Raw Aluminum
Often found in hardware and building supply stores. Comes in a wide range of types and thicknesses, and may have surface treatments. See Painting on Metal: An Introduction for more detail.
At minimum, scuff the surface, degrease with isopropyl alcohol, then use a commercial DTM (Direct to Metal) or Bonding Primer suitable for aluminum and able to accept waterbased paints. Always follow the manufacturer’s recommended preparation.
Since commercial primers may yellow, applying 1 or more coats of acrylic gesso on top of the primer will provide a whiter ground.
Oils and Acrylics can be painted directly on this preparation.
For watercolors and dry drawing media, an additional acrylic ground appropriate for each media should be applied before painting.
Hi, when you say a bonding primer what do you mean? Because I cannot find anything like that for sale in art stores. Is there a particular product I could use? Is a bonding primer like a synthetic size? For instance would artist grade pva do the job?
Say if I wanted to coat it with and oil primer how would I go about it?
Many thanks
Tighe
If painting with acrylics on raw aluminum, we recommend scuffing with fine sandpaper and degreasing with Isopropyl alcohol, then applying a commercial Direct To Metal Primer, designed for latex paints, that you would purchase at a house paint store. If painting with oils on top of raw aluminum, we found in our testing that the oil paint adheres rather well directly on the aluminum if scuffed and degreased first. This also holds true if you would like to apply and oil ground directly on the aluminum. The key is the scuffing and degreasing first. We hope this is helpful and if you have any further questions, feel free to email us at help@goldenpaints.com.