Making Handmade Oil Paint
You can make good oil paint with just pigment, a drying oil and a palette knife. But most artists making there own paint take it a step further and take the paste created with the palette knife and grind it with a muller on a slab to produce smoother paint that keeps better without separating and may have better handling properties when painting. Some artists take it even a step further and learn about the chemistry of each pigment and each oil and find out about additives that improve the paint just that extra bit. It’s up to you, but it’s easy to get started by making a simple oil paint using just two ingredients and a tool you probably already have.
There are a few reasons that artists make their own oil paint. Some artists enjoy the satisfaction of making paint from scratch and then making a painting with their own paint. When you make it yourself you can customise the colours and textures. If you find an inexpensive source of pigment, you might even be able to save money making it yourself. You might find an unusual pigment like the Jackson’s Van Dyck Brown Natural NBr8, a complex, transparent, grey brown, natural earth that from many sources is not always reliably lightfast, but ours is lightfast. So you might want to make your own Van Dyck Brown paint to ensure that you are using this pigment. (Also spelled Van Dyke Brown.) Potters Pink PR233 is another example of a pigment you can’t normally get in oil paint, but could make yourself. Some artists even gather their own pigments from nature to make paints. Some artists make their own paint because they like to know what is in their tube of paint. Unlike food or cosmetics, artist materials do not require a list of ingredients and the list that is voluntarily put on some materials is often only a highlight of the main ingredients, but doesn’t list everything.
Another reason to make your own oil paint is that you are able to bring out the full potential of each pigment. As with all commercially made products, things are added for the convenience of manufacturing, or storage, or shipping that might not be the best choice for the product but rather are a compromise to make production easier. When you make paint yourself you don’t have to compromise. You will discover that some pigments don’t want to easily mix with the oil, so you might try a different oil like we will do with the Ultramarine Blue paint, using poppy oil. You might find that some colours take longer to grind into the oil. Some require twice as much oil as others. Some are very fine and smooth but some have a faintly gritty texture that makes them almost sparkle. Some will be best as a thick paint and some will be better as soft, runnier paint, some will dry fast and some will dry slowly. By practice you will get to know your pigments and with some research and experimentation you will be able to make paints that show each pigment at its best.
Making your own paint can be a meditative process that makes you feel a closer connection to your materials and to the history of painting. The process is simple but it does take time if you are going to grind the paint. You first mix dry pigment with a drying oil into a paste, then you rub a hand-held glass muller over the paste on an etched glass slab to ‘grind’ the paint, which means to coat every particle of pigment with the oil. It can take a few minutes to grind a teaspoon of paint but 30 minutes to 2 hours to make a tube of paint. Each pigment will be different. Once you start grinding you might want to time the process, so you will know for next time how long that particular colour, made with that particular source of pigment, took to make.
Factory-made oil paint is put through a triple roll mill that does the same thing that grinding by hand with a muller does, but makes larger amounts, much faster. Commercially made paint usually has added stabilisers to keep the pigment from separating, which creates a ‘short’ and buttery paint where all the colours have the same body. Most, like alumina stearate, do not cause any problems for longevity, but some, like magnesium carbonate, have been found to change over time so that an oil paint film can become sensitive to water. Having the stabilisers in the mix slightly reduces the ratio of pigment to the rest of the paint, slightly changing the critical pigment volume concentration (CPVP). CPVC is the pigment concentration where the pigments are packed as close as possible and the binder is exactly the amount required to fill the space between the pigments. But you may wish to add some additives to your paint. You might want to add calcium carbonate (whiting) to a titanium white to help it dry faster and help it approximate some of the transparency of a zinc white a little bit. A small amount of warm wax (less than 2%) might be added to some paints like Ultramarine Blue that resist wetting, to help them mix into the oil. There is a huge amount to learn about additives for oil paint, which I won’t be covering in this article. I am going to look at the fundamental ideas and ways to get started.
How to Make Oil Paint by Hand – an Introduction
To make oil paint by hand you first mix dry pigment with a drying oil into a paste, then you rub a hand-held glass muller over the paste on an etched glass slab to coat every particle of pigment with the oil. With the mulling process you are not milling the pigment, which is grinding the pigment into a finer powder. It already comes as a fine powder of the appropriate particle size. With mulling you are combining the oil and powder until every particle of pigment is fully encapsulated. Most of the time (and expense) of making any oil paint lies in the meticulous care taken in coating each particle of pigment with the drying oil.
