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Stainless knives rusting

2006

Lately we have been having trouble with knives rusting while sitting in a sterlizer at a meatworks.
For some reason the knives are coming out with rust spots all over them. Different brands have been tested to insure it's not a bad batch from one company, some have been sharpened then placed in the sterlizers while others are new, straight out of the packet. Water temp is greater than 82deg and water pH is between 6.3 - 6.4.
Does anybody have any ideas on what may be causing this?

Fil Farina
- Bordertown SA Australia

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Perhaps some form of chlorine. Make sure that there's no bleach (hypochlorite) residue, then try using distilled or demineralized water in the sterilizer.

If this works, get your present water analyzed. Activated carbon filtration can remove chlorine, but reverse osmosis (RO) may be needed for chloride removal.

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.
2006

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The possible explanation - lack of oxygen, required for passivation, during sterilization. The suggestion is: submerge knifes in the solution consisting of 1% of baking soda [in bulk on eBay or Amazon [affil links] plus 1% of hydrogen peroxide. Then without rinsing put knifes into sterilizator.

Anna Berkovich
Russamer Lab

Pittsburgh, Pennsylvania

2006