What is Gesso: Painting Surface Preparation for Stunning Results

For many artists, the key to a successful painting lies in the preparation of the surface. One crucial step in this process is the use of gesso—a versatile primer that can transform the way your paint interacts with the canvas, wood, or paper. In this comprehensive guide, we’ll explore the ins and outs of gesso, its benefits, and how to use it effectively on various surfaces. This essential read aims to provide artists with the knowledge needed to perfect their craft and create stunning works of art.

What is Gesso?

Gesso is a white, thick, paint-like substance made from a combination of chalk, gypsum, or marble dust, mixed with a binder like acrylic polymer or rabbit-skin glue. Its primary purpose is to prepare and prime surfaces for painting, providing a consistent base that improves paint adhesion and ensures a smooth, even application. In this sense, it can be considered as a foundation for an artwork.

Applying a layer of gesso acts as one of the first stages in the process of creating a painting. It acts as a barrier between the surface and the paint, providing a blank canvas for artists to work on with more vibrant colours that won’t be absorbed by the painting surface. Gesso also helps to reduce paint absorption, allowing you to use fewer layers of paint and save time in your artwork.

When should you apply gesso to a surface?

Gesso should be applied to a surface after the surface has been sealed. Seal the surface first with GAC-100, to create an impermeable base. The application of gesso acts as the second and final step in the surface preparation process. After the gesso has dried, artists may choose to create an underpainting as a base for their artwork.

If you have bought a canvas or a wooden panel that is labelled with ‘universally primed’, then it means that the surface has been sealed and usually around three coats of gesso will have been applied. In this case, it’s not necessary to apply more gesso to the surface. However, artists often opt to add a couple of extra coats to achieve a smoother surface finish.

Make sure that if you’re working with water based paints like acrylic or watercolour, that you use a canvas labelled ‘universally primed’ rather than ‘oil primed’. However, if you work with oil paints you can work on an oil primed surface.

Types of gesso

Universal or acrylic gesso primer

This type of gesso is made out of modern polymer binders (acrylic emulsions) and can be used with water-based paints and oil paints. The advantage of this type of gesso is that it’s flexible and can be applied to a variety of surfaces, such as canvas, paper and wood.

There are lots of popular acrylic gesso primers on the market. Here are some of the best ones available to artists:

• Liquitex Professional gesso: This is the standard gesso used by professional and beginner artists alike. Paint three coats to prime the surface.
• Michael Harding acrylic primer: This primer is non absorbent and prevents paint from ‘sinking in’ to the surface. Paint appears more luminous on surfaces primed with Michael Harding gesso.

Oil based primer

This is the traditional primer, that oil painters have used for centuries. Oil based primer is made out of animal skin glue, usually rabbit skin, and white chalk. It takes a longer time to dry than acrylic gesso, so it can be difficult to work with. Oil primer should only be used with oil paints, as it will provide an unstable surface for water based paint like acrylic.

Which mediums can you use gesso with?

Gesso can be used as a primer beneath a multitude of mediums. Here are some tips and use cases with each art medium…

Oil paint

Artists will commonly prime their surface with gesso before starting an oil painting, even if their canvas or panel has been bought primed and ready. By applying an extra few coats of gesso and sanding the layers, artists can opt to work on extra smooth surfaces.

You can use oil based gesso primer with oil paints, but you can also use acrylic based gesso as the first layer.

Acrylic paint

Use acrylic based gesso with acrylic paint. Most acrylic paints can be applied directly to the surface, including paper, wood and canvas. However, a sealant like GAC-100 and acrylic gesso will add an extra layer of protection and keep your artwork looking bright and colourful for years to come.

Watercolour

Regular gesso isn’t suitable for watercolour painting, as it is not absorbent enough. However, you can buy watercolour ground, in order to prepare paper or canvas for watercolour painting. Of course, if you’re already using watercolour paper, you shouldn’t need to add additional ground to the surface. But watercolour ground can be used to make canvases and paper that is not absorbent enough suitable for painting with this fluid medium.

