PHOENIX Oil Paint Thinner - 8.5 Fl Oz./ 250ml Oil Brush Cleaner, Odorless Painting Diluent, Mineral Spirits Refined Solvent, Painting Medium for Artists

Why I reached for this thinner

I returned to oils after a long stretch working in acrylics, and the first roadblock was obvious: fumes. I love the luminosity of oil paint, but I don’t love a studio that smells like a hardware store. I picked up the Phoenix thinner (the 8.5 fl oz/250 ml bottle) looking for a low-odor way to thin paint for underpaintings and clean brushes without dismantling my ventilation system for every session. After several weeks of steady use, it’s become the solvent I keep within arm’s reach.

What it is—and what it isn’t

Phoenix’s thinner is a refined, odorless mineral spirits (hydrotreated petroleum distillate) designed for oil painting. It’s not a drying oil or a fat medium—so it won’t add gloss or flexibility the way linseed, walnut, or alkyd mediums do. Think of it as a tool for two jobs:
- Thinning paint in lean layers to improve flow and transparency.
- Cleaning brushes and tools efficiently without harsh fumes.

If you’re looking to enrich gloss, increase “fat,” or speed drying, you’ll still want an oil or alkyd medium alongside this. Used correctly, though, it’s an excellent solvent base for underpainting, block-ins, and general brush maintenance.

Handling and first impressions

The bottle is compact, sturdy, and seals tightly enough for everyday studio use. The fluid itself is water-clear, which is what you want in a high-quality OMS: no tint, no residue. When opened, I detected a faint solvent note only at close range—nothing that lingered in the room. Compared to traditional turpentine, the difference is substantial. With a window cracked or a small fan circulating air, I was able to work comfortably for long sessions.

Evaporation is moderate. It flashes off more slowly than turpentine but fast enough that a thinly thinned wash will set up within a reasonable timeframe. That balance helped me avoid puddling while still keeping blends workable for a few minutes.

In the studio: thinning performance

I tested the thinner across three common scenarios:

1) Underpainting and block-ins

Mixed at roughly 1:1 with paint for the first pass, it laid down smooth, even veils of color without beading or uneven sheens. Pigment integrity felt intact—no chalkiness, and no obvious loss of saturation once dry. On absorbent grounds, I got crisp, stain-like layers perfect for mapping values and temperatures.

2) Controlled glazing in lean passages

For delicate veils, I used a small amount (a few drops) to relax paint without destroying body. It kept edges soft and transitioned well into subsequent fat layers—provided I respected fat-over-lean and didn’t over-thin. If you push beyond ~25–30% solvent in later stages, film integrity can suffer; that’s true of any OMS. The Phoenix thinner did its job cleanly and predictably.

3) Knife work and accidental build-up

For palettes gummed up with half-dry mixes, this solvent cut through fresh paint quickly. It’s not magic against fully cured oil films, but on “tacky” residues it restored a clean mixing surface with minimal scrubbing.

Notably, I didn’t observe any oily residue once the solvent evaporated, which reduces the risk of adhesion problems. Colors remained true once dry, and I didn’t see differential gloss caused by contaminants.

Brush cleaning

Where this thinner shines is cleanup. I used a two-jar system:
- Jar A: dirty stage to release bulk pigment.
- Jar B: cleaner stage to finish.
- Followed by a quick wash with brush soap and water.

The Phoenix thinner made quick work of fresh paint in both natural and synthetic bristles. It’s gentler than turpentine on natural hair; I noticed less squeakiness and stiffness after cleaning and conditioning. With hog bristles, it stripped paint without splaying; with sable/synthetic, it avoided the harsh drying that some stronger solvents cause. As with any OMS, follow with a proper soap to keep bristles conditioned.

Pro tip: let jar A sit overnight and decant the clear solvent off the top the next day. You can reuse a surprising amount, which makes a 250 ml bottle go further and reduces waste.