It is possible to make paint with just a palette knife, but it can take a while to get the paint smooth and to coat all the pigment with oil, and you usually have to use the paint the same day or it will separate. If you want to make a batch of paint and store it in tubes, then grinding with a muller is recommended. It combines the pigment and oil better so there is less chance of them separating in the tube. You can use a muller on a smooth glass slab, but it takes much longer than mulling on a frosted glass slab, which is much faster at making the paint smooth. Read our earlier article about Making a Grinding Slab inexpensively, in less than an hour.
As artists painting with oil paint, we get to know the paint intimately on the level of colour mixing, texture, and differing levels of stiffness between brands, the drying time differences between colours and brands, and the characteristics of each colour such as transparency or opacity, colour bias, and lightfastness. Some painters make colour charts or colour wheels and take notes during painting, to try to systematise their understanding of their materials.
But if you wish to make your own paint, you could look at oil paint on a deeper level, you may want to understand the basic chemistry of the ingredients so that you can get them to combine to make a paint that you like. Knowing the properties of each pigment, and of the variety of oils and of any other ingredients you add, will allow you to make a paint that has the characteristics you want.
But I know a number of painters who make their own paint each time they paint, without much fuss. They combine oils and pigments into a paste that they can paint with, without getting deeply into the chemistry at all. And they do all their mixing with just a palette knife. So you can approach it how you like.
For this article I have chosen to make two simple paints, just oil and pigment ground together. I have chosen Van Dyck Brown because it’s a lovely colour and our Jackson’s pigment is unusual because it is a natural, lightfast source. So I wanted to take the opportunity to have a lightfast version of this lovely, transparent grey brown oil paint. In the next instalment of this article, I will be making Ultramarine Blue, because it is a notoriously difficult paint to grind into oil, so I will try grinding it with poppy oil. Here, I also show some images of an Ultramarine Blue that I made with linseed oil a few weeks ago (without any difficulties).
Choosing Your Oil
The drying oil binder is usually linseed or walnut oil or in the case of whites and pale blues, safflower or poppy oil. The oil holds the pigments together as a paint film, so it is important to have enough oil to form a strong film. But oil is a slow-drying binder because it hardens by oxidation (absorbing oxygen from the air) and not by evaporation. Having too much oil will mean that the paint can take years to become even touch-dry. You also want paint that is thick enough to pick up with a paintbrush and an excess of oil will make it runny. Also, having as much pigment as the oil will hold, means that the paint will yellow less as it ages, because the oil is the part that yellows, and a good pigment load can cover over that yellowing. Linseed oil is the most popular oil to use because it is the strongest of the oils but the chemical bonds that make it such a good binder also make it yellow over time. But, again, a good pigment load will mask any yellowing of the oil in all but the white colours. Cold-pressed linseed oil is the type of linseed oil most used for paint making because it has the thinnest body so it more easily surrounds each pigment particle.
You can read more about the drying oils in my earlier article Watching Paint Dry: Drying Oils.
Pigment is the coloured part of any paint. (Note: these terms for pigment are usually used interchangeably: raw pigment, dry pigment, powdered pigment, ground pigment.) The powders are produced from heated metals, or ground rocks, or complex laboratory procedures that start with turpentine or naphtha. For instance, Ultramarine Blue is a pigment that at one time was made from Lapis Lazuli rocks dug from the earth in Turkey. They ground those blue semi-precious gemstone rocks up and sold the powder to paint makers who mixed it with linseed oil to make blue oil paint. It was very expensive blue paint so was only used for the robe of the Madonna in Renaissance paintings. Many years later they found a way to heat certain metals and combine them with other chemicals and make a very similar blue in the laboratory. That blue powder was much cheaper. But it, too, is a powder of fine particles that you can mix with linseed oil to make Ultramarine Blue oil paint, so now that colour of paint is much more affordable.
Pigment must be mixed with a binder to make it into a paint – oil, gum, emulsion, egg yolk, polymer, glue, etc. One way to think of binders is as different types of glue – the binder glues the pigment to the surface. To make watercolour paint you mix the pigment with gum arabic. To make acrylic paint you mix the pigment with acrylic polymer. To make household paint you mix the pigment with a latex emulsion. Painters that use Egg Tempera paints make their paints fresh each day with dry pigments and egg yolk. If you were to add water to just dry pigment and paint it onto a surface, when the water dried the powder would all brush off and blow away. There are powdered paints that look similar to pigment, but they have a powdered glue in them that when wetted becomes a paint and will stick.
