I have a truck bed that is galvanize metal . I was painted black then purple the paint is turning loose in spots . I am going to sandblast it to bear metal. how do I prep it to get the paint to stick to it. I have never painted galvanize metal before thanks
clean sand the grit can vary depending what you are going to spray on top of it I would look up the tech sheet on what primer/paint you plan to use and follow their directions the vinegar will remove any 'white rust" alkyd/oil paints generally do not like galvanize
Acid bath (vinegar) and, if you sand, USE A RESPIRATOR, that galvanized coating is not good for you if you breath the dust, or the fumes from welding or burning. Leaving dust on exposed skin for long periods can result in skin irritations. Check with a paint manufacturer and see if you can paint over the galvanized with a zinc chromate primer. It should bond with the galvanized material then you can paint over that.
Vinegar to strip it Look into it but what about low pressure blasting with walnuts or baking soda? Epoxy primer or an etching primer And your top cost of paint Latex paint and primer adhere to galvanize but are not particularly durable if the bed is going to be used for work. Is there a galvanized paint, or maybe powder coating?
DID EVERYONE NOT SEE "GALVANIZED' IN THE TEXT??? maybe you need to re-think your advice to the original poster
Zinc Chromate primer..........there are restrictions, but I think you can still obtain trivalent version to passivate the zinc
I would prep galvanized flashings and gutters with a product called Metal Etch or metal prep or vinegar. That seemed to hold up well. But than again never used it on auto parts or anything that needed a fine finish
Yes I did that’s why I recommended what I did. What do YOU recommend? Instead of trying to make it out others are wrong ?
I gave good advice for the amount, or lack of information given. You are welcome to improve on my statement, if you are able. Thanks Clemens .
Reading a tech sheet is standard practice for any paint The epoxy I use recommends a 120 - 180 grit scratch on galvanized The vinegar will clean galvanize It’s not listed in the tech sheet for the product I use but is a standard home remedy for cleaning galvanized On new cars we use an etch primer to handle the galvanize issue . Not knowing the product being used is the reason for generic answers The question was answered from the limited info given More specific answeres can be given with more info.
He wants to paint it, presumably to protect it from the elements or to match the rest of his vehicle, he didn’t say that he wants to save the galvanising........ He also says that he wants the paint to stick ! .
The paint is not the issue It’s what is sprayed under it Only industrial products are used straight over galvanize. Automotive paint manufacturers recommend either an epoxy or self etching product under their top coats
You could use a product that's actually made for the purpose. Galvaprep reacts with zinc to form a zinc phosphate coating that paint will bond to more effectively than vinegar which forms zinc acetate on the surface. If you have it sandblasted by the normal means then you won't need to worry about the zinc since it won't be there anymore. Once treated (or blasted) I'd prime it with epoxy.
Thank you Anthony, nothing bugs me more then when people answer a thread dismissing what advice has been given as wrong, but not adding a damn thing that’s useful. Yes and that’s why after stripping and cleaning the surface ( low pressure sandblasting with low abrasive medium, steel wool, somewhat fine sandpaper and being gentle, all will work) Epoxy primer or etching primer THEN YOUR TOP COAT OF CHOICE Latex sticks or adheres best to galvanized but is not the only paint that will work. If he wants single stage AFTER prepping and priming/sealing the serface he can paint it with what ever he pleases!
Guys!, he said he has a truck bed made out of galvanized steel, why aren't we asking for pictures?, I'll bet it's something pretty horrific.
After stripping use vinegar to clean the surface there is a product called XIM primer, it's available in clear & white and designed for ferrous & non ferrous materials, it promotes adhesion. I have seen it used on glass,porcelain and chrome and when painted it doesn't chip or flake. HRP
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