What are paint mediums? [ A guide for beginners ]

Confused about what paint mediums are? I sure was when I started.

I didn’t realize the word medium was used for 2 things. And I had no idea what a paint medium was for. (That’s how I ended up with a slow-drying medium! Definitely not something an alla prima painter needs.)

So in this beginner’s guide, I will break down everything you need to know about paint mediums, what they are, and how to use them.

And here’s some BONUS content for you. Click here to download your QuickStart Guide to Oil Painting. It’s free. Easy to read. And designed to get you painting fast.

Know the difference between ART and PAINT mediums

These are 2 different things.

Art mediums are the things we use to create art.

Watercolour, oil, pastel, pencil, sculpture, clay etc., are examples of art mediums. Mixed media means it’s a mixture of more than one medium.

When you go to an art gallery, the type of medium the artist used is usually displayed on the card with the title and name of the artist. Examples: oil on canvas, acrylic on wood, watercolour on paper.

Paint mediums are substances that are added to paint

These will change the paint’s flow, consistency, texture, sheen and even drying time. This will not just make your paint more versatile, it will affect the final look, too.

While all paints can be used straight from the tube, adding a medium can allow for more creative possibilities. They can expand your paint’s range and increase the number of effects you can achieve.

Try experimenting with the different mediums. See what different results you can come up with. This is how you can find your unique and personal style.

Be sure to buy the right paint medium for your art medium!

You can buy paint mediums for oil paint, acrylic and watercolour paint. Don’t mix them up.

How much medium do you add to paint?

It’s important to follow the instructions for each product. For some paints, if you dilute them too much, you will break their adhesion capabilities. This will result in a paint layer that is prone to cracking and flaking.

For oil paints you can vary the amount but it’s generally advised to not go beyond 30% of the volume of the paint.

For acrylic paints, some mediums are made with formulas that allow you to add a higher ratio of medium to the paint. Just follow the instructions for each product.

Note: Acrylic paint can be thinned with water, but if you thin the paint too much it will weaken the paint film. This may result in the paint peeling and chipping off in the future. Use specially formulated paint thinners if you want runny paint.

The fat over lean rule for oil paints

This rule is mostly for the Classical or Flemish style of painting. In this oil painting process, the artist paints in thin paint layers, with each subsequent layer getting more and more “fat” —  fat here means oil or medium.

This is to keep the paint from cracking. The different layers will be drying at different times, so the oil or fat will keep the top layers less brittle.

When you are oil painting in the alla prima method, you generally don’t have to worry about the fat over lean rule.  This is because we aren’t painting in layers.

But the fat over lean rule is good to remember because in the alla prima method, you start with thinned paint and add more medium as you go. It’s hard to get paint to stick on top of thick paint, so adding medium helps. But remember to not go over 30% of the volume in your mixture, or the paint will lose its adhesive qualities and ability to bond.

Mediums for oil paint

In oil painting, you can add hardening oils like linseed, safflower, walnut or poppy oil to paint. These are used in the manufacturing of paints so they are a natural fit. They dry at different speeds, with linseed the fastest and poppy oil the slowest.

Then there are specialty mediums that will change the flow, texture sheen. Each brand of paints usually has their own proprietary line of mediums.

The different types of oil paint mediums

Impasto and oleopasto mediums add body to the paint. Both allow you to make strong marks and textures that keep their shape even after the paint dries. The only difference between the two is that Impasto dries with a glossy finish and Oleopasto dries matte. They also speed drying time.

Cold wax medium is made with beeswax.  It creates a paint that is dense, dries hard and with a matte surface.

This medium creates an effect that emulates encaustic paint but without the toxicity. Encaustic painting needs a well-ventilated space to work. This is because you need to heat beeswax to soften it and that can lead to toxic fumes. But you don’t need to heat cold wax mediums so it’s perfectly safe to use.

Slow-drying mediums are for painters who want their paint to stay blendable (open) for days or weeks. This is usually people who paintportraits, big paintings, or very detailed paintings. You don’t need this for small alla prima paintings, which are all about finishing a painting in one sitting.

