Drying oils can be mixed with solvents to make your medium more lean in the beginning stages of your painting process. As you continue painting, you’ll reduce the amount of solvent and increase the amount of oil to produce more “fatty” layers.
Each type of oil has a different property—read below to learn some of the differences and to determine which will be best for the effect you’d like to achieve.
Drying Oil: Oils like linseed, poppy, and walnut that have the chemical properties of creating a solid, elastic surface when exposed to air (oxidization). Non-drying oils that are unsuitable for oil painting are olive oil and almond oil.
Linseed Oil: This is a very basic drying oil. It’s the binder for most of the paints you buy. There are a lot of different kinds of linseed oil…
Black Oil: Linseed oil that has been heated with lead. Very popular with the old masters, but the addition of lead makes it toxic. Not recommended.
Cold Pressed Linseed Oil: The purest of all the linseed oils, cold pressed linseed oil is extracted without the use of heat and dries slightly faster than refined linseed oil. Improves flow of paint and increases gloss and transparency.
Drying Linseed Oil: Darker than refined linseed oil, it promotes the fastest drying rate of all the linseed oils while increasing gloss. Improves flow, increases gloss and transparency. Can be mixed with other oils to speed drying.
Refined Linseed Oil: Low viscosity oil that dries slowly. Increases gloss and transparency. Can be mixed with other oils to slow drying.
Stand Oil: Pale, thick oil that slows drying time and gives a smooth, enamel- like finish with no brush marks. Increases film durability. Good for glazing when mixed with a little solvent.
Sun Thickened Linseed Oil: It’s basically regular linseed oil that’s been left in the sun until it’s the consistency of molasses. Usually mixed with other mediums and not used just on its own.
Poppy Oil: Slow drying oil that’s good for wet-into-wet techniques. It’s the palest oil making it good for light and white colors. Resists yellowing, increases gloss and transparency.
Drying Poppy Oil: Same as regular poppy oil, but with an added siccative (drier) that makes it dry more quickly.
Safflower Oil: Slow drying oil that’s good for use with pale colors. Increases gloss and transparency. Resists yellowing.
Maroger: (say, “MARE-ah-zhey”) Also called Flemish Maroger. This is a mix of black oil and mastic varnish. Black oil is made by heating linseed oil with lead, making this a toxic medium that’s also likely to darken your paints over time. You can get this same effect with Gamblin’s Neo Megilp, which is non-toxic and won’t darken paints.
Alkyd mediums are synthetic resin-based mediums that offer the same effects as old Master recipes, but are specifically formulated to be non-toxic. They tend to quicken the drying time of oil paints, but not to the extent of acrylic dry time. Alkyd mediums are especially helpful for those working in built-up layers of glazes as they generally dry within 24 hours, making it possible to add new glaze layers daily.
There are many different kinds of alkyd mediums available on the market. Here are just a few of the most popular:
Galkyd: Galkyd thins oil colors and increases transparency and gloss. When used in greater proportions with oil color, Galkyd will level brushstrokes, creating an enamel-like surface. Fast drying—thin layers will be dry in about 24 hours.
Galkyd Lite: Thins oil colors and increases transparency and gloss. Will retain brushstrokes when used in moderation. More fluid and less glossy than regular Galkyd.
Galkyd Slow Dry: Increases transparency and gloss, more fluid and less glossy than Galkyd Lite.
Neo Megilp: Soft gel medium that maintains the body of oil colors, increases transparency and flow, and imparts a smooth, silky feel. Dries to satin gloss. Use in place of Flemish Maroger.
Galkyd Gel: A stiffer gel than Neo Meglip, it holds thicker, sharper brushmarks and dries relatively quickly. Galkyd Gel increases transparency of oil colors and creates impasto.
Walnut Alkyd Oil: Non-toxic and solvent free medium that speeds up drying time without yellowing colors. Use sparingly and read the instructions for use. If you use too much, walnut alkyd oil tends to bead up.
Alkyd Glazing Medium (Utrecht): Alkyd-based medium that thins oil paints and speeds up drying time. Good for painters that work in thin glazes since it dries usually overnight.
Liquin: Same as alkyd glazing medium, but produced by Winsor & Newton. There are several kinds of Liquin: Liquin Original, Liquin Fine Detail (glossy, leaves no brush marks), Liquin Impasto (retains texture and brush strokes), Liquin Light Gel (gel that thins out as you brush it, good for glazing), and Liquin Oleopasto (semi-matte, quick drying, good for texture work).
Cold Wax Medium: Made from beeswax, it makes colors thicker and more matte. Read the instructions on the label. You only need a small amount of cold wax medium in order to make your paint more matte (not shiny). Too much and it will crack off your canvas. Can also be used as a matte varnish on a fully dry painting.
Driers can be added to oil paints to speed up drying time, but exercise caution when using them: adding too much can cause paint to crack.
Cobalt Drier: Another drier that speeds up the drying time of paints. Cobalt drier is safer for your painting than other driers, but because it’s so strong you should only add it in small drops at a time and never directly to paint. Mix it with another medium first then add that to your paint.
Ralph Meyer suggests some different oil painting medium recipes in his book The Artists Handbook of Materials and Techniques (which I highly recommend) [link to: http://www.amazon.com/The-Artists-Handbook-Materials-Techniques/dp/0670837016/ref=sr_1_1?ie=UTF8&qid=1407169409&sr=8-1&keywords=ralph+mayer]. One medium recipe that includes cobalt drier goes like this:
1 ounce stand oil
1 ounce Dammar varnish
5 ounces turpentine
15 drops Cobalt drier
The Cobalt drier is added to accelerate the drying time of the slow drying stand oil, but if too much is added, the medium will coagulate. Ideally, a glaze should dry rapidly so artists can proceed with layering subsequent transparencies. The best glazes will dry overnight.
Japan Drier: Alkyd resin-based liquid drier. Not recommended for use in fine art oil painting since it has a tendency to darken and yellow paints over time. Good for gold leaf if you let it dry till it’s tacky then apply gold or silver leaf, smooth, and burnish.
Download and print our Traditional Oils Recommendation Listhere.