Pre-treatmentrs for painting on Zinc?
Pre-treatmentrs for painting on Zinc?
(OP)
Can anyone help we have die-cast zinc components (Zamak 3) which we would like to paint. Are there specific pre-treatments we should be using and can anyone recommend any particular paint companies that may specialise in paints for zinc.
Thanks for your help
Regards
T
Thanks for your help
Regards
T





RE: Pre-treatmentrs for painting on Zinc?
For resin-acid wash primers incorporating zinc chromate pigment, see DOD-P-15328 and MIL-C-8514. Both are available at the DoD’s ASSIST site: http://assist1.daps.dla.mil/quicksearch/
Also ‘Paint No. 27 Basic Zinc Chromate-Vinyl Butyrol Wash Primer’ -- Steel Structures Painting Council Specification.
See also
ASTM D2092-95(2001)e1 Standard Guide for Preparation of Zinc-Coated (Galvanized) Steel Surfaces for Painting. http://www.astm.org/
MIL-C-17711 Coatings, Chromate, for Zinc Alloy Castings and Hot Dip Galvanized Surface.
MIL-T-12879A Treatments, Chemical, Prepaint and Corrosion Inhibitive, for Zinc Surfaces.
Metal Finishing Guidebook & Directory and Metal Finishing Organic Finishing Guidebook & Directory. Both are included with a subscription to Metal Finishing magazine. http://www.metalfinishing.com
As for painting, it depends upon the parts’ application and available painting equipment (wet spray, powder coat, ovens, etc.). An epoxy base coat and polyurethane topcoat is common for outdoor applications. I have also heard that it is possible to (anodically) ecoat diecast alloys without pretreatment, but I am not familiar with the process.
RE: Pre-treatmentrs for painting on Zinc?
Regards
T