ForMatter/Materials/paint/Automotive Paint — Acrylic Enamel (single-stage)

mat_automotive_paint_acrylic_enamel

Automotive Paint — Acrylic Enamel (single-stage)

automotive coating chemistry — single-stage enamel family (~1957–early 1980s OEM) · acrylic enamel, single-stage enamel, factory enamel, muscle-car paint chemistry

highlast updated 2026-04-29

The chemistry that painted American muscle cars. Single-stage acrylic enamel — pigment + acrylic resin + solvent + (sometimes) a hardener — sprayed in two coats, baked, done. The color and the gloss are the same film: there's no clearcoat over the top. This is the chemistry behind every Chrysler high-impact paint code (FE5 Bright Red / Rallye Red, FJ5 Sublime / Limelight, EV2 HEMI Orange / TorRed, FC7 In-Violet / Plum Crazy, FY1 Lemon Twist / Yellow), GM's late-1960s and 1970s passenger-car paint codes, and Ford's M-codes from the same era. Acrylic enamel reads softer and slightly chalkier than modern basecoat-clearcoat — a 1970 Plum Crazy looks like a 1970 photograph for a reason. UV chalking and fade are the canonical failure modes; a 1972 paint job that's been outside since 1972 looks dramatically different from one that was repainted in 2005, even if the formula is the same.

Solvent-borne single-stage pigmented enamel. Binder is thermosetting acrylic resin (often modified with melamine for crosslink), pigment 25–45 percent by weight, solvent (xylene / mineral spirits / butyl cellosolve blend) 35–50 percent. Cure mechanism: solvent flash + oxidative or melamine crosslink at bake temperature (140–160 °C OEM bake; refinish air-dry or 60 °C low-bake with isocyanate hardener). Two-coat application typical at OEM, three coats common in refinish; dry film 50–80 µm total. VOC content high (450–600 g/L); largely phased out of US OEM by ~1985 in favor of basecoat-clearcoat; retained in industrial / agricultural / fleet refinish where the trade-off favors color-and-gloss-in-one-film. Single-stage means no clearcoat — touching the cured film touches the pigmented coat directly; spot repair is straightforward (no clearcoat to blend) but UV protection lives in the same film as the pigment, so chalking eventually dulls the gloss and fades the color. The 1970 Mopar high-impact program is the best-documented application of this chemistry: vivid pigments (often containing lead-chromate yellows, organic reds, phthalocyanine blues — the period chemistry that gave the colors their saturation) sprayed as single-stage enamel and never refinished today without changing the chemistry to BC/CC. Restoration suppliers maintain code-matched single-stage formulas (PPG Deltron DCC, Sherwin-Williams Dimension, Glasurit Series 22) for concours-faithful refinish.

chemistry

binderthermosetting acrylic resin, often melamine-crosslinked
cure_mechanismbake-cure (OEM 140–160 °C) or air-dry / hardener-catalyzed (refinish)
voc_g_l_typical525
stages1

source: PPG / Glasurit single-stage technical literature; SAE J1545.

history

oem_introduction1957 (DuPont's first acrylic enamel on Chrysler / GM bodies)
muscle_era_peak1968–1972 (the Mopar high-impact program; Ford's M-codes; GM's saturated-color era)
oem_phase_outearly-to-mid 1980s (replaced by BC/CC for clearcoat depth + chip resistance)

source: Hagerty / Hemmings paint-history features; PPG Refinish corporate history.

PBR starter values

finish · glossy — open for table, JSON, host snippets, downloads

Principled BSDF defaults derived from the sphere glossy finish. Reasonable seed for Blender, Substance, Keyshot, Rhino — tune per material. Or grab the whole library at once: ForMaterials library →

# finish:                   glossy
albedo                      #8a2825
metallic                    0.00
roughness                   0.15
ior                         1.45
transmission                0.00
clearcoat                   0.30
sheen                       0.00
anisotropic                 0.00

copy as JSON

{
  "albedo": "#8a2825",
  "metallic": 0.0,
  "roughness": 0.15,
  "ior": 1.45,
  "transmission": 0.0,
  "clearcoat": 0.3,
  "sheen": 0.0,
  "anisotropic": 0.0
}