A ground like Golden Absorbent Ground will provide absorbency and flexibility to any surface, to make it suitable for watercolour painting.

Alternatively, you can buy primed watercolour canvases from Fredrix that are ready to paint onto.

Sealing Surfaces with GAC-100

Before applying gesso to raw wood, linen, or cotton, it’s recommended to seal the surface with an acrylic sealer like GAC-100. This step makes the surface impermeable, ensuring that no moisture or resins from the raw materials can seep into the surface. You can sand the coat of GAC-100, once dry, then proceed to apply the coats of gesso.

How many layers of gesso should you apply?

The general rule of thumb is to apply three coats of gesso after you have sealed the canvas with GAC-100. Wait for each layer to dry and sand before applying the next layer.

How long does it take gesso to dry?

It takes around half an hour for gesso to dry. However, this can depend on the brand of gesso, thickness of the application and the amount that the layer has been diluted. Once the final layer has been applied, wait around 24 hours for the gesso to fully dry and set before starting the painting.

Benefits of Using Gesso

1. Creates a barrier: Gesso acts as a barrier between the paint and the surface, preventing the paint from soaking into the fibers of the canvas or wood, which could cause deterioration over time.
2. Enhances paint adhesion: Gesso provides a slightly textured surface, improving paint adhesion and making it easier to apply subsequent layers.
3. Provides a consistent base: Applying gesso ensures a uniform, non-absorbent surface, allowing for better control over the paint and more predictable results.
4. Increases brightness: The white colour of gesso backlights and therefore increases the vibrancy of transparent or semi-transparent colours, making them appear more vivid and luminous.

Using Gesso on Different Surfaces

• Canvas: For both linen and cotton canvases, applying a thin layer of gesso is essential to seal the fabric and prevent paint from seeping through. Allow the gesso to dry completely before starting to paint, ensuring a stable and consistent surface.
• Wood: Gesso can be applied directly to sanded, clean wooden surfaces. It’s crucial to apply multiple thin layers, sanding lightly between each layer, to achieve a smooth and even surface.
• Paper: When working with oils or acrylics on paper, applying gesso can prevent buckling and improve the longevity of your artwork. Make sure to use a thin layer to avoid making the paper too stiff.

How to Apply Gesso: Step by step

1. Clean the surface. Either wipe it clean with a lint free cloth, or use a lint roller to remove extra dust.
2. Gesso-ing can get messy! I always put down a tablecloth to prevent furniture from getting stained.
3. If you’re painting on unprimed paper, wood or canvas, you will need to seal the surface first with GAC-100. Pour a little of the product into a dish and use a stiff brush to apply evenly to the surface. Apply three coats of GAC-100, waiting for the layers to dry before the next application. Sand between applications. Make sure to clean GAC-100 from your dish before it dries, as it is difficult to remove.
4. To apply the gesso, make sure to follow the manufacturer’s instructions for information about dilution. For instance, some brands of gesso will advise that you dilute the mixture and some will advise that you paint with straight gesso.
5. Pour a small amount of the gesso into a clean dish, then get a large, wide, stiff brush and start applying the gesso evenly. Paint in one direction, either horizontally, or vertically. Make sure to cover the sides of the canvas or panel.
6. Wait around 30 minutes for the gesso to dry. Then use fine grained sanding paper to gently sand the surface. Make sure to wipe away any sanding residue with a damp cloth. Wait again for the panel to dry before applying the next layer.
7. Repeat this process twice more. Make sure to wait around 24 hours after you have applied the final coat of gesso before painting.

Finally

Understanding the proper use of gesso is essential for artists looking to create high-quality, long-lasting work. By taking the time to prepare your surfaces with gesso and sealing them when necessary, you’ll ensure better paint adhesion, enhanced colour vibrancy, and improved longevity for your artwork. So, grab your gesso and start priming—your masterpieces await!