Your quick guide to thinning oil paints

By Nicole Tinkham

One thing that holds many artists back from exploring the incredible world of oil painting is the simple fact that they don’t know where to begin. Oil painting is quite different from watercolors and acrylic paint. Even your brushes need to be washed a special way! But it’s not rocket science. The main concern with oil paint tends to be how to thin the paints and understanding the various mediums out there to help you do so. If you’re not used to these mediums and solvents, it can be quite overwhelming. In this quick guide, you’ll learn about solvents and mediums, how to mix them into your paint to thin it, and the golden rule of layering.

#1: Choose your thinner

Solvents: These will dilute oil paint and can also be used to clean your brush. You can use turpentine for this which will create a watery mixture. Keep in mind when using a solvent to work in a well-ventilated room and look for options which are low-odor. Also be sure you’re getting solvent at an art supply store as the solvent in hardware stores is not the same!

Mediums: There are a ton of mediums you can use with oil paints, each one having a different effect. Some of these mediums thicken paint and others thin the paint. Just be sure you know exactly what it does before using it in your painting. Get your guide to oil paint mediums here.

#2: Mixing the paint

For your first layers in an oil painting, you’ll want to be sure to thin down the paint. We’ll get into the “thick over thin” rule next but first let’s talk about HOW to thin oil paint for those under layers. You’ll simply be taking a blob of your oil paint and placing it on your palette. Then you’ll add your thinning agent of choice to the paint. For your first few layers, use just a dime-sized amount of paint and a good amount of thinner. Blend these well with a palette knife and you’re ready to paint!

#3: The golden rule

Thinner colors should be applied first as they dry faster. Thicker (less thinned) oil paint goes on as top layers. If you don’t apply oil paint in this order, it can result in cracked paint since the thinner colors dry so quickly. You also want to make sure each layer is completely dry before adding a new layer.

Thinning your oil paint shouldn’t be complicated. It does take some time getting used to how the various mediums work but you can play around with it and learn as you go. Don’t let not knowing hold you back from trying something new. If oil painting scares you, give it a try! You never know what you’ll fall in love with if you never begin.

What are your best oil painting tips?? Be sure to let us know in the comments!