What causes this staining

[GDW]

What might cause the rust coloured stains?
Wondering if that’s cosmetic or the sign of a problem.

 

[sasqman]

My thoughts are that the stainless cap has a higher iron content (cheaper stainless) than it should hence the rust colors dripping. Take the cap off and go to a sheet metal shop and get a new one made in 304 SS.

 

[ericl]

Could be electrolysis from lack of anode(s) - picture needs to be of better quality.

FYI Stainless = stains less esp in S/W.

 

[Rayvon]

The stainless cap is poor quality and when the cap was welded they didn't "pacify" the welds,which means that the chrome in the stainless wasn't brought back up to the surface.Pull it off and have it done right ,only permanent solution.Or you might be able to find a plastic cap from the original manufacturer.Campion?

 

[ReelSlim]

Another thing it can be caused by is how it was buffed. I have seen guys build a great stainless steel project and polish it will a wire wheel. It will impregnate the SS with rusty old wire. A proper flapper style buffer works great.

 

[SteelyDan]

Rayvon is correct. Its called "pickleing". It can still be pickled