Skip to main content
Gerry | Vanagon
Checking account...
← vanagon.com home · Continue the discussion in the forum
Subject:Re: Exhaust Pipe Rust Prevention
From:Bostig Eng.
Date:Tue, 22 Nov 2005 18:04:28 -0500

The magnet test is good, but not because of iron content. All stainless (in
fact all steels) are iron alloys, the magnetic properties are a result of
the structure the metal. You can take a piece of 304(usually not
ferromagnetic) and beat the crap out of it with a hammer and it'll become
ferromagnetic because you've changed the structure(I've tried this HIGHLY
scientific test).

  The corrosion resistance is related to Chromium and nickel content (as
well as others, Ti in the case of 321).  There isn't really any such thing
as "crap" stainless, but only stainless that is "crap" in certain uses...
ideally we'd all have 347 or 321 stainless exhausts.

At 01:22 PM 11/22/2005, John Reynolds wrote:
>A quick check for "crap" stainless is put a magnet on it.  400 series
>stainless has iron in it, therefore, it is not as corriosn resistant as
>300 series and hence the magnetic properties.

Jim

________________________________________
Bostig Engineering
http://www.bostig.com/products/zetec/
978.772.3274
----------------------------------------------------------------------