Water mixable oils are a unique painting medium. You can use them like regular oils but you don’t need solvents. They’re basically regular oils that you can clean up with water.
They’ve only been around since the 1990s so they’re not as widely used as traditional oils.
Naturally, if you’re thinking about switching to water mixable oils from another medium, you’re going to have questions.
One of the most common questions is about the drying times. Below, I answer the questions and provide information from the manufacturers. I also link to the pages on their sites where they discuss drying times.
In this post, I cover how long it takes for water mixable oils to dry, and how to make them dry faster or slower.
I think people believe that they contain water and that they’ll dry fast like acrylics. This is not the case.
Water mixable oils don’t contain water at all. They’re the same as regular oils, but they add an emulsifier to the paint so that you can mix it with water.
I spent a lot of time researching this information for myself and thought I would compile it here so that others could save some time.
It’s important to note that “touch dry” is not the same thing as a paint layer that’s cured and ready for varnishing. It can actually take a year or more for thick oil paint to dry thoroughly. In this article, I’m mostly referring to how long it takes for an oil painting to dry to the touch.
Also, I didn’t encounter any information about what qualifies as impasto. I would think that subtle brush textures would dry within a reasonable amount of time.
However, very thick layers of oil paint take a long time to dry. There are issues with using oil paint too thickly, but that’s a topic for another post.
How Long Does It Take for Water Mixable Oils to Dry?
Water mixable oils take on average anywhere from 2-5 days to dry to the touch. The drying times vary depending upon the thickness of the paint, the types of mediums you add to it, and the pigments that it contains.
Thicker layers of oil paint can take weeks or even months to dry. As I stated above, even though a thick layer is dry to the touch, it takes longer for the oil paint to fully harden.
The drying times vary a little between brands so I add those details below if you’re interested in a particular brand. This is information that comes direct from the manufacturers so it should be accurate.
Not all of the major brands include information about the drying times.
On the Grumbacher website, they state that their max water mixable oils dry at a rate that’s comparable to regular oils.
Holbein doesn’t mention the drying times so I would assume it’s similar to other water mixable oils. Daniel Smith doesn’t state anything about drying times on their site.
How Long Does It Take for Cobra Water Mixable Oils to Dry?
According to the manufacturer, thin layers take 2 to 7 days for the paint to dry to the touch. It depends upon the temperature, light, and the colors you use. It can take up to 1 month for thicker layers to dry.
This is based upon the information on page 73 of their revolution magazine. It contains information about Cobra paints and interviews with artists who use them.
They say that Cobra oil paints have all of the characteristics of traditional oils, including the drying times.
You can use them for painting alla prima, wet into wet, impasto, glazing and more.
I found that my tests with student cobra water mixable oils dried to the touch in about 4 days. This was a quick test where I applied a thin layer of various colors to an inexpensive canvas board.
Water mixable oils clean up with soap and water. You can also use water to thin the paint out for the first layer of the painting. No solvents are required!
How Long Does It Take for Artisan Water Mixable Oils to Dry?
The Winsor & Newton website says that it takes about 2 to 5 days for them to dry to the touch. A few of the colors can take more than 5 days.
One the the things about painting with oils is that some of the pigments dry slower than others.
Winsor & Newton lists the drying times of different pigments on their site, below is a quick summary of how the pigments vary in drying times.
Slow Drying Pigments
The slow drying pigments can take more than 5 days to dry. These are the Cadmiums, Permanent Rose, and Permanent Alizarin Crimson.
Medium Drying Pigments
Medium drying colors are the Cadmium Hues, Phthalo Blue, Phthalo Green, Siennas, French Ultramarine, Ochres, Titanium White, Zinc White, Lamp Black, and Ivory Black. These take about 5 days to dry.
Fast Drying Pigments
Fast drying pigments can dry in as little as 2 days. Prussian Blue and the Umbers are the only pigments they claim are fast drying in this line.
Here’s a link to the drying times of Winsor & Newton oil paints on their website. It includes information for the Artisan water mixable oils.
Why Does the Pigment Color Affect the Drying Times of Oil Paints?
The pigment affects the drying times of oil paint for two reasons. Some pigments require more or less oil in order to achieve a consistency that’s suitable for painting. These variations in oil content affects the drying times of each color. The second reason is that the pigments, and even impurities they contain, can accelerate or retard drying times.
I’ve heard both of these explanations from various artists over the years. However, I was looking for a more authoritative source. This article from Golden explains how pigments affect the drying times of oils in detail.
From what I understand, some the pigments are made from materials that affect how much oxygen the paint can absorb. Oil paint requires oxygen to harden, so this affects the drying times.
Read the Golden article for a more thorough explanation, see the paragraph titled “Pigment.”
