Quick answer: Gamblin Solvent-Free Gel is an alkyd-based oil painting medium made from safflower oil and alkyd resin, with no solvent. To use it, squeeze a small amount onto the palette and mix it into oil paint with a palette knife at up to about one part gel to three parts paint (roughly 25 percent by volume). It makes the paint more fluid and glossy, speeds drying to a touch-dry state in about a day for most colors, holds brushstrokes and impasto texture, and increases transparency for glazing. Use more of it in upper layers than lower ones to respect the fat-over-lean rule, and clean brushes with oil or soap rather than solvent.
Oil painters who want to work without turpentine or mineral spirits run into one problem immediately: traditional mediums are built around solvents. Gamblin’s Solvent-Free Gel is one of the products designed to fill that gap. It modifies paint handling, speeds drying, and supports layered painting, all with a material that can be used in a closed room.
This guide explains what the gel is, how to use Gamblin Solvent-Free Gel for the main oil painting tasks (thinning, glazing, impasto, layering, and faster drying), the ratios to stay within, how it compares with the brand’s other mediums, and the mistakes that cause cracking or tacky surfaces. For the broader question of how Gamblin’s paints and mediums stack up against another major brand, see our comparison of Gamblin vs Winsor & Newton.
What Solvent-Free Gel Is
According to the manufacturer’s published information, Solvent-Free Gel is made from safflower oil and alkyd resin. Those two ingredients explain its behavior.
- Safflower oil is a slow-yellowing drying oil, paler than linseed. It contributes flow and gloss.
- Alkyd resin is a synthetic oil-modified resin that dries considerably faster than natural oils alone and forms a tough, flexible film. It is the same class of material found in fast-drying oil mediums generally.
Because there is no solvent in the formula, the gel does not evaporate or thin the paint film the way a turpentine-based medium does. Instead it adds binder. The paint becomes “fatter” (more oil content), which has consequences for layering that are covered below.
The gel comes in a tube and has a soft, buttery consistency similar to oil paint itself. It is nearly colorless with a slight amber cast in the tube that is not noticeable once mixed.
What It Does to Oil Paint
| Property | Effect of adding Solvent-Free Gel |
|---|---|
| Consistency | Loosens stiff paint; becomes more fluid and brushable while still holding shape |
| Drying time | Faster; many mixtures are touch-dry in roughly 24 hours (varies by pigment, thickness, temperature) |
| Gloss | Increases; surface dries with a satin to glossy sheen |
| Transparency | Increases as more gel is added; useful for glazes |
| Texture | Holds brush marks and knife strokes rather than leveling out |
| Film strength | Alkyd adds flexibility and toughness to the dried film |
| Color | Minimal shift; safflower oil yellows less than linseed over time |
The Ratio to Stay Within
Gamblin’s general guidance for its mediums is to keep the medium at no more than about 25 percent of the paint mixture by volume, which works out to one part gel to three parts paint. Staying within that range keeps enough pigment in the film for proper drying and avoids a soft, overly glossy surface.
Practical measures on the palette:
- A pea-sized dab of gel into a grape-sized pile of paint is roughly 20 to 25 percent and is the typical working ratio.
- A smaller touch, around 10 percent, is enough to loosen stiff paint without changing its character much.
- For glazing, a higher proportion of gel to a small amount of transparent pigment is common practice, but keep the total gel in the overall layer thin, and avoid stacking many such layers quickly.
Mix with a palette knife rather than a brush. Knife mixing incorporates the gel evenly; brush mixing leaves pockets of pure gel that dry at a different rate.
How to Use It: Core Techniques
1. Loosening paint for smooth application
- Put out the paint you need for the passage.
- Add gel at about 10 to 20 percent and blend with the knife until uniform.
- Paint as normal. Brushstrokes flow more easily, edges blend more smoothly, and the paint drags less on dry underlayers.
This is the most common everyday use and replaces the few drops of solvent many painters add to stiff paint.
