Model Paints and Supplies – Acrylic, Lacquer, Enamel, and Oil Paints with Thinners, Primers, Brushes, and Airbrush Accessories
Paint is where a model kit stops being a construction project and becomes an artistic one. The plastic out of the box provides the shape — paint provides the color, the surface texture, the illusion of scale, and the weathered, lived-in quality that makes a finished model feel like a miniature version of something real rather than a toy. But model paint is not one product. It is an ecosystem of chemically distinct paint types, each with different thinning requirements, application methods, drying behaviors, compatibility rules, and ideal use cases. Using the wrong paint in the wrong context, or layering incompatible types on top of each other, produces results ranging from disappointing to destructive. Understanding what each paint type does and how they interact with each other is the most valuable technical knowledge a model builder can develop.
Paint Types and Their Chemistry
Water-based acrylics use water and acrylic polymer emulsions as their base. They are low-odor, clean up with water while wet (or isopropyl alcohol once dry), and dry through water evaporation, leaving a flexible acrylic film on the surface. Water-based acrylics are the safest paint type for indoor use without dedicated ventilation and the most forgiving for beginners — mistakes wipe off easily, thinning ratios are flexible, and the health risks during application are minimal. They brush-paint well because their formulation allows self-leveling that hides brush strokes. The primary limitations are that they are the least durable of the three main types once cured and can be reactivated by moisture or solvents even after drying, which makes them vulnerable during subsequent weathering and decaling steps unless sealed with a protective clear coat.
Alcohol-based acrylics (sometimes called hybrid acrylics or solvent-based acrylics) use alcohol and proprietary solvents rather than water as the carrying medium. They are labeled "acrylic" because the binder is an acrylic resin, but they behave differently from water-based acrylics in important ways. They dry faster, produce a harder and more durable film, and airbrush exceptionally well because the solvent evaporation produces a smooth, self-leveling finish. However, they are more difficult to brush-paint than water-based acrylics because the fast drying time does not allow enough working time for brush strokes to level out. Thinning with lacquer thinner or isopropyl alcohol rather than water produces the best airbrushing results. These paints are extremely popular in the Gunpla and scale modeling community because they combine the accessibility of acrylic with airbrush performance that approaches lacquer.
Lacquer paints use aggressive solvents (xylene, toluene, butyl acetate, or proprietary lacquer thinners) that partially dissolve the plastic surface on contact, creating a chemical bond between paint and substrate that is stronger and more durable than the mechanical adhesion of acrylics. Lacquers produce the smoothest finish when airbrushed, dry extremely fast, and cure to a hard film that resists handling, masking tape, and the solvents used in subsequent enamel and oil weathering steps. These qualities make lacquer the preferred base coat paint for builders who plan to apply enamel washes, oil dot filters, and solvent-based weathering products over the base color. The tradeoff is that lacquer solvents produce harmful fumes that require a spray booth with exhaust ventilation and a half-face respirator with organic vapor cartridges during use. Lacquers are not safe for indoor use without this equipment.
Enamel paints use petroleum-based solvents (mineral spirits, white spirit, or dedicated enamel thinners) and cure through a slow chemical oxidation process rather than simple solvent evaporation. The extended working time — enamels remain manipulable on the surface for significantly longer than acrylics or lacquers — makes them the best paint type for washes (thinned paint flowed into recessed detail for shadow effects), filters (extremely thin paint applied over a base coat to shift its color tone), and brush-painted detail work where self-leveling and a forgiving working window matter more than fast drying. Enamels produce durable, vibrant finishes and are used for both full base coats and detail-level applications depending on the builder's workflow.
Oil paints are artist-grade pigments suspended in linseed or safflower oil. In scale modeling, they are used almost exclusively for advanced weathering techniques — dot filtering, streaking, blending, and fading — because their extremely long open time (hours to days before they set) allows the builder to manipulate, blend, and remove the paint directly on the model surface with brushes, sponges, and solvent-dampened tools. Oils must be applied over a fully cured, sealed base coat (typically a gloss or satin clear coat) that protects the underlying paint layers from the oil solvents.