Don’t worry if this is too technical. You don’t really need to know all of this to paint successfully with oils. You just need to know HOW to control the drying times. I discuss how to do this later in the post.
How Long Does It Take for Lucas Berlin Water Mixable Oils to Dry?
Lucas says the surface drying time for all colors it between 5 to 7 days. Thick impasto layers can take up to a year to dry.
The Lucas website doesn’t have a lot of technical data on it other than the basic information.
They claim on their site that the Lucas Berlin paints (link leads to Lukas website) can be used for all of the traditional oil painting techniques. And that there’s no difference to regular oils.
How to Make Water Mixable Oils Dry Faster?
Many of the manufacturers offer a fast dry medium that you can add to water mixable oils. Oil paintings will dry faster when exposed to light that contains UV, in a room with good air circulation, and low humidity.
Below is a sampling of the different fast dry painting mediums that you can use with water mixable oils.
I recommend using the medium from the manufacturer of the paints that you’re using.
As I explained earlier, oil paint requires light and oxygen to dry. This means that you want to leave your painting to dry in an area where there’s light.
Winsor & Newton says their Artisan fast dry medium will reduce the drying times of their water mixable oils by 50%. Since they state that their colors will dry within 2-5 days, then you can assume the fast dry medium will make them dry within a day or two.
Some people say the fast dry mediums may have a little bit of a chemical smell to them. So read the reviews before you buy them.
Oil Paint Requires UV Light for It Dry
It’s the UV component of light that helps to dry oil paint, so daylight may work better than in artificial light.
Here’s a list of light sources that DON’T produce UV. LED bulbs are becoming more popular because they’re efficient and the prices have become affordable. But they produce little or no UV light.
So putting your oil painting beneath an LED bulb is not going to help it dry any faster.
Here is some real world data from Golden about how light sources affect the drying times of oil paints. The results vary. Some colors dry faster when exposed to light, while others were largely unaffected.
They found that even subdued lighting could make the paint dry slower.
Can You Use a Hair Dryer to Make Water Mixable Oils Dry Faster?
A hair dryer has little effect an how long it takes for oil paint to dry. Oil paint hardens through oxidation and not through evaporation so the blow dryer won’t have much of an effect.
I think this idea comes from the fact that heat and air flow will make water based painting mediums dry faster.
For example, if you use a hair dryer on acrylics or watercolor paint, it will dry in a matter of minutes.
This doesn’t work with oils. It doesn’t matter if they’re traditional or water mixable oils, a hair dryer doesn’t do much to make the oil paint dry faster.
That’s because water based painting mediums dry through the evaporation of water. Once the water evaporates it begins to dry.
For an in-depth technical explanation on how oil paint dries, read the article from Golden that I linked to in the section about how pigments affect drying times.
A simple explanation coming from an artist without a degree in chemistry, oil paint hardens through a chemical reaction. The molecules link together and this is what causes the paint to harden.
The FAQs on the Royal Talens site also state that oil paint requires UV light along with oxygen for this process to happen.
Warmer temperatures will have some effect on dying times but it’s not as if you’ll be able to completely dry an oil painting in a few minutes with a hair dryer.
I haven’t tested this myself but I would assume that if you thin the water mixable oils with water, the hair dryer may drive the water off faster. However, what remains is a layer of oil paint that dries as slow as regular oil paint.
How to Make Water Mixable Oils Dry Slower?
You can add water mixable linseed oil or other slow drying painting mediums to water mixable oils to make them dry slower. The fat over lean principle still applies so you want each successive layer to dry slower than the last.
Another thing to consider is the pigments have an affect on the drying times.
Some of the brands say they have uniform drying times. Daniel Smith states that their water mixable oil paints have uniform drying times.
However, the Winsor & Newton water mixable oils have different drying times.
A palette made up of the slow drying colors would give you more time to blend the colors.
Add this linseed oil to your water mixable oils to improve flow, increase gloss, and slow the drying times. Best of all you can clean it from your brushes with soap and water!
I find that all of the water mixable oils have enough working time, although I’m used to the very fast drying times of acrylics though.
I would start out by adding a very small amount of linseed oil to your paints and go from there. Adding too much medium can also make the paint more transparent.
Almost all brands of water mixable oils will dry within 2 to 5 days. But there are many variables that will increase or decrease the time it takes for your painting to dry.
I think it’s the thickness of the paint application that has the largest affect on how long it will take to dry. Really thick impasto applications will take a long time to dry. You should look into a medium that is made for this purpose.
For example, the Winsor & Newton artisan impasto medium will make the paint thicker. It also contains dryers to make the paint dry faster.
If you want your oil painting to dry faster then you should store it in a location that has a decent amount of light. Storing the painting in a drying rack or an area that’s dark may increase the time it takes for it to dry.