Thread: Small Black Problem.

Lewis, I had a similar problem (but not with stainless) and I did some research which led me to putting 250ml vinegar per litre in the pot, and sufficient quantity to cover the blacked area.

Boil for 15 minutes, and then leave it stand overnight. Quite a lot of the carbon was loosened after this and quite a lot more came off with subsequent scouring (with very fine steel wool - from the shed of course).

From memory I repeated this another two times (certainly one at least) over a few days.

Nothing else I tried worked, and this eventually got there.

HTH
Brett

EDIT: I used floor cleaning vinegar (not that it's stronger, just cheaper)

Hi
After welding stainless steel we treat the welds with Avister pasivating paste. You can probably buy it from welding supply places. It takes out the heat marks from welding with a little work with steel wool or a wire brush.It's mainly phosphoric acid and is preety bad stuff. You need to were industrial strength rubber gloves, eye protection ect. Don't breathe the fumes. We also use nitric acid.

Merry Xmas
Kev

A strong caustic soda solution works well and you can clean the drains after when you pour it away Just don't use ali pans
Pete

I vote hot caustic solution too!

Bought some of this stuff from the garden expo in Nambour a couple of years ago.

Works like a charm, very easy to do and for once, it works. No affiliation just a user. Mainly use it to clean the glass shower screens - only need to do it a few times a year.

Safe and Clean – 750g Household Tub | Amaze Products