Here’s How You REALLY Should Be Thinning Your Acrylic Paint

Michael Daly
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Understand The Construction Of Acrylic Paints From The Ground Up

Acrylic paints are made up of several chemical components, including acrylic resin, solvent and color.

And there are are three main ways to thin acrylic paints.

First, you can thin the paint with a solvent such as methyl ethyl ketone (MEK) or other ketones.

The second way is to dissolve the color in the solvent. And the third way is to dissolve the acrylic resin in acrylic thinner. This step will require higher quantities of thinner and longer mixing times.

The above methods work if you use a number of colors in your paint, but if you combine primary colors (red, blue and yellow), you will create a new color, or tertiary colors. This makes combining colors easier.

When you mix primary or tertiary colors together, you’ll have to reduce the amount of thinner you mix into your paint or otherwise you’ll thin it too much.

It’s recommended that you use acrylic resin solvent when thinning landscapes and large areas because it is so watery.

Methyl ethyl ketone is mild on the skin and works fast for fast business, but acetone can dissolve many plastics, so you have to be careful where you are using it. Some people store and work with their paints outside to avoid the smell of thinner in the house.

Water Is Often The Primary Thinner – Just Take It Easy

You might be surprised at the amount of water necessary to thoroughly thin acrylics. If you find pure water doesn’t give you results that you’re happy with, try experimenting with other solvents like apple cider vinegar, lemon juice or white wine. Any of these will give your paint a little more body and help retain the vibrancy of the color. Apple cider vinegar is perhaps the most versatile, having been suggested to clean your brushes and to extend the life of your box of oil paints.

If you’re still not satisfied, you could always dilute the paint, which might take it too far and give you unsatisfactory results. In addition, diluted paints are harder to retain. However, this might be a necessary step for you if you’re just not getting the results you want. You should also use this method if you’re painting murals or if you’re using a large brush or roller.

It’s important to put safety first when using any solvents to thin your paints. Be sure that you’re using a vapor-safe product so that no fumes become airborne and turn into an irritation or health hazard.

Excellent Mediums You Can Use As An Acrylic Paint Thinner

All acrylic paints have a certain viscosity. Viscosity is the measurement of the thickness of a liquid. A common misconception is that by thinning your acrylics, you will lose the vividness of the color. It is considered that the mere thinning of your paints will allow the color to fade. However, this is totally the opposite of what happens. This is because color is deposited throughout the fibers of the canvas. Therefore, the paints have the ability to use all the space in the fibers. The more space that is available, the more vivid the color.

So, it is risky to use water to thin the paints. This is primarily due to the fact that this water can also ruin your canvas and also lead to warping and swelling. To prevent this from happening, it is highly recommended that you use water-soluble and odorless mediums as paints thinner.

Here are some acrylic paint mediums that you can use as thinners to clean up your brush while drawing, or for transferring your work from one surface to another:

Paper Towels

Still Not Seeing The Results You Want? Why Are You Thinning So Much In the First Place?

Did you know, it’s actually possible to over-thin acrylic paint! (Weird, isn’t it?)

It’s true. Usually when we thin paint, it’s because we want to use it in different ways. For example, we might want to use it in a wet-in-wet way, or a flowing-stroke way. Alternatively, we may be using the paint in a technique that requires a more transparent paint.

We might want to use the paint on finer surfaces or we might want to use it in spatter or dry brush techniques.

If you aim to put down a coat of paint that is different to your normal, thicker, paint application, then you may want to thin the paint.

However, watch how much paint you actually use. If you are still noticing that your paint is a little chalky, try using even less paint for next time. The outcome that you are looking for from thinning paint, is more fluid, translucent, paint with or without a stain. To make the paint this way, you must make sure you are using enough thinner, just enough to make the paint workable. But ensure you are not using too much thinner or you will just end up with watered-down paint.

Working With A Primed Layer Will Help Produce Results

The process of thinning acrylic paint consists of two steps.

The first one is adding solvent to the paint. The second one is mixing the paint with medium. It is important to know and understand these two steps because the outcome of your paint job is very much influenced by them.

It’s essential to use a good quality solvent. You can choose from a wide variety of solvents depending on what you plan to do with the paint. For example, you may choose solvents that are safer for your environment, or you can consider using the ones that are more effective in dissolving the paint.

When thinning your paint, consider the end result that you want to achieve. There’s more than just one common outcome when working with acrylics. The result should be closely related to the type of object you’ll be looking to paint, the personal taste of the artist, and the materials used in creating the object that will be painted.

In order to have the right blend of paint and medium, you must know first the paint’s density. This has to do with how the paint dries. If you’re using solid and opaque paints, the mix should have a higher percentage of paint and a lower percentage of medium.

What Type Of Brush Are You Using For Your Thin Acrylic Layer?

For most acrylic painters, the natural response to thinning paint is to add water. The problem is that your acrylic paint also needs oil to give it gloss and to develop that lovely layer of varnish that is on top of the paint when it’s dry.

There are a few different brushes that you can use to apply the thinned paint. They are made from a range of materials including sable, synthetic, stiff bristle nylon etc. Most of the artists will start everything with a softer brush and then use a stiffer brush for the last layers as it’ll help you get into sharp corners.

However, watch out for those stiff brushes if you’re using a dark paint on a light background. Some stiffer brushes may catch on the light background and leave a few thick lines behind that won’t soften up even if you add more thinner. When that happens, the only way to soften those lines is to add more paint to cover them up.

Never Forget Fat Over Lean When Using Thinner Acrylic Paint

For years I’ve heard the phrase “fat over lean” when referring to thinning acrylic paint. Though the phrase has seemed to make sense, I’ve never really stopped to think much into it.

Whenever I was painting, I’d usually just add the paint until it looked good. Then I’d add a couple more drops for good measure.

I had no idea there was a correct way how to thin my acrylic paint.

Then a couple of years later I started seeing tutorials on YouTube about how to thin your acrylic paint.

I learned that there was much more to thinning your acrylic paint than just adding some water or water-based medium to it.

This Isn’t All The Methods To Thin Acrylic Paint

[Every other article I read that shows you how to thin acrylics paints, says pretty much the same thing…

Pour in a little bit of solvent. Stir for a few seconds with a palette knife.

Drag a wash or a glaze across the palette.

And ta da! They’re ready to use.

The problem I see with this article, is that it doesn’t really describe to you how different brands of solvent, or which brand to choose, and how to mix the solvent properly in a way that makes for perfect, clear, and truly thinned paints.

You can’t just pour Solvent in and stir it up, then expect good results.

That’s the easy part.

What’s NOT easy, is getting the right consistency, especially if you are a beginner. And when I say the right consistency, I mean the consistency where it’s thin enough to wash across the surface, but thick enough to cover up a drawing or a painting underneath.

And after you thin your paints, how long will it take for the solvent to evaporate?

Won’t the solvent interfere with the binding agents of the paint?

Will the paints stay thinned for long enough?

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