Even thought most artists don’t make their own paints, they do want to know which pigments are in the paints they are buying. Because Winsor & Newton call their oil paint that is made with PB:15 Phthalocyanin Blue, Winsor Blue, and Schmincke Horadam watercolour using the same pigment calls it Sapphire, and Golden uses the same pigment in an acrylic paint that they call Manganese Blue Hue – it helps to know that since the label says they all contain PB:15 – then the painter knows that they are all Phthalo Blue paint.
There aren’t that many pigments available to make paints. The reason there are many colours in some ranges of paints is because they mix pigments together in different ways, so many paints are mixes of pigments. And knowing which pigments are in your tube, will help you predict how the colour will mix with other colours. So some artists prefer to use single pigment colours because mixing is far more predictable.
The pigment is the expensive part of any paint. That is why paints are priced in a series. The paints containing the more expensive pigments are priced higher than the paints containing less expensive pigments, even though they have the same binder in them.
Every pigment is a different chemical and when combined with a drying oil it absorbs a different amount of oil, this amount varies greatly. In addition, each oil is a different combination of fatty acids so using the same pigment but with a different oil can change the characteristics of the paint, making a difference to how long and stringy or short and soft it is or if you can get a thick paint or if it becomes more liquid over time, or if it the oil and pigment separate in the tube. Each pigment is ground to a size that shows it at its best, so they are all ground to slightly different particle sizes. And some are ground to a selection of different sizes to change the transparency or shade and get a few different colours from one pigment.
Pigment is composed of tiny powder particles that cluster together into very small soft clumps. The reason for grinding pigment into the binder (also called vehicle), which for oil paint is a drying oil and for watercolour paint is gum arabic, is to shear these tiny clumps into individual particles. The pigment is not being milled into smaller pieces, and it doesn’t take any force to grind up the pigment, you are just gently breaking their urge to stick together, so that each individual particle is enveloped in oil and all the air between particles has been pushed out and replaced with oil. Pockets of air disrupt both the opacity of opaque colours and the transparency of transparent colours. For most pigments, it just takes gentle circles of the muller. Some pigments however, resist being incorporated with the oil, they are strongly attracted to each other and want to stay clumped up, these are said to be “hard to wet”. You don’t need to use more force with the muller, that won’t help, for these you might want to use additives or to use a different oil. I have made Ultramarine Blue with linseed oil and had no problems. But it has a reputation for not wetting well with oil, so it takes extra oil to make the paint and then it is too runny. Commercial paint manufacturers either add alumina stearate to form a soap that helps the pigment be wetted by the oil or a tiny amount of warm wax. Another option is to use poppy oil which reputedly wets this pigment better. But the downside is that paints made with poppy oil take longer to dry and don’t form as strong of a paint film when dried, though they won’t turn yellow over time. I chose to use poppy oil to make the Ultramarine Blue that will be in Part 2 of this article.
Jackson’s now stock 100 pigments in small or large jars. They are easy to open and close so there is less chance of pigment being blown around. Be aware that pigments are sold by weight, not volume. Since we only use two sizes of jars, a jar may be only a little full, half full or very full. But the weight of the pigment you have purchased will be correct.
Read more about pigment in our Pigment Series.
Making Oil Paint by Hand
It helps to lay a damp rag, paper towel, or tea towel flat underneath the mulling slab, like chefs put under their chopping boards, to prevent the slab moving on the table while you are grinding your paint.
Begin with a small pile of pigment on the slab. Make a well in the centre to pour in a puddle of oil, visually I start with about equal parts oil and pigment. Stir and scrape with a palette knife until it is a stiff but workable paste, incrementally adding more drops of oil or a little more pigment until you reach the right texture of paste. A pipette is useful for the controlled addition of drops of oil near the end because the change from too dry to too wet is sudden. The mixture will become more runny as you grind it, so it’s good to start with a pretty stiff mixture, stiffer than toothpaste.