Health, safety, and ventilation

“Odorless” doesn’t mean “no ventilation needed.” The Phoenix thinner is far friendlier to work with than turpentine, but it’s still a solvent:
- Work with some airflow. A cracked window and a small fan go a long way.
- Keep away from open flames and heat sources; it’s flammable.
- Do not pour used solvent down the drain. Store spent thinner in a sealed container and dispose of it according to local hazardous waste rules.
- The product conforms to ASTM D4236, which covers labeling for chronic hazards in art materials. That’s reassuring, but common-sense precautions still apply.

Compatibility and quirks

• Paints: I tried it with a range of student and artist-grade oils (earths, cadmiums, ultramarines, modern organic pigments). No issues with separation or curdling; flow was consistent.
• Grounds: Worked well over acrylic gesso and oil-primed linen. On very thirsty grounds, it can sink in fast—consider sealing or using a little less solvent in the first pass.
• Mediums: Plays nicely with most alkyds and traditional oils when used sparingly in lean layers. Use oil-based mediums, not this solvent, to build later layers.
• Plastics and finishes: Like any OMS, it can cloud or soften some plastics, varnishes, and shellac-based finishes. Keep it off varnished furniture and avoid storing it in untested plastic jars.

Bottle and size considerations

At 8.5 fl oz (250 ml), the bottle sits in a sweet spot: large enough for frequent sessions if you’re economical, but small enough to keep on a crowded table. If you clean dozens of brushes daily, you’ll go through it faster. A dedicated brush-washing jar and decanting practice stretch the supply considerably.

The cap on my bottle sealed reliably and poured without dribbling. For precision, I still recommend transferring to a solvent dispenser or using a solvent-saving jar with a gasketed lid; those not only minimize evaporation but also reduce exposure and spills.

Value and alternatives

Artist-grade odorless mineral spirits cost more than hardware-store mineral spirits, and the Phoenix thinner tracks with that reality. You pay for refining that reduces aromatic compounds (the stuff that causes much of the odor and irritation) and improves consistency for art applications.

If you paint in small spaces, teach classes, or just prefer a calmer studio environment, the reduced odor and predictable behavior are worth the premium. If you work exclusively outdoors and prioritize cost above comfort, cheaper OMS from a hardware store can function—but they rarely match the low-odor profile and may leave residues.

Compared to turpentine, Phoenix’s thinner is far more pleasant to use, less aggressive on brushes, and less likely to irritate eyes and airways. Turpentine still wins at lifting stubborn, semi-cured films—but that’s a niche need, not a daily one.

Who it’s best for

• Indoor painters who want a quieter, cleaner solvent experience.
• Artists building lean underpaintings and transparent block-ins.
• Anyone sensitive to turpentine or heavy fumes.
• Students and teachers who need a classroom-friendly setup with proper ventilation.

Less ideal for:
- Painters seeking a medium to add body, gloss, or flexibility (use oil or alkyd instead).
- Heavy impasto cleanup on cured paint films (you’ll need a stronger approach).

Tips for best results

• Keep solvent use for early, lean layers. Transition to oil or alkyd mediums as you build.
• Try a two-jar cleaning system and decant to reuse clean solvent.
• Use a solvent-safe cleaning jar with a tight lid to limit evaporation.
• Avoid saturating the brush with solvent before picking up paint; a small amount goes a long way.
• Ventilate lightly but consistently; a slow, steady exchange of air is more comfortable than gusts.

The bottom line

I recommend the Phoenix thinner. It strikes a thoughtful balance: low odor without sacrificing cleaning power, clean evaporation without residue, and predictable behavior when thinning paints for lean passages. It won’t replace an oil or alkyd medium for later layers—and it isn’t meant to—but as a day-to-day studio solvent, it’s reliable, comfortable to use, and kinder to brushes than the old standbys. If you value a more breathable studio and a solvent that does its job without getting in the way, this belongs on your cart.