I thought it best to give a general overview of water mixable oils before I go into details of this type of oil paint.
What are Water Mixable Oils (also known as Water Miscible or water soluble)
Water miscible oil paint is a modern variety of oil paint engineered to be thinned and cleaned up with water, thus making it possible to avoid using chemicals such as turpentine, whose fumes may be harmful if inhaled (making it necessary to take precautions, such as using the solvent in a ventilated environment). Water miscible oil paint can be mixed and applied using the same techniques as traditional oil-based paint, but while still wet it can be effectively removed from brushes, palettes, and rags with ordinary soap and water. Its water solubility comes from the use of an oil medium (usually a modified linseed oil) in which one end of the molecule has been altered to bind loosely to water molecules, as in a solution.
Water mixable oils are made using virtually the same pigments as traditional oils, which have a base of Linseed Oil.
Water Mixable Oils also use Linseed Oil, but the Linseed is modified to make it mix with water. This solves one of the most dangerous requirements of Traditional Oils to use Turpentine, mineral spirits, solvents and mediums that are toxic and can cause serious health issues. Most brands of water mixable oils also avoid the traditional toxic heavy metal pigments like Cadmium, however some brands do use these pigments which can emit some toxic elements that are also dangerous to health. However, the biggest gain is the use of water rather than the solvents, which is where the most harm comes from, not the paint. .
First developed in the UK the range of colours has been extended to closely match traditional oils in recent years, and most mediums are rated as non toxic, unlike traditional oils. There are a number of brands on the market, and like their counterpart Traditional Oils can vary between student quality and very high artist quality.
Why use Water Mixable Oils
Many people have allergic reactions to some of the toxic solvents and mediums as well as the strong odours emanating from Traditional Oils, but until recently have not had any alternative except to abandon the Oils and go to Acrylics or Water Colours.
Many state and private schools have had to leave Oil classes alone due to the problem of a large number of people in a classroom all generating the toxic fumes that Traditional Oils and mediums have, as well as the flammable nature of many mediums. They now have a totally safe alternative.
Water Mixable oils are the only alternative that basically is exactly like Traditional Oils to use and manipulate with the same characteristics, archival qualities but can be used without Turpentine, solvents and toxic mediums.
There are a couple of subtle differences, but these are easily catered to. They use the same brushes, same boards and canvas and need no special equipment other than those the traditional oil practitioner would use.
What are the differences compared to traditional oils
The odour of most brand water mixable oils have much lower odour than traditional oils
While water can be used to thin the water mixable oil, they have the same rule of fat over lean that applies to traditional oils. However, water adds no fat, so when mixed with the oil, this is treated as a lean medium, suitable for background washes. If you want to comply with the fat over lean, use the special modified linseed oil available with most brands which gives a very smooth mix, but does add fat to the mix. This difference avoids having two thinning mediums depending on whether a background wash is needed (use water) or thin for fine detail work (use the fat medium/modified linseed oil).
Drying times are usually around 25% faster than traditional oils, 3 – 5 days, thin background washes somewhat quicker.
Cleaning the brushes and work area and even your hands and clothes is a breeze. Just add water. With hogs bristle that tends to absorb colour, a dash of washing up liquid detergent will eliminate any traces of the paint.
Working with Water Mixable Oils
The good news already touched on is that if you can use Traditional Oils then your 98% of the way there with the water mixable oils, but can forget all the cleaning hassles.
The only limitation (which does apply to most traditional oils also) is that over thinning will affect adhesive abilities.
Drying time already faster than traditional oils can be sped up considerably by using the fast drying mediums available for these oils.
Application, colour mixing, special techniques are mostly the same as the traditional oils.
Archival Quality
Most manufacturers of water mixable artist quality oils have done extensive testing and state the archival quality and light fastness ratings are the same as with traditional oils. Despite several brands claiming water mixable oils can be mixed with acrylics, informed views confirm this can affect the archival qualities which have been tested to be exactly the same as traditional oils. Likewise, student quality (hues) do not have the same archival quality, but light fastness is usually quite high and consistent with student quality traditional oils.
