Solvent-Free Oil Painting with Gamblin and M. Graham & Co.
There is nothing more natural and enduring than oil painting.
For 600 years, oil colors have been made by grinding pigment into vegetable oil (most commonly linseed oil). Linseed oil is pressed from the seeds of the flax plant. The flax plant has been the heart and soul of oil painting, giving us both the oil our colors are bound in and – from the stalks of the plant – the linen we paint on.
Our mission is to lead oil painting into the future. For years, we’ve offered a range of contemporary painting mediums around fast-drying, soy-based alkyd resin, which are formulated with the mildest solvent available: Gamsol. As a thinner and brush-cleaner, Gamsol has set the standard for studio safety and allows painters to work in traditional and contemporary painting techniques.
Though many painters have adopted Gamsol, we have worked with other painters who want to eliminate all solvent from their painting processes. It is in this spirit that we introduced a range of Solvent-Free Painting Mediums, to give painters more possibilities in solvent-free techniques, with less compromise. This page discusses our range of Solvent-Free materials (Solvent-Free Gel, Solvent-Free Fluid and Safflower Oil) and helps painters navigate their use in the painting process.
Linseed and Safflower Oils
Linseed oil naturally dries faster than other oils and retains greater strength and flexibility as it ages. Paler safflower oil is used in some colors, most notably white. Not only are both of these vegetable oils completely non-toxic, but they are also both used in moisturizers, cooking oils, food and vitamins.
Linseed and safflower oils do not give off “fumes.” In fact, these oils take in oxygen as part of their drying process. Gamblin Artist’s Oil Colors do not contain solvent, nor do they require any solvent for their use. Simply put, our oil colors have always been Solvent-Free.
Solvent-Free Gel and Solvent-Free Fluid are painting mediums made from safflower oil and alkyd resin with no solvent. Why safflower? We chose safflower for these mediums because of its paler color. The alkyd resin, which is essentially a highly polymerized oil, accounts for the faster drying rate of these materials, compared to either linseed or safflower oils used alone. In regards to their drying, these mediums have a “moderately fast” drying rate – meaning that thin layers will dry to the touch in approximately 36 – 48 hours. Because they rely solely on oxidation to dry, they have a longer working time compared to our Galkyd mediums, which begin to tack up as their Gamsol content evaporates from paint layers.
As part of our Solvent-Free system, we’ve also made straight Safflower Oil available for brush cleaning and creating slower-drying mediums.
The biggest difference between the Solvent-Free Fluid and the Gel is their consistency. The Fluid medium more significantly increases the flow of oil colors off of the brush. In terms of its working properties, it is similar to either straight linseed or safflower, though faster-drying. Brush-marks will be slightly leveled, or “rounded” when using the Fluid.
Of all the mediums we make, Solvent-Free Gel is the densest, closely resembling the paint from the tube. Though it will increase the flow off the brush to some degree, its gel consistency will retain sharp, defined brush-marks. For painters who prefer to use just a little medium to give their colors a more buttery feel, Solvent-Free Gel is perfect.
Both Solvent-Free Fluid and Gel increase the flow of oil colors, increase transparency, gloss and color saturation.
Putting Solvent-Free Mediums to use
In offering this range of Solvent-Free materials, we feel it’s important to discuss their role in painting techniques, as well as their limitations. Like any painting medium, their primary function is to modify the consistency (working properties) of the oil colors from the tube.
Similar to drying oils used straight, Solvent-Free Gel and Solvent-Free Fluid are 100% fat. Like any oil-rich medium, they should be used in moderation – we recommend up to 25% by volume in mixture with oil colors and applying these mixtures thinly. Due to these limitations, Solvent-Free materials are best suited for direct, or “alla prima,” painting styles – which is what most of us are doing, most of the time.
Solvent-Free Gel, in particular, has become popular among plein air painters because of its ability to retain painterly brush-marks and increase the saturation of colors. In addition, it has the practical benefit of being packed in checked luggage for painters traveling with their painting materials.
