Barkeepers Friend

[emnpaul]

I've never needed to passivate a weld, so can't comment on that.
However, it's made from the same stuff (Oxalic acid - and some Citric Acid) as Bar Keepers Friend and picture-proof of it cleaning minor surface rust/pitting from stainless can be found on my blog here - if you really need it - I can take a picture of the same keg several brews later showing that it's still passivated. I also easily cleaned the deeper/older/more pitted years-old-rust from the exterior of the kegs (where they had been scrached, bashed and dented) with it, but did not bother taking photos.

It's the acids that perform the cleaning/passivating, not something magic in Bar Keepers Friend - which is why (commercial type breweries) rinse stainless equipment with an acid wash (5 Star make 6 acid wash/rince products) - especially after cleaning with caustic-type-products, and home brewers can use something like Saniclean (Phosphoric acid).

Thanks for your reply Wolfy.

I don't think extra photo's are necessary as I'm happy to take your word for it. I priced some pickling paste from a welding supplies place and it was $50 for a 1 kilo tub. I was hoping to get out of it a bit cheaper and it seems it might be possible.

In a past life the stainless blokes at work used to use pickling paste on welds that I think was a mix of oxalic and hydroflouric acid. They could scrub it with a scouring pad (I think) and wash off in about 10 minutes, so hopefully if I'm patient I can get away with the bar keepers friend or similar.

 

[Newts]

On this one, does anyone know what's best. The powdered stuff or the liquid? Got a little rust forming in the bottom of my keggle and seems this is the easiest way to fix her up. And If it happens again I'll have some handy.

 

[lael]

Not sure. I got powdered and put it on a sponge and add a touch of water to make a paste...
Found it at House in Parramatta Westfield.

 

[razz]

I just got an email from the Aussie distributor to say that BKF is now available in Coles stores.

 

[enoch]

I just got an email from the Aussie distributor to say that BKF is now available in Coles stores.

Yep saw it on the weekend. $7-8 for 340(?)g.