2. Glazing
A glaze is a thin, transparent layer of color over a dry underpainting that shifts the hue or deepens shadows without hiding what is beneath.
- Make sure the underlying layer is dry to the touch and firm.
- Mix a small amount of a transparent or semi-transparent pigment (for instance, a transparent earth, a quinacridone, or ultramarine) with gel until the mixture is translucent on the palette.
- Brush a thin, even layer over the area. A soft synthetic flat works well.
- Soften or remove excess with a clean, dry brush or a lint-free rag.
- Let it dry (usually a day or two) before glazing again.
Because the gel speeds drying, glazes can be stacked more quickly than with traditional oil-only glazing mediums.
3. Impasto and holding texture
Unlike fluid mediums that make paint level out, the gel keeps its shape. Mix it into paint for knife work or thick brushwork, and the ridges stay sharp while drying. For very thick applications, keep the gel at the lower end of the range; the paint itself supplies the body, and excess medium in a thick layer slows thorough drying.
4. Speeding drying for layered work
Alla prima painters who want to rework the next day, and layered painters who want to apply the next pass without waiting a week, add gel to every mixture on the palette. Most colors mixed with it will be touch-dry overnight in a warm, dry room. Slow-drying pigments (titanium white, some cadmiums, ivory black) benefit most; fast-drying earth colors change less.
5. Oiling out
When a dry oil painting develops dull, sunken-in patches, a thin layer of medium rubbed over the surface before continuing restores the color saturation and helps the new paint bond. Rub a very small amount of gel over the dry passage with a lint-free cloth, wipe away any excess, and paint into it.
6. Painting without solvent from start to finish
A completely solvent-free workflow using the gel looks like this:
- Underpainting: Use paint with little or no medium, applied thinly and scrubbed in. Fast-drying earth colors are ideal. If you need to thin, a small amount of gel is acceptable, though the leanest layer should stay close to paint only.
- Middle layers: Paint with about 15 to 20 percent gel.
- Final layers and glazes: Use up to the full 25 percent.
- Brush cleaning: Wipe brushes on a rag, then work them in a jar of safflower or linseed oil (or a brush-cleaning oil), wipe again, and finish with brush soap and water.
Fat Over Lean
The oldest rule in oil painting is that each layer should contain at least as much oil (fat) as the layer below it. A fat layer under a lean one dries more slowly, and the lean layer on top can crack as the one beneath continues to move.
Solvent-Free Gel adds oil and resin, so it makes paint fatter. That means:
- Use the least gel in the first layer and increase slightly with each subsequent layer.
- Do not paint a layer with no medium over a layer that had a lot of gel.
- Keep the total medium in any layer within the 25 percent guideline.
Because the alkyd component speeds drying, the gel is more forgiving of fat-over-lean mistakes than pure oil would be, but the principle still applies.
Solvent-Free Gel vs. Gamblin’s Other Mediums
Gamblin makes several mediums, and choosing the right one depends on the consistency you want.
| Medium | Consistency | Solvent? | Drying | Main use |
|---|---|---|---|---|
| Solvent-Free Gel | Soft gel, holds texture | No | Fast (alkyd) | Loosening paint, glazing, impasto, faster layers |
| Solvent-Free Fluid | Fluid, pourable | No | Fast (alkyd) | Thinner, smoother applications and fine blending |
| Galkyd | Fluid | Yes (contains petroleum solvent) | Fast | Traditional fast-drying glazing and layering |
| Galkyd Gel | Thick gel | Yes | Fast | Heavy impasto |
| Neo Megilp | Soft, silky gel | Yes | Moderate | Smooth, luminous passages, portrait work |
| Refined linseed or safflower oil | Fluid | No | Slow | Traditional slow-drying medium |
In short, the gel is the solvent-free, texture-holding option; the fluid is the solvent-free, leveling option. Many painters keep both.
Tips for Good Results
- Mix small batches. Paint with gel stiffens on the palette within hours as the alkyd starts to set. Mix what you will use in a session.
- Cover the palette or scrape it clean at the end of the day. Dried gel-paint is harder to remove than plain oil paint.
