[Shop-talk] alternative fluids for parts washers

[David Scheidt]

On Fri, Apr 16, 2010 at 5:07 PM, Randall <tr3driver at ca.rr.com> wrote:

> > No personal experience, but I have been told you can wreck aluminum
> > parts with Simple Green.
>
> I believe the concern is real, but only under fairly extreme circumstances.
> The problem arises with fairly thin riveted sheet (like aircraft skin),
> where the SG can soak into tiny crevices between sheets or around rivets
> and
> get trapped.  Over a long enough period of time (and likely thermal
> cycling,
> etc.) it can corrode the aluminum enough to weaken it.  ISTR there was
> actually an aircraft skin failure traced to this, and so it's now forbidden
> to use any strongly basic degreaser (like SG) on aircraft.
> \


It's also probably dependent on alloy.  High strength aluminum alloys tend
to be more prone to crevice corrosion than the sorts that are used for
castings.  but htere are any number of less nasty degreasers available these
days (usually with better pricing, too.).


-- 
David Scheidt
dmscheidt at gmail.com