Don't forget the aluminum primer -- I think Wal used a yellow zinc chromate 
prime coat ahead of the finish coat.

Fred Street -- Minneapolis
S/V Oceanis (1979 C&C Landfall 38) -- on the hard in Bayfield, WI   :^(

On Jul 10, 2012, at 7:15 PM, dwight veinot wrote:

> Unless you guys have some special aluminium alloy then the minute you sand
> or polish the mast or boom down to bare alloy then that's the minute that
> oxidation of the surface starts, and that new oxide layer forms an
> impervious  protective layer against further corrosion, chemical anodizing
> can change the surface colour but the protective layer so formed is not much
> better than that formed on clean aluminium just left in contact with air,
> and that passive layer forms very quick.  So sand it and coat it, 2 part
> polyurethane is really good and one part is OK too, seems that's what Wally
> used and he said it's fine after all this time, pay attention and use the
> proper tie coat on the clean metal if one is required by the top coat you
> choose.
_______________________________________________
This List is provided by the C&C Photo Album
http://www.cncphotoalbum.com
[email protected]

Reply via email to