Blender 4.x Python

# Blender 4.x — Principled BSDF
# Automotive Paint — Acrylic Enamel (single-stage) · finish: glossy
import bpy
mat = bpy.data.materials.new(name="mat_automotive_paint_acrylic_enamel")
mat.use_nodes = True
bsdf = mat.node_tree.nodes["Principled BSDF"]
bsdf.inputs["Base Color"].default_value         = (0.2542, 0.0212, 0.0185, 1.0)
bsdf.inputs["Metallic"].default_value           = 0.000
bsdf.inputs["Roughness"].default_value          = 0.150
bsdf.inputs["IOR"].default_value                = 1.450
bsdf.inputs["Transmission Weight"].default_value = 0.000
bsdf.inputs["Coat Weight"].default_value        = 0.300
bsdf.inputs["Sheen Weight"].default_value       = 0.000
bsdf.inputs["Anisotropic"].default_value        = 0.000

KeyShot Python (lux)

# KeyShot 11+ — lux Python API, Generic material
# Automotive Paint — Acrylic Enamel (single-stage) · finish: glossy
# Run from Window → Scripting Console
import lux
mat = lux.createMaterial(name="mat_automotive_paint_acrylic_enamel", materialType="Generic")
mat.setProperty("diffuse",      (138, 40, 37))   # 8-bit sRGB
mat.setProperty("metallic",     0.000)
mat.setProperty("roughness",    0.150)
mat.setProperty("indexOfRefraction", 1.450)
mat.setProperty("transparency", 0.000)
mat.setProperty("coatingWeight", 0.300)

Substance pbrMetalRough

{
  "_format": "Substance Designer / Painter \u2014 pbrMetalRough constants",
  "_about": "Automotive Paint \u2014 Acrylic Enamel (single-stage) \u00b7 finish: glossy",
  "baseColor": {
    "r": 0.2542,
    "g": 0.0212,
    "b": 0.0185
  },
  "metallic": 0.0,
  "roughness": 0.15,
  "ior": 1.45,
  "opacity": 1.0,
  "anisotropyLevel": 0.0,
  "_notes": "Channels listed are the standard Substance pbrMetalRough output. Drop into a Uniform Color node per channel, or as the constant input on a layered stack."
}

glTF 2.0 Metallic-Roughness

{
  "asset": {
    "version": "2.0",
    "generator": "ForMatter"
  },
  "materials": [
    {
      "name": "mat_automotive_paint_acrylic_enamel",
      "pbrMetallicRoughness": {
        "baseColorFactor": [
          0.2542,
          0.0212,
          0.0185,
          1.0
        ],
        "metallicFactor": 0.0,
        "roughnessFactor": 0.15
      },
      "extensions": {
        "KHR_materials_ior": {
          "ior": 1.45
        },
        "KHR_materials_clearcoat": {
          "clearcoatFactor": 0.3
        }
      }
    }
  ]
}

USD Preview Surface

# USD Preview Surface — UsdShade.MaterialLook prim attributes
# Automotive Paint — Acrylic Enamel (single-stage) · finish: glossy
def Material "mat_automotive_paint_acrylic_enamel" {
    token outputs:surface.connect = </mat_automotive_paint_acrylic_enamel/PreviewSurface.outputs:surface>

    def Shader "PreviewSurface" {
        uniform token info:id = "UsdPreviewSurface"
        color3f inputs:diffuseColor = (0.2542, 0.0212, 0.0185)
        float   inputs:metallic     = 0.000
        float   inputs:roughness    = 0.150
        float   inputs:ior          = 1.450
        float   inputs:opacity      = 1.000
        float   inputs:clearcoat    = 0.300
        token   outputs:surface
    }
}

↓ download glTF material

ProcessAutomotive Paint Application (OEM Body, Refinish, Restoration)

Substitutes

Automotive Paint — Nitrocellulose / Acrylic Lacquer

Automotive Paint — Basecoat / Clearcoat (BC-CC, 2K Urethane)

Where to buyhttps://www.tcpglobal.com/

An example from this chemistry

1970 Dodge Super Bee (Phil's car)

FE5 Bright Red

How it was painted — Hamtramck Assembly downdraft booth, body hung on conveyor, sprayed by line operators with siphon-feed guns at ~50 psi. Single-stage acrylic enamel from PPG / DuPont in 2 coats, 50–60 µm total dry film, no clearcoat. Bake at 150 °C for ~25 min in the line oven. Color and gloss are the same film. Polish was minimal — the gun finish was the production finish. Body shell got a phosphate dip and a single primer coat before color; no e-coat (electrocoat had been pioneered by Ford in 1963 but wasn't yet universal).

