Arden,
Thanks, that is the good kind of Tiger info I was hoping for.
Based on what you said, the wire brush on my bench grinder may
have caused the problem of "adding iron".
At 03:50 PM 12/4/2001 -0800, you wrote:
>From our friends the beer brewers
>(http://www.howtobrew.com/appendices/appendixB-1.html):
>
>Appendix B - Brewing Metallurgy
>
>B.1 Passivating Stainless Steel
>A situation that often comes up is, "Hey, my stainless steel is rusting!
>Why? What can I do to fix it?"
>
>Stainless steel is stainless because of the protective chromium oxides on
>the surface. If those oxides are removed by scouring, or by reaction with
>bleach, then the iron in the steel is exposed and can be rusted. Stainless
>steel is also vulnerable to contamination by plain carbon steel, the kind
>found in tools, food cans, and steel wool. This non-stainless steel tends to
>rub off on the surface (due to iron-to-iron affinity), and readily rusts.
>Once rust has breached the chromium oxides, the iron in the stainless steel
>can also rust. Fixing this condition calls for re-passivation.
>
>Passivating stainless steel is normally accomplished in industry by dipping
>the part in a bath of nitric acid. Nitric acid dissolves any free iron or
>other contaminants from the surface, which cleans the metal, and it
>re-oxidizes the chromium; all in about 20 minutes. But you don't need a
>nitric acid bath to passivate. The key is to clean the stainless steel to
>bare metal. Once the metal is clean (and dry), the oxygen in the atmosphere
>will form the protective chromium oxides. The steel will be every bit as
>passivated as that which was dipped in acid. The only catch is that it takes
>longer-- about a week or two.
>
>To passivate stainless steel at home without using a nitric acid bath, you
>need to clean the surface of all dirt, oils and oxides. The best way to do
>this is to use an oxalic acid based cleanser like those mentioned above, and
>a non-metallic green scrubby pad. Don't use steel wool, or any metal pad,
>even stainless steel, because this will actually promote rust. Scour the
>surface thoroughly and then rinse and dry it with a towel. Leave it alone
>for a week or two and it will re-passivate itself. You should not have to do
>this procedure more than once, but it can be repeated as often as necessary
>
>
>----- Original Message -----
>From: "James Barrett" <jamesbrt@mindspring.com>
>To: <tigers@autox.team.net>
>Sent: Tuesday, December 04, 2001 3:51 PM
>Subject: SS trim Rust-NOT
>
>
>> Folks,
>> Received a bunch of mail about non Tiger related
>> subjects, and a few with questions about my Tiger. Is there
>> one Tiger Person who can answer my question about pickeling
>> or passivating my SS after I have buffed it?
>> James Barrett Tiger II 351C and others
>
James Barrett Tiger II 351C and others
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