Limitations of Solvent-Free Painting
For painting techniques that call for thin washes of color, especially in the preliminary stages of a painting, Solvent-Free mediums are not appropriate. Again, these oil-rich mediums should be used in moderation with colors from the tube. In maintaining Fat Over Lean, regard these mediums as “fat.” For underpainting techniques, consider using oil colors straight from the tube or thinned with a small amount of Gamsol or a thin, fluid medium such as Galkyd Slow Dry. A little goes a long way; oil colors relax immediately when a little Gamsol or Galkyd Slow Dry is added.
For glazing techniques where more painting medium is required for creating deep, transparent glaze layers, we recommend our Galkyd painting mediums because of their balance of oil (alkyd resin) and solvent (Gamsol). Galkyd, Galkyd Lite and Neo Megilp are all excellent glazing mediums.
Because the use of Gamsol and other solvents is so closely linked to brush cleaning, it is important for us to discuss the ins and outs of brush cleaning without the use of solvents. To this end, many painters have incorporated either mineral oil and/or “green/natural” solvent-alternatives for removing color from brushes during painting sessions. It is our stance that a material used for this purpose should do one of two things – either evaporate entirely out of paint layers (like Gamsol does), or contribute to the drying of the resulting paint layers. Mineral oil or cooking oil are non-drying and should not be incorporated into painting sessions, as even small amounts can interfere with drying. Many solvent-alternatives on the market do not evaporate completely and leave behind sticky/discolored residues in paint layers. These are best left out of the painting process entirely.
Gamblin Safflower Oil is ideal for cleaning brushes during solvent-free painting sessions. By using a simple “two rag” system outlined below, painters can reduce the amount of pigment that gets into their cleaning oil, and thus prolong its usefulness.
For brush clean-up during your painting session, first, wipe excess paint from brushes with a rag. Then dip your brush in a container of Gamblin Safflower Oil. Next, wipe the safflower oil and any remaining pigment from your brush with a second rag and continue painting.
After your painting session, brushes can be further cleaned using Gamsol and/or soap and water.
Please note that oil-soaked rags should be – at a minimum – properly stored in an Oily Rag Safety Can (such as those offered by JustRite™) until they can be thrown out. Even better, soak rags in water, and place them in an old jar or similar container and dispose of them outside in your household trashcan or apartment building dumpster.
Using either Gamsol or Safflower Oil for brush cleaning prevents pigments from being poured down the drain and contaminating the watershed. Additional information can be found on our page Oil Paint Brush Cleaning Tips.
We hope this information helps you navigate the world of Solvent-Free Oil Painting, and ultimately, create the safest painting studio possible.
From M. Graham & CO:
Solvent Free Painting
The best approach to solvent free painting is to execute the painting in one application, thinning the color with a small quantity of Walnut Oil or Walnut Alkyd Medium. For the greatest permanence, the colors should be applied thinly. When multiple layers of color are required, the technique is quite simple if a few rules are remembered.
Paint Thinly – Heavy applications of color are too massive to age well and are generally liable to wrinkle or cause cracking. It is better to apply color in a fashion that assures that the canvas texture is not lost.
Fat over Lean – or flexible over inflexible. The first coat of color should have little or no medium. Each successive layer should have slightly more oil or medium added to it than the underlying coat.
Thick over Thin – Thicker layers of color can be applied over thinner layers of color. Often when thin layers of color are applied over thicker layers cracking can occur. (Zinc White acts as though it has a high oil content and must be used carefully in underlying applications. It is not generally recommended for use in underpainting unless applied very thinly on a porous ground and allowed to dry thoroughly.)
Note: Glazes applied with appreciable quantities of medium in exceptionally thin layers are an exception to this rule.
Slow over Fast – Slow drying colors such as Titanium White, Cadmium Red, etc. should be applied over faster drying colors such as Burnt Umber to avoid cracking. In addition, sufficient time should be allowed for the underlying layer to dry thoroughly.
Use a sufficiently porous ground with “tooth”…oil colors adhere by mechanical adhesion. This requires a ground coat with some surface irregularity that the oil can sink into. Gesso should be applied thinly to preserve the texture of the surface for adhesion of the color.
Use the same medium throughout the painting…this will help to avoid difficulties in the painting structure that can lead to cracking due to uneven drying rates.