The Compatibility Rule: What Goes Over What
The single most important technical rule in model painting is the layering compatibility hierarchy. Different paint types use different solvents, and a stronger solvent applied over a weaker paint layer will dissolve, soften, wrinkle, or lift the paint underneath. The rule is simple:
Lacquer can be used as a base coat under anything. Acrylic, enamel, and oil paints can all be safely applied over a fully cured lacquer base because none of their solvents are strong enough to attack the cured lacquer film. This is why lacquer is the professional-level base coat paint — it creates a bulletproof foundation for every subsequent step.
Enamel can be used as a base coat under acrylic and oil. Enamel solvents are weaker than lacquer solvents, so acrylic applied over enamel is generally safe once the enamel has fully cured (which takes longer than touch-dry — allow at least 24 to 48 hours for full cure). However, enamel should never be used under lacquer, because lacquer solvents will attack and dissolve the enamel layer.
Acrylic is the weakest base. It can be applied over lacquer and enamel safely, but using enamel or lacquer over an acrylic base is risky. Enamel thinners can soften some acrylic films (results vary by brand and specific formulation), and lacquer solvents will almost certainly destroy an acrylic base coat. If acrylic is used as the base coat and enamel weathering is planned, sealing the acrylic with a clear coat (an acrylic gloss coat or a very lightly misted lacquer coat) before applying enamel products adds a protective barrier that reduces the risk.
The practical summary: lacquer base → acrylic or enamel detail → enamel wash → oil weathering is the most robust and widely used layering sequence in scale modeling. Each step uses a weaker solvent than the layer below it, which means cleanup and corrections at each stage can be done without damaging previous work.
Thinning for Airbrush and Brush
Almost no model paint sprays well directly from the bottle. Thinning to the correct viscosity for your application method is essential for smooth, even coverage without clogging, spattering, or texture problems.
For airbrushing, the target consistency is often described as "skim milk" — thin enough to flow through a 0.3mm to 0.5mm needle without resistance, but pigment-dense enough to cover in two to three thin passes. General starting ratios are approximately 1:1 to 1:2 paint to thinner for most acrylics, 1:1 to 1:1.5 for lacquers, and 2:1 to 1:1 for enamels, though exact ratios vary by brand, color (some pigments are denser than others), and the specific thinner used. These are starting points — the correct ratio for any specific combination is confirmed by test-spraying on a piece of scrap plastic or a plastic spoon before committing to the model.
For brush painting, paint should be thinned less than for airbrushing — roughly a few drops of thinner per brush load — just enough to improve flow and self-leveling without making the paint so thin that it runs or takes excessive coats to achieve opacity. Water-based acrylics are the most brush-friendly because their longer open time and water-soluble formula allow brush strokes to level out before the paint skins over. Adding a drop of retarder (a drying-time extender) to any acrylic paint further improves brush painting by slowing the drying enough to prevent visible stroke marks. Enamels are also excellent for brush painting because their naturally slow cure provides ample leveling time without any additive.
Using the correct thinner for the paint type matters. Water-based acrylics thin with water, distilled water, or brand-specific acrylic thinner. Alcohol-based acrylics thin with isopropyl alcohol, lacquer thinner, or brand-specific thinner (not water — water can be added in small amounts to some formulations but will not properly reduce the acrylic binders). Lacquers thin with lacquer thinner or brand-specific lacquer thinner. Enamels thin with mineral spirits, white spirit, or brand-specific enamel thinner. Cross-contaminating thinners — using lacquer thinner in water-based acrylic, for example — can cause clumping, separation, or unpredictable results.
Primers and Surface Preparation
Primer serves three functions: it creates a uniform color base that allows the top coat to cover evenly, it provides a micro-textured surface that paint adheres to better than bare plastic, and it reveals surface imperfections (seam lines, mold marks, sink marks, scratches) that are invisible on raw plastic but become obvious once covered with a uniform coat. Skipping primer is the most common shortcut that undermines an otherwise well-executed paint job — paint applied directly to bare plastic covers unevenly, chips more easily, and fails to hide the imperfections that primer would have caught at a correctable stage.
