Subject: Re: Magnesium corrosion - removal

From: [email-masked] (Yogi Shan)
Date: 10 Feb 1995 21:05:58 GMT

[email-masked]

**>  I would recomend against sand-blasting 
**>  or anything that might raise a lot of 
**>  sparks.  Remember that Magnesium is 
**>  flammable and you can't put it out.

It's always good to err on the side of caution,
but this is a bit much.  Magnesium will not
catch fire that easily, except in finely divided
(powder) form.  In any substantial thickness,
forget it.  A Magnesium alloy VW crank case
would *absolutely positively never* catch fire
from sparks.

**>  Magnesium can be etched with acid, but
**>  I don't think it will help on the 
**>  corrosion.  Try Nitric acid in a weak 
**>  solution on a spot and observe carefully.
**>  Keep well-ventilated!

Well-ventilated from what? The hydrogen gas
produced?

A dilute hydrochloric acid solution (*SLOWLY*
add 1 part hardware store muriatic acid to
5 parts cold water, then mix) would be
just as good and cheaper and easier to get,
and will clean up the corrosion quite nicely.

Use standard  safety precautions for working
with acids and other corrosives, and use a
small test spot first, as this poster mentions.

Yogi