Test for the right proportion of oil to pigment by doing the peak test. Lay your palette knife flat on the paint pile and lift up. The peak left on your paint palette should stick up. If it falls over too much your paint has too much oil. If it breaks before it can form any peaks it needs more oil. The Van Dyck Brown and linseed oil mixture was the right viscosity, so I started mulling. As I ground it, it got first stiffer and then after a while softer.
You can also judge if you have the right amount of oil pretty reliably by the sheen of the paint. If it is glossy it is too oily, if it is matt it is too dry, if it is satin it has the right amount of oil to pigment. A third test is about how it feels as you are grinding the paint – does the muller skip over the paint (too dry) or is it sticky and the muller suctions to the slab (the right consistency)?
If you are making paint to use the same day you don’t always need to mull it, just continue mixing it with the palette knife until it is smooth. And then you are ready to paint!
Grinding the Paint
If you are going to grind the paint, then place the muller on top of the paste and begin mulling. Move the muller in a large circle, changing direction, switch to a figure eight, make little circles, trying to cover all the paste. Do not put any pressure on the muller. Scrape the sides of the muller regularly with a palette knife or by tilting the muller and twirling the side into the paint pile, to incorporate that drier paste back into the mixture. After a few minutes, scrape the spread out paint into a pile in the centre of the slab. If the paint is too runny that means there is more oil that is ideal so you can sprinkle pigment on the smooth mixture and fold it into the mixture with your palette knife – if you put your muller on top of the powder it can slow down the mixing, if the powder sticks to the muller. You will then need to mull for a few minutes to ensure the new particles are fully coated with the binder. If the muller suctions to the slab, you may need to pry it up with the palette knife.
I tested using a variety of tools for the most efficient way to scrape the spread out paint back into a pile in the centre. I used two different silicone tools, an old credit card, a decorator’s paint scraper, a small squeegee, and the palette knife I originally used to mix the pigment and oil. I found that there wasn’t much reason to get out another tool, the palette knife worked as well or better than all the others.
Mix a little at a time and incorporate that into the rest, then do more and incorporate it, until you have a large enough amount for a tube. Or do a large pile all at once and after it spreads out into a large thin layer, scrape it all up into the centre again. Grind with the muller until it looks smooth and feels ‘long’. It can take a few minutes per spoonful of paint. You know the paint has been sufficiently mulled and is done when it is very smooth. Test for the right proportion of oil to pigment in your finished paint by doing the peak test again.
Get Into a Rhythm
I am right handed, and this is how I do it.
- Standing, hold the slab down by resting your weight on your left hand on a clean area on the left side of the slab (the damp towel underneath helps, but is not quite enough to prevent sliding around a bit).
- Move the muller in circles with your right hand.
- When the paint pile has formed a large circle and gets a ridge of paint built up around the edge and the muller starts to skip because there isn’t much paint under it, then lift the muller. It might suction to the slab so only lift it up a couple of cm, wait a moment and catch the slab with your left hand as it falls.
- Transfer the muller to your left hand so you can pick up the palette knife.
- Scrape the muller with the palette knife, scrape the ring of built up paint into the centre, wipe the palette knife off on the bottom of the muller.
- Put the muller on the paint pile and put down the palette knife and begin grinding again.
You get into a rhythm of stopping, switching hands and starting again.
Putting Your Finished Paint into Tubes
To store your paint you will need to put it in a container with no air gap in it, like an empty paint tube. Scrape the paint up with your palette knife and scrape it into the open end of the tube. Tap the lid of the filled paint tube very gently a few times on the table to get the paint to settle to the cap end, the tube is soft and can be damaged so do it lightly. Pinch the tube-end up to the bottom of the paint. Fold over the edge against a palette knife 3 or more times. To see more on filling oil paint tubes, see our earlier article Filling Your Own Oil Paint Tubes.
You can label with anything but you can make a nice hand-painted label with a strip of gessoed canvas. If you stretch your own canvas it’s a way to use up any primed canvas scraps. A piece about 10.5 x 2.5 cm works well for our 60 ml empty tubes. Glue the strip on with overlapped ends, around the top edge of the tube. I use PVA, but other glues will work. Leaving room in the top half of your label for the paint strip, you can write the paint info on using a Sharpie Permanent Marker, as some other fine liners will smear with solvent. I include pigment name and number and source, the oil, the amount of time it was ground and ratio of pigment to oil, and the date. Then paint a swatch around the top, using the paint left on the slab. Painting a thick layer and next to that a thin layer may show your colour better. You may want to change your gloves before starting or you may end up with paint all over everything you touch.
