Priming wood panels with acrylic gesso or oil grounds

Do I need to seal and prime unprimed panels? Yes.

Ampersand offers several ready to use sealed and primed panels, but for artists that prefer to prepare their own painting panels, enjoy working with a natural wood look, or need strong support for encaustic, collage, or mounting, Ampersand also offers three unprimed wood panel options: Hardbord, Unprimed Basswood, and Woodpanel.

Commonly, artists ask us if unprimed wood panels need to be sealed.

The answer is yes. The only exception is if you are working with encaustics, otherwise, it is strongly recommended to seal all unprimed panels to create a barrier between the wood and the ground. When using acrylic grounds and paints, this barrier isolates the wood tannins and lignin to prevent them from seeping into the priming and painting layers which can cause your paint film to yellow over time. This yellowing phenomenon is called Support Induced Discoloration, or SID, and it is prevented by properly sealing the surface before use. When using oil or alkyd grounds and paints, sealing the panel reduces the panel’s absorbency and prevents moisture absorption and warping.

Jump to: How to prime wood panels with oil grounds

How to prime wood panels with acrylic gesso

Materials List:
Ampersand Hardbord, Unprimed Basswood, or Woodpanel
Gloss acrylic medium (such as Golden’s Gloss Medium)
Acrylic gesso
2"-3" flat bristle brush
Small foam roller (optional)
Sanding block with fine 400/grit sandpaper
Painter's tape (optional)

Step 1: Size and Seal the Wood
When using acrylic gesso as the ground layer, sealing a wooden panel is recommended to protect your painting from yellowing due to support-induced discoloration.

The same number of applications should be applied to both the front and back of the panel to ensure a balanced panel that resists warping.

Using a 2"-3" flat bristle brush, apply the sealer to the front of the panel. When dry, apply it to the back as well. Allow first application to dry completely and follow with an additional coat. Do not sand between layers of the sealer. Before applying acrylic gesso, allow to completely dry so that the sealer 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 to show.

If you prefer to paint the panel’s cradle, 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 to protect them while painting.

Step 3: Apply the Acrylic Gesso
Acrylic gesso is a flexible liquid ground that protects and gives "tooth" to wood panels, which promotes good paint adhesion. It comes ready-to-use and can be applied with a brush, roller, putty knife, or even sprayed on. Follow the directions provided with the gesso product that you are using for product-specific information. For this example, we will share instructions of application using a brush and roller.

Using a 2"-3" brush, begin by working the gesso back and forth with the brush in one direction and then in a cross direction with a little pressure so that the gesso penetrates the panel better. Remember to gesso both the front and back of the panel.

If you sealed the panel’s cradles, you could apply gesso to the cradles at this time.

Step 4: Finish
After the first coat of gesso is dry, smooth out any rough spots with light grade sandpaper. Apply a second coat of gesso with the foam roller for a more even application, (a brush may also be used if you do not have a foam roller). Allow it to dry and then sand again. For best results, apply a minimum of 2 coats of gesso and sand in-between. Subsequent layers of gesso will produce an even smoother painting surface. Follow the directions provided with the product that you are using for the recommended number of coats. For spray-application, you may need to apply more than 2 coats to achieve a painting surface similar to a brush application.

For each coat of gesso to the panel surface, apply the same number of applications to the back.

Once the final gesso coat is dry, your panel is ready!

How to prime wood panels with oil grounds

Materials List:
Ampersand Hardbord, Unprimed Basswood, or Woodpanel
Oil or alkyd painting ground
Odorless mineral spirits
Foam roller (with a short nap)
Large putty knife/scraper or 2"-3" Flat bristle brush
Sanding block with fine 400/grit sandpaper
Painter’s tape to protect cradles (optional)
Sealers (select one):
PVA size (Polyvinyl Acetate size intended for oil painting)
Professional acrylic gesso
Diluted alkyd medium (such as Gamblin’s 3-in-1)

Step 1: Size and Seal the Wood

Unlike canvas or paper, wood panels do not need to be sized to protect them from the acids in oil painting grounds, mediums, and paints. While you can apply oil or alkyd ground directly to a wooden panel surface, Ampersand recommends the following options for preparation to reduce the panel’s absorbency and prevent moisture absorption and warping.

The same number of applications should be applied to both the front and back of the panel to ensure a balanced panel that resists warping.

Seal Option 1: PVA Size

NOTE: Using a 2"-3" flat bristle brush or large putty knife, apply PVA size to the front of the panel. Allow to dry completely and follow with an additional coat. For each coat on the face of the panel, apply a corresponding coat to the back of the panel as well. Do not sand PVA size applications.

The dark wood of the panel will show through PVA size and sometimes show through thin applications of oil primer. If you prefer a brighter white surface, apply 3-4 coats of professional acrylic gesso over the PVA size before applying your oil ground.

Seal Option 2: Acrylic Gesso

NOTE: Using a flat bristle brush, apply 3 or more coats of professional acrylic gesso to the face of the panel, repeating the process on the back of the panel as well. Allow the acrylic gesso to completely dry. You can lightly sand the gesso surface if desired before applying the oil or alkyd ground.

Be sure to follow the manufacturer’s guidelines for any specific recommendations for diluting and applying their acrylic gesso.

Seal Option 3: Diluted Alkyd Medium

NOTE: Do not use option 3 if mounting paper or canvas/linen to the panel.

Use a brush or large putty knife to apply diluted alkyd painting medium to the face of the panel. Allow it to soak in for 2-3 minutes. Wipe away excess medium with a lint-free cloth and allow the panel to dry overnight. Repeat this process on the back of the panel.

NOTE: Apply a second coat and allow it to fully dry if you wish to paint with oils directly on the diluted alkyd medium layers. Do not sand the layers of medium.

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 to show.

If you prefer to paint the panel’s cradle, be sure to seal the cradle with one of the recommended methods 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 to protect them while painting.

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 sealed and dry 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 out the application with a soft brush or foam roller with a short nap. This will result in a thin, uniform coat.

When the first coat of oil painting ground is completely dry, you can sand the surface with a sanding block using light grade 400/grit sandpaper. A second ground coat can be applied after the first coat is dry.

Repeat this process on the back of the panel.

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 oil or alkyd ground 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 as needed 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 ground you select. The more coats of ground or primer that are applied, the smoother the surface will become. It is recommended to apply several thin applications rather than a thick application for proper drying.

Repeat this process on the back of the panel.

If you sealed the panel’s cradles, you could apply oil ground to 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!

Go back