Stainless steel won't come clean? (black residue)

[Moarhops]

Hi all

I've spent the last two days soaking and scrubbing a brand new SS Brewtech 1 bbl unitank and I can't seem to remove this black residue on the interior. It's invisible to look at (it looks lovely) but if you scrub the inside with a white tissue it comes out with black on it.

I've soaked the tank in hot (60C) TSP solution and scrubbed it thoroughly twice. I've also repeatedly scrubbed a trial area many times and the black always seems to be there.

I'm assuming that this is some kind of dust left over from polishing but if that's the case it's surprising that it doesn't seem to shift. Anyone experienced something similar? Is it possible that there is a defect with the metal itself?

Thanks

 

[day_trippr]

Get some powder Bar Keepers Friend, make up a thick slurry, and go to town on that kettle with a stiff sponge (not a scrubby - that'd be overkill in this case) then rinse well and wipe any haze off with a damp towel (or do a quick/light wash with a bit of dishwashing liquid).

If you still get any transfer off the kettle something is definitely wrong...

Cheers!

 

[bigdawg86]

Forgive my question, but any metal will rub color onto a cloth if you scrub enough no? You can polish a silver spoon with a mirror finish and still get black residue on the towel...

 

[day_trippr]

I don't think that always works.
I always towel-dry my SS kettles at the end of a brew day and I can testify there is never any "color" on the towels...

Cheers!

 

[Moarhops]

Get some powder Bar Keepers Friend, make up a thick slurry, and go to town on that kettle with a stiff sponge (not a scrubby - that'd be overkill in this case) then rinse well and wipe any haze off with a damp towel (or do a quick/light wash with a bit of dishwashing liquid).

If you still get any transfer off the kettle something is definitely wrong...

Cheers!

Thanks for the suggestion! I should have mentioned that I turned to the trusty BKF for a patch to test it out. Same problem...

Forgive my question, but any metal will rub color onto a cloth if you scrub enough no? You can polish a silver spoon with a mirror finish and still get black residue on the towel...

I wouldn't have thought so. The paper towel isn't as hard as the metal so cannot abrade it. I did the same test on my HLT and BK and got clean results despite vigorous scrubbing.

 

[flars]

I use a paste of Barkeepers Friend on my stainless steel with a pad of paper toweling. Wipe it down and then rinse well with hot water. Small pieces I will add a little heat to speed up the drying to passivate the surface. Air drying just takes a little more time. Check out the web sites for quality stainless steel cookware for procedures.

 

[cotsi95]

Thanks for the suggestion! I should have mentioned that I turned to the trusty BKF for a patch to test it out. Same problem...



I wouldn't have thought so. The paper towel isn't as hard as the metal so cannot abrade it. I did the same test on my HLT and BK and got clean results despite vigorous scrubbing.

Don’t use bar keepers friend on the etchings it will take them off.

 

[gimmeaberrr]

Plain white vinegar is what we used to use in restaurants to polish our SS and it works like a charm. Maybe give that a shot. Plus being an acid it should help remove any scale (if this is scale??)

 

[613Brew]

Had the same problem with my SS BrewBucket. Thought I got all the residue, so I brewed a batch. Noticed the same black residue in the crease where the conical part starts while cleaning after the batch was done. It did not affect the taste (phew!), so I gave it a good rub again with TSP and re-did the whole passivation with StarSan. That took care of it... Good Luck...