Mediums
Water mixable oils usually have a wide range of specific mediums for every purpose, including fast drying, resin gels, thinners, Thickeners, matt and gloss varnish to mention a few.
Mostly, these mediums are non toxic and very familiar to use for experienced artists.
Brushes
The most common brush used with traditional oils is bristle, and the same can be used just as successfully with water mixable oils.
It is a common comment by people who are use to regular oils that they feel the bristle brushes become “soggy.” This can be avoided with water mixable oils by not leaving the brush standing in the water. Dry it immediately and place it on its side to continue drying.
There are many synthetic bristle brushes which are available that work just as well and are a little less expensive than quality bristle, exotic animal hairs or sable.
Many manufacturers make brushes specifically for water mixable oils, but I generally find the only reason they seem better is because the quality is high to justify the extra cost. Traditional Oil brushes of quality can be used quite successfully as long as they are not affected by water.
Summary.
With all State and the federal Governments strengthening laws regarding toxic products, I believe water mixable oils are going to become more accepted due to this. They are just as flexible as any other oil, have the same techniques, archival quality and roughly the same cost, but without the nasty cleaners and mediums that are associated with oils. Regulations for transport of flammable goods is making it almost impossible to ship small quantities of turpentine, mineral spirits, solvents and such like. Even carrying traditional oils onto a plane is mostly prohibited, whereas water mixable oils are not treated that way.
It will also allow schools to re-introduce classes on oils reversing the recent move to Acrylics only.
Give them a try, I guarantee it will clear your head of the fumes if nothing else, and you might be pleasantly surprised at how easy to move away from traditional Oils and avoid the health hazards they represent.
Tips
- Water soluble oil paints are perfect for travel, especially on airplanes. Many airlines restrict traditional and flammable solvents on commercial flights. Eliminating the need for harsh solvents makes water soluble oils easy to pack for painting on location whether by car, plane or horseback.
- The plein air painter can keep paint on the palette for long periods of time without the paint drying out. However, finished paintings dry more quickly than traditional oil paintings which make these new paints even more desirable for the plein air painter.
- Just like traditional Oils, Acrylic gesso can be used as the starting ground for water soluble paints to ensure proper adhesion.
- A few drops of modified linseed oil on the palette restore any paint thinned with water paints to their original workable form.
- All oil paint should be applied fat over lean to prevent cracking.
- Use water to thin the new oils for laying in washes. Build up the oily layers after the under painting is dry. The new oils will remain water soluble after the specific water mixable mediums are used.
- Just like with standard oils, the new paints can be laid down in many smooth thin layers, called indirect painting or can be applied in a thick wet single layer called direct or alla prima painting or everything else in between.
- Do Not mix with traditional oils as the Water Mixable oil will revert back to the Traditional types. However, most brands of water mixable oils can be mixed together safely.
- Use a clear detergent to clean brushes so you can tell when all the colour has been removed, coloured detergent makes this difficult. It only takes a few seconds under a running tap to clean any size brush.
My experience with these oils goes back several years, when Winsor & Newton (The originators of this technology) released the Artisan range. These were in their early form considered a student quality oil, due to the lack of many of the common “better” pigments like Cadmium, Cobalt with these being called “Hue” which has become known as the common signal that it is a student quality paint. . W & N had as a design criteria being totally non-toxic. Over time they reviewed this aim, and introduced better colours to upgrade to a true artist quality paint, albeit retaining the “hue” type pigments so common in student quality oils.
However, over recent years, many manufacturers have improved on the original work of W & N and now there are several variants of water mixable oils, some very good, some no so great. Many have remained non-toxic, not just with the paint, but with the mediums also, something that W & N seemed to have drifted away from somewhat from reviewing their MSDS sheets.

WOil Tube samples
Weber wOils have remained true to the original ideal of non-toxic but are a true artist quality oil. There are currently 32 colours in the range with another 32 Artist Quality colours due later this year.
Next time we will start our review and test results using Weber wOil water mixable oils.
Colin Rayner