Grey primer is the most versatile — it works under any paint color without significantly affecting the final hue. White primer is used under bright and pastel colors that need a light base to appear vibrant (reds, yellows, and oranges are particularly sensitive to the undercoat color). Black primer is used for dark color schemes and for the pre-shading technique, where black primer is applied first and the top coat is sprayed in progressively lighter passes, allowing the black to show through at panel line edges and recesses to create built-in shadow without additional weathering. Surfacer — a thicker primer variant available in grits (typically 500, 1000, and 1500) — fills minor surface imperfections that standard primer cannot cover, reducing the sanding steps needed to achieve a smooth surface.
Clear Coats, Sealers, and Protection
A clear coat (topcoat) applied over a finished paint job serves both an aesthetic and a protective function. Gloss clear produces a high-shine surface suited to automotive finishes, candy coats, and any subject that should look polished and reflective. It is also the required surface preparation before applying decals — decals applied over a gloss surface conform tightly and avoid silvering (the visible air trapped under a decal's edges when applied over a matte or textured surface). Matte clear eliminates all gloss and produces the flat, non-reflective finish that is realistic for military vehicles, construction equipment, mecha, and most subjects that would not appear shiny in real life. Satin clear produces a subtle sheen between matte and gloss — the most natural-looking finish for most subjects because real-world surfaces are rarely perfectly matte or perfectly glossy.
The standard finishing workflow is: base coat → gloss clear → decals → gloss clear over decals to seal them → weathering (washes, filters, pigments) → final matte or satin clear to unify the surface sheen and seal everything. This sequence ensures that decals sit smoothly on a gloss surface, weathering products are applied over a protective sealed layer, and the final coat ties the entire model together with a consistent finish.
Brushes, Mixing, and Accessories
Synthetic brushes in round and flat profiles are the workhorse tools for hand-painting model kits. Round brushes in sizes 0, 1, and 2 handle most detail work. Flat brushes in 4 to 8mm widths handle base coating of small parts and flat surfaces. Fine-point brushes (10/0, 5/0) handle eyes, instrument panels, and micro-detail that standard brushes cannot reach. Natural-hair brushes (kolinsky sable) hold more paint and produce smoother strokes than synthetics, but they are significantly more expensive and require more careful maintenance. For beginners, a quality synthetic set is more than sufficient.
Mixing supplies include paint palettes (or disposable palette paper) for mixing custom colors, stirring sticks for homogenizing settled pigments in the bottle before use, empty dropper bottles for pre-mixing custom colors or pre-thinned airbrush-ready batches, and pipettes or eyedroppers for precise thinner measurement. Masking tape (low-tack hobby tape in 1mm to 6mm widths) is used to create sharp paint boundaries between colors — the tape is applied over a fully dry coat, the adjacent color is painted, and the tape is removed to reveal a clean, crisp line. Masking fluid (liquid mask) is brushed onto irregular shapes that tape cannot cover, dries to a peelable rubber film, and is removed after painting to reveal the protected surface underneath.
Cleanup and Maintenance
Cleaning brushes and airbrushes immediately after use is the single most important maintenance habit in model painting. Dried paint in a brush ruins the tip shape permanently. Dried paint in an airbrush clogs the needle, nozzle, and internal passages and requires full disassembly to clear. Water-based acrylics clean up with water while wet and with isopropyl alcohol once dry. Alcohol-based acrylics clean up with isopropyl alcohol or lacquer thinner. Lacquers clean up with lacquer thinner. Enamels clean up with enamel thinner or mineral spirits. Running the appropriate cleaning solvent through an airbrush after every color change and at the end of every painting session keeps the internal passages clear and extends the life of the airbrush indefinitely.
For the kits these paints are applied to, model kits covers the full range of Gundam, mecha, sci-fi, and anime builds. For the tools used alongside paint, hobby tools and equipment includes nippers, knives, files, cutting mats, and airbrush systems. For post-paint finishing effects, effects and textures covers weathering pigments, panel lining products, and metallic finishes. For surface preparation before paint, preparation and finishing covers primers, surfacers, putty, and sanding materials.
