Priming Wood Panels With Oil Grounds
A wood panel is a better painting substrate because it is less susceptible to expansion and contraction than flexible supports, like canvas. The movement of these flexible supports can result in cracks and damage to the artwork created on them.
Ampersand offers several ready to use sealed and primed panels, but for artists that prefer to prime their own painting panels, enjoy working with a natural wood texture, or need strong support for encaustic, collage, or mounting, Ampersand also offers three unprimed wood panel options: Hardbord™, Unprimed Basswood, and Birch Wood Panel.
Commonly, artists ask us if unprimed wood panels need to be sized. The answer is yes.
All raw wood panels should be sized properly before applying ground applications, regardless of whether you use acrylic polymer dispersion “gesso” or oil painting ground.
Ampersand Hardbord, Unprimed Basswood, or Birch Wood Panel
Golden® Gloss Medium or Gamblin® PVA Size
Oil or alkyd painting ground
Odorless mineral spirits
Foam roller (with a short-nap)
Sanding block with fine 400/grit sandpaper
Large putty knife or 2″-3″ Flat bristle brush
1″- 2″ painter’s tape (optional)
Step 1: Size and Seal the Wood
A size is a thin solution (often a weak glue) that is brushed directly onto a support. For oil or alkyd primers, sizing raw wood is done for the sake of isolating the wood from the ground for an acid-free painting surface and to mitigate potential warping in the future.
Because of the lower density of plywood panels like Basswood and Birch, the application should be applied to the front and back to ensure they are fully protected. Due to the high density of Hardbord, this panel only requires sealing the front of the painting surface.
The products we recommend to size wood panels are:
Golden® Gloss Medium OR
Gamblin® PVA Size
Using a 2”-3” flat bristle brush, apply the acrylic medium or PVA Size to the front of the panel. If using a plywood panel, apply it to the back as well. Allow to dry completely and follow with an additional coat. Do not sand between applications. Before applying the oil painting ground, allow the sealer to completely dry so that it can coalesce into a uniform film for maximum protection.
Step 2: Protect and Prepare the Cradle
Ampersand unprimed panels are available with wood cradles in various depths. Artists may choose to paint the cradles or leave them untouched and allow the natural beauty of the wood cradle to show.
If you prefer to paint the cradles, be sure to seal the cradle first, as it is also constructed of unprimed wood. Or, if you choose not to paint the cradles, cover the sides of the panel with painter’s tape, up to the edge of the surface, to protect the wood from paint and oil ground.
Step 3: Apply the Oil Painting Ground or Primer
If recommended by the manufacturer, you may thin alkyd or oil primer by mixing in a small amount of odorless mineral spirits. You can test to see if it is the right consistency by picking up the primer with a palette knife or putty knife and shaking it gently. If it falls from the knife like soft butter, it is ready to use. Oil and alkyd primers can be applied with either a large putty knife or a large stiff bristle brush.
When priming with a putty knife, begin by placing a portion of the primer in the center of the (already sized) panel. Spread it across the entire panel surface. Clean the putty knife and run it over the ground to smooth and even out the ground application. You can also even the application with a soft brush or foam roller with a short-nap. This will result in a thin, uniform primer coat.
When the first coat of oil painting ground is completely dry, you may lightly sand the surface with a sanding block using light grade 400/grit sandpaper. A second coat of primer can be applied after the first coat is dry.
When priming with a brush, use a large bristle brush, at least 2″-3″ wide (proportionate to the size panel you are using), and apply the ground or primer with quick alternating strokes, working it well into the surface. After evenly distributing the oil primer over the entire surface, finish by going over it lightly with a clean brush, carefully in straight lines, or use a short-nap foam roller. Let the first coat dry, then sand and apply a second coat. At least two coats of ground or primer should be applied but be sure to follow the manufacturer’s instructions for the primer you select. The more coats of ground or primer that are applied, the smoother the surface will become.
For plywood panels like Ampersand’s Unprimed Basswood or Birch Wood Panels, follow the same instructions, but for each application to the panel surface, apply the same number of applications to the back.
If you sealed the panel’s cradles, you could prime the cradles at this time.
Step 4: Finish
Eliminate any unevenness on the finished primed surface by lightly sanding the panel after it has thoroughly dried. The finished primed panels should be allowed to dry completely at room temperature before painting. If you prepare several panels at a time, then you will have stock on hand that is dry and ready to paint when needed.
Once the final coat is dry, your panel is ready!