Be sure to clean your muller, slab, and palette knife right away with solvent and then soap to prevent any oil paint drying on the slab and thereby filling in and smoothing out your etched surface or having colour left on it to contaminate your next colour of paint.
Making Ultramarine Blue with Linseed Oil
These are images from making Ultramarine Blue oil paint with linseed oil a few weeks earlier.
Although I didn’t have any trouble getting the Ultramarine Blue (red shade) to mix with the linseed oil, I will be making the same blue paint but with poppy oil next week, to see if that is indeed better.
The Body of Handmade Paint
Hand grinding oil paint usually produces a softer paint than you get in a commercially made tube because it is too hard to use a muller on super stiff paint. But you can make a stiffer paint if you work it with a palette knife only.
To make the Van Dyck Brown took 45 g pigment to 40 g cold-pressed linseed oil. Van Dyck Brown is also called Kassel Earth and it is generally manufactured with about 70 parts oil to 100 parts pigment. To get mine to grind by hand I had to use about 90 parts oil to 100 parts pigment. Although I could have kept adding more pigment because the paint softened as it was ground, I could probably only get it down to 80 or 85:100. So it would still be a bit oilier and softer than paint put through a triple roll mill.
How Much Oil Paint Does Each Pigment Make?
Since the volume of paint created will be a combination of the amount of pigment and the amount of oil, it depends greatly on the oil absorption rate of the pigment. For the Van Dyck Brown that I made – about half the 100g pot of pigment and half the 100 ml bottle of linseed oil made about 3/4 of a 60 ml tube. In the photos of the tube folding it looks just over half full, but I set aside a couple of spoonfuls in a couple of jars to test for separation over time and to test painting with, and I lost some from wiping off the palette knife for different photos. I have never measured our 60 ml empty tubes to see how much folding you can do before it has less than 60 ml contents. I like at least three folds at the end of the tube, so a 100g pot of Van Dyck Brown pigment and a 100 ml bottle of cold-pressed linseed oil would make one and a half to two 60 ml tubes of paint.
Paint Making Safety
When making oil paint, you want the opposite of ventilation, you want still air. There are no fumes to worry about removing and you don’t want the dry pigment powder to get into the air for you to breathe. Even for the more harmless pigments like the earth colours, you should always wear a dust mask because when you are working with anything dusty, the pigment particles are so fine you can’t really see them in the air, but you will be breathing them in. Wearing protective gloves like our nitrile gloves is a good safety precaution, to prevent any of the more toxic pigments from absorbing into your skin and to prevent pigment getting under your nails. Avoid eating and drinking around dry pigment. Since you are working with a fine, dusty particulate, make sure there is no food or drink in the room that the fine powder could settle on. Consider wearing eye protection. Keep out of reach of children and pets.
Always read the label and re-label pigments you’ve put into a new container. Jackson’s pigments come in sealed, easy-to-open containers, which means less blowing around of pigments, than the ones that come in bags. Clean all surfaces well with a wet cloth to pick up any dusty materials.
Oil Absorption Rate of Pigments
When making oil paint, there is an optimal ratio of pigment to binder for each pigment. Excess oil will make the paint soft and if the oil is linseed oil, excess oil will cause the paint to turn dark yellow over time. Some art materials books give charts of the oil absorption of different pigments, but because each pigment can be ground differently and be from a different source, these charts give wide ranges that means they are not very useful. If you want a chart, it is best to make your own chart using the specific pigment you are using. Doing it by weight is most accurate so if you are measuring, then you will need a scale. Weigh your palette and then add 100g of pigment, then add your oil very slowly, working it with a palette knife until it forms a stiff but workable paste. The weight of oil you use for 100g of each of your specific pigments, will be the general oil absorption level, which can be used as a starting point each time when making your own paints. Then you can make slight adjustments by adding a drop more of oil or a bit more pigment if needed. But you don’t really need a chart because you will be making it by feel anyway, the right ratio is when you get a stiff but workable paste.
- Glass Mullers
- Glass Palette
- Palette Knives
- Calcium carbonate
- Empty Paint Tubes
- Drying Oils
- Dust Mask
- Nitrile Gloves
- Eye Protectors