- Cap the tube tightly. Air exposure skins the gel at the nozzle; wipe the threads before capping.
- Work in a warm room. Alkyds dry more slowly in cold or humid conditions.
- Test gloss. If the finished painting has uneven sheen (some passages matte, some glossy), a final varnish after full curing evens it out.
- Allow curing time before varnishing. Touch-dry in a day does not mean cured. Follow standard oil painting practice and wait several months, or use a retouch varnish in the meantime if needed.
- Keep gel-rich mixtures thin. Thick layers with maximum medium can stay soft inside long after the surface skins.
Common Mistakes
| Mistake | What happens | Fix |
|---|---|---|
| Using more than about 25 percent gel | Soft, overly glossy film; possible wrinkling | Measure with the knife; stay at or below 1:3 |
| Heavy gel in the first layer, none on top | Fat-over-lean violation; risk of cracking | Least medium at the bottom, more above |
| Mixing with a brush | Uneven drying, streaks of pure medium | Mix thoroughly with a palette knife |
| Thick impasto loaded with gel | Surface skins while interior stays soft | Reduce gel for thick passages |
| Cleaning brushes in solvent out of habit | Unnecessary fumes; defeats the purpose | Oil, then brush soap |
| Varnishing after a week | Varnish traps uncured oil, may cloud or crack | Wait for full cure; use retouch varnish if needed |
| Expecting it to thin like turpentine | Paint stays fairly bodied | Use Solvent-Free Fluid for thinner, washier passages |
Brush and Cleanup Notes
A solvent-free medium only makes sense alongside solvent-free cleanup. Wipe excess paint from brushes onto a rag, then swish them in a jar of inexpensive safflower or linseed oil, wipe again, and wash with brush soap or a bar of plain soap under warm water until the lather runs clean. Reshape and dry flat. Oil-soaked rags should be spread flat outdoors to dry or stored in a sealed metal container; piled oily rags can self-heat.
Synthetic brushes designed for oils hold up well to this routine. If you are weighing brush options for solvent-free oil work, our look at whether Winsor & Newton brushes are good covers bristle and synthetic ranges in detail.
FAQs
How much Gamblin Solvent-Free Gel should I mix with oil paint?
Up to about one part gel to three parts paint, or roughly 25 percent by volume. Smaller amounts, around 10 percent, are enough to loosen stiff paint. Staying within this range keeps the paint film sound.
Does Solvent-Free Gel speed up drying?
Yes. The alkyd resin in the gel makes most mixtures touch-dry in about a day in a warm, dry room, compared with several days for paint alone. Slow-drying pigments benefit the most.
Can I use Solvent-Free Gel for glazing?
Yes. Mixing a transparent pigment with gel makes a glossy, translucent glaze that dries quickly enough to layer within a day or two. Keep each glaze thin.
Is Gamblin Solvent-Free Gel the same as Galkyd Gel?
No. Both contain alkyd resin and speed drying, but Galkyd Gel contains petroleum solvent and is thicker, while Solvent-Free Gel contains no solvent and has a softer, buttery consistency.
Can I thin oil paint for an underpainting with Solvent-Free Gel?
You can add a small amount, but it will not produce a thin wash the way solvent does. For the leanest first layer, use paint with little or no medium, applied thinly, or use the fluid version of the medium sparingly.
How do I clean brushes after using Solvent-Free Gel?
Wipe off excess paint, work the brush in a jar of safflower or linseed oil, wipe again, then wash with brush soap and warm water. No solvent is needed.
Next Step
Solvent-Free Gel does three jobs at once: it loosens paint, speeds drying, and supports glazing and texture, all without opening a window. Keep it under a quarter of the mixture, add less in early layers and more in later ones, mix with a knife, and clean up with oil and soap. Whether Gamblin’s paints and mediums are the right system for you compared with the alternatives is a separate question, and our full breakdown of Gamblin and Winsor & Newton oil paints and mediums covers consistency, color range, mediums, and value side by side.