Fast-drying mediums are for artists who want the paint to dry fast. This includes alla prima and plein air artists, or artists who are trying to finish their work before a big show (deadlines!) Look for Liquin by Winsor Newton, or mediums labelled Alkyd.

Mediums that add gloss. Stand oil is thickened linseed oil and it makes paint glossy. A traditional oil paint medium is 50% stand oil with 50% turpentine.

Mediums that reduce brushstrokes. These will cause the brushstrokes to flatten or level out and appear with less peaks or shadows. Some mediums that do this are stand oil (thickened linseed oil), Liquin by Winsor Newton, and Gamblin’s Neo-Megilp.

Mediums that enhance the brushstrokes stop the paint from leveling, keeping strong brushstrokes, body or peaks. They are impasto mediums, cold wax medium, and some proprietary brands.

Solvent-free mediums. Please note, some pre-made mediums might include OMS in their formulas. If you want to paint solvent-free, use mediums marked as such, or the plain hardening oils.

Mediums for acrylic paint

Acrylic painters have the widest variety of mediums to paint with. They can be used to create a myriad of textures, transparencies, and sheens (how matte or shiny a paint surface will be).

Mediums that will change the sheen of paints:

• Gloss Medium — will enhance the shine and brightness of acrylic paint.
• Matte Mediums — will create a non-reflective finish on a painting.

By mixing the above mediums together in different ratios, you can achieve a range of finishes, from semi-gloss to satin to completely matte.

Glazing Medium is added to acrylic paint to make it more fluid and transparent. It can enable artists to create delicate glazing effects.

Gel Mediums add body and texture to paintings. They are available in both liquid and heavy body consistencies and comes in many sheens: matte, gloss, or semi-gloss. Gel medium can also improve the adhesive properties of paint. This is why it’s a popular glue for collage artists.

Heavy Body medium makes the paint thicker and creates visible brushstrokes. This can add depth and texture to a painting.

Modeling Paste is thicker than gel medium. This heavy white gel is perfect for creating 3D effects in your paintings. (Paintings with pronounced 3D surfaces are called reliefs.) Modeling pastes thicken the paint so you can almost sculpt with it. You can also use it to embed objects right into the surface.

Texture Gels such as pumice, sand, beads and glass mimic various textures and can create unique effects.

Retarding Medium is used to slow down the drying time of acrylic. This makes the paint behave more like oil paint: it allows for smoother blending and color mixing on the canvas.

Open Acrylics are a type of paint that contain a medium that extends their drying time. This makes them suitable for blending effects and act more like oil paints, too.

Flow Improver is used to thin the paint for techniques like washes or for painting over large areas. While water can also be used to thin acrylic paints, flow improver is a better option. Too much water can break down the adhesive ability of acrylic paint, causing it to flake or crack if too thin.

Pouring Mediums are used to create fluid art. This is art that is poured onto a canvas or other surface and allowed to flow and mix together. They usually reduce the appearance of brush strokes and create a glossy finish when dry. ( Liquitex Pouring Medium, Golden GAC 800, and Floetrol are some examples).

Watercolour mediums

Just like with the other mediums, watercolour mediums are used to control the flow, sheen and transparency of watercolor paint.

Gum arabic is the binder that is used in the manufacturing of most watercolour paints. It is water-soluble. When you use gum arabic as a medium, it increases the gloss and transparency. It can also slow the flow of the paint allowing for better control over the paint.

Gum arabic can also make it easier to correct your mistakes. You can lift the colour more easily from the paper. But as in all watercolour, some pigment will remain and stain the paper,

Ox gall is a wetting agent that allows the paint to flow more smoothly across the paper. (You can get vegan formulas.)

Retarders will slow down the drying time of watercolor paint, allowing the artist more time for blending.

Texture mediums can be used to create interesting textures and effects such as granulation, stippling, and impasto. There are also mediums that can add a 3D texture to your paintings.

Iridescent Medium will add some sparkle with a light iridescent sheen. 

#DumaDoArtTip:

You never know what you will like! So try them all.

That’s another reason painting small is so fun. You can try a new art supply with every painting. Super fun.

Want to learn to oil paint?

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