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Stainless Steel Corrosion Question

I added some diluted muriatic acid to my sink because a stupid plumber dumped tile cement/grout (CaCO3) and I wanted to unblock the clog in the PVC pipe (2 inch dia) below. The steel rim that fits the sink drain and cups it into the PVC pipe below has a stainless steel surface and it is all black and murky brown. Is there any compound I can use to polish off (remove) the FeCl2 (ugly murky black-brown deterioration of the steel by the acid) precipitate and bring the shiny steely gloss back to the stainless steel rim?

Thanks,

Dipak V. Desai
- Houston, Texas, US
2003

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The part you are describing is typically chrome-plated brass. Iron chlorides are water soluble, so you have something else. It may be time to have a good plumber replace the sink or at least the drain.

To all D-I-Yers: Commercial drain opener products, both acidic and caustic types, contain inhibitors to protect metal surfaces.

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.
2003