What it means for owners — A 1970 Super Bee paint job that has been outdoors since 1970 has a distinctive soft chalk and minor fade — the UV stabilization in 1970 enamel was much weaker than modern coatings. Fresh repaints (1990s+) frequently use BC/CC chemistry under the original FE5 color formula, which reads visibly different from a survivor car: deeper, glossier, more obviously modern. The concours community has split on which is correct — a chemistry-faithful single-stage enamel respray, or a BC/CC respray that holds up better in service.

Source: Plenum encyclopedia (paint-fe5); Galen Govier registry; Hagerty 'How muscle cars were painted'.

Colors in this chemistry · 61

Chrysler B-body / E-body / A-body factory paint codes 1968-1974, single-stage acrylic enamel chemistry. Sourced from Plenum's Chrysler decode vocabulary; codes are facts (not copyrightable). The famous high-impact set (FE5, FJ5, EV2, FC7, FY1, FM3, FJ6, EK2) and the surrounding palette of metallic and solid colors.

The famous codes

EV2 HEMI Orange (Dodge) / TorRed (Plymouth) — carryover ↗
1970, 1971, 1972, 1973 · solid
High-impact orange. Per Dodge Garage's high-impact retrospective, Plymouth's name is 'TorRed' (one word, no hyphen), Dodge's is 'HEMI Orange' (capitalized). Spans 1969–1972 in production.
FC7 Plum Crazy (Dodge) / In-Violet (Plymouth) ↗
1970, 1971 · solid
High-impact purple. Per Dodge Garage's high-impact retrospective.
FE5 Bright Red (Dodge) / Rallye Red (Plymouth) ↗
1970, 1971, 1972, 1973, 1974 · solid
Historic Ditzler/PPG cross-reference per mymopar.com paint chart. Verify against your supplier's current Concept / OneChoice formulary.
FJ5 Sublime (Dodge) / Limelight (Plymouth) ↗
1970 · solid
High-impact lime green, mid-1970 introduction, 1970-only code. Per Dodge Garage's own retrospective on the 1970 high-impact program: Dodge marketed FJ5 as 'Sublime', Plymouth as 'Limelight'. Often confused with FJ6 (Sassy Grass / Green Go), which is a deeper saturated green; in person FJ5 reads as a luminous citrus-lime where FJ6 reads as a meadow green.
FJ6 Sassy Grass (Dodge) / Green Go (Plymouth) ↗
1970 · solid
High-impact saturated green, the deeper sibling to FJ5. Per Dodge Garage's high-impact retrospective: Dodge marketed FJ6 as 'Sassy Grass', Plymouth as 'Green Go'. Renamed GF7 for 1971; final year 1972 in tiny volumes.
FY1 Top Banana (Dodge) / Lemon Twist (Plymouth) ↗
1970 · solid
Per mymopar.com paint chart.
GF7 Sassy Grass (Dodge) / Green Go (Plymouth) — 1971 carryover of FJ6 ↗
1971, 1972 · solid
GK6 Sublime (Dodge) / Limelight (Plymouth) — 1971 carryover of FJ5 ↗
1971 · solid
M6 1969 high-impact orange (precursor to EV2 HEMI Orange / TorRed) ↗
1969 · solid
Per Dodge Garage's high-impact retrospective, the EV2 Hemi Orange / TorRed family spans 1969–1972. 1969 builds may carry an older 'M6' code form; 1970 standardized on EV2 across Chrysler. The previous Plenum claim that M6 and EV2 were used 'interchangeably across plants' overstates what's directly documented and was rolled back. Confidence demoted to registry-attested pending a primary 1969 Fact Data Book scan.

The full palette

Citations

Concordance

House vocabulary — terms ForMatter uses with intent.

anisotropic: Direction-dependent. Wood reads differently along the grain than across it; rolled steel is stiffer along the rolling direction. The Principled-BSDF anisotropic input rotates the highlight to match.
anodize: Electrochemical oxide layer grown on aluminum (Type II / III), titanium, or niobium. Type II accepts dye for color; titanium / niobium use voltage-driