caps on new bottles for each new ferment. Sanitised off course. :)

Same here. But, you might keep a finger under the bottom cap. No need to ask why I now always do this…😁

“Self-passivation” on SS can only occur on very smooth surfaces, and is predicated on a fine surface finish. Pits and fine marring in SS cannot self-passivate no matter the treatment, even under ambient gaseous conditions, if in the presence of an electrolyte (in this case moisture, salts, acid...

Nitric is nasty though.

I see others have mentioned citric acid already. I think the suggestion is good. Passivating 304/316 stainless with citric acid is now quite common in several industries, including CIP in dairy factories. I haven’t personally used citric, as my applications have been marine and chemical industry...

Pitting (especially multiple small) is awkward. I’m not approaching this from a sanitary perspective as there are advisers here who are more knowledgeable than I in that department. The brown colour is likely ferris oxide. I would personally work on the premise that ‘iron’ oxide isn’t bad for...

As to sanding, I assess that as pit corrosion, for which sanding isn’t really appropriate as sanding is a surface process. For marine stainless (316) patient very fine sanding is applicable to remove shallow surface marring which presents as an unsightly surface ‘rust’, ie micro crevice...

Thank you for your encouragement. This is the first site I’ve found with practical & knowledgeable posters, found ‘accidentally’ as an informative link from elsewhere. And I’m happy to be here.

Beer but mostly Cider. Low tech thus far. Novice. 23L plastic fermenter. 5L glass demijohns. 30L ”AllRounder” (on order). Learning yeast, fermentation, carbonation.