Zinc is a sacrificial metal. It has higher reactivity then steel or
iron. As such, it corrodes first. When the zinc is gone, the steel
then starts to rust. That's why outboard motors all have sacrificial
zinc bolted onto them.
The safety of using zinc is limited. It is limited by how well it is
placed in relation to the corrosion circuit. It is also limited by the
quantity of zinc applied. In the case of sprayed coatings, it is also
very limited by the insulating qualities of the coating carrying the
zinc.
Wax-oyl seems to be one of the best products on the market. I've been
in cars that were wax-oyl treated when new, 20 years ago, and the
coating is still soft, oily, and there is no corrosion.
Beware, most other coatings are thick and tend to not flow into the
critical seams. Wax-oyl does. A coating that does not flow into the
seams will eventually get water in the seam (water flows remarkably
well), and then rust away.
>>> James Carruthers <j.carruthers@rave.ac.uk> 06/07/03 01:53PM >>>
Listers,
I have been reading through the extensive set of receipts that the guy
who restored my Spit. My first question is about zinc phosphate... the
chassis, and also the body, seems to have been blasted with this...
what
does that mean? I know its good for rust prevention - but what does it
actually do?
2nd... I need to do something with the insides of my wheel arches -
currently theyre just straight painted... what's considered the best
for
this?
3rd... Same as question 2 - but with the underneath of the car... Im
guessing its going to have to get wax oyled - but are there any other
preventative measures? Something like POR15 sounds good - but as far as
I am aware this is for bare metal...
-----------------------------------------------------
The information contained in this communication may be confidential, is
intended only for the use of the recipient named above, and may be legally
privileged.
If the reader of this message is not the intended recipient, you are hereby
notified that any dissemination, distribution, or copying of this
communication, or any of its contents, is strictly prohibited.
If you have received this communication in error, please re-send this
communication to the sender and delete the original message and any copy of it
from your computer system. Thank you.
-----------------------------------------------------
<<<<GWIASIG 0.07>>>>
/// spitfires@autox.team.net mailing list
/// or try http://www.team.net/cgi-bin/majorcool
/// Archives at http://www.team.net/archive
|