On Sun, 01 Feb 2004 20:17:56 GMT,
(O-ring Seals) wrote:

On Wed, 28 Jan 2004 01:32:55 GMT, Orval Fairbairn
wrote:

In article ,
Ed Wischmeyer wrote:

Folks, the question is not about alternatives to alodyne, or about
primers -- it is how to alodyne large sheets without having huge
quantities of chemical!!

Unfortunately, IMHO, there is no alternative. As you know, Ed, I had an
alodyne tank setup in CA, which I made up, using a lye solution for etch
and a companion tank for the alodyne.

I got the lye from the supermarket and the alodyne powder from a plater.
For best reaults, the lye should be at 120 dg f. Etch for 5 minutes,
wash, alodyne for 10 min., wash.

Using lye ( sodium hydroxide ) for an etch is a disasterous choice.
The treatment you describe will more than remove all of the alclad
from the sheet and leave you worse off than when you started.

O-ring

I'm reminded of the time a student in an automotive class
put his engine block in the caustic solution over the
weekend. It works great on a cast iron block. Removes all
the crud, paint, etc.

However, on Monday, when he opened the tank to remove his
block, all he found was a few bits and pieces plus the
cylinder liners.

Caustic solutions and aluminum are NOT a good mix. Even an
aluminum engine block can be "eaten away". Think what it
will do to a thin aluminum skin...

John