Posted by Robert beverly on August 15, 2002
Rick Sacks
I am fixing to start applying leaf on aluminum...cast pieces....Are there any special coatings or methodology that I should apply?....These will be exterior...
and of course a brilliant finish is my goal!
Thanks in Advance!
Robert BeverlyRob, there definatly are issues to be concerned with. The main issue is electrolisis...what happens when water runs across dissimilar metals. The aluminum needs several coats of paint before applying gold size to form an insulating barrier between the metals. I use zinc chromate as a primer often, and assume metal content in it and don't even count it as one of the layers.
I have some places with Gemini cast aluminum letters with gold size airbrushed on and gilded and the aluminum is actually erroding.
Rick SacksRick
Howdy and thanks for the quick reponse....so what do you mean by airbrushing the gold size on?...and my next question would be...you say..."assume metal content in it and don't even count it as one of the layers"...what do you mean?
Thanks
The letters I was doing were cast and over an inch thick with rounded sides. I found it easier to spray the size than to brush it, so I used my air brush because it was more in proportion to the scale of the letters.
The part about metal content was referring to the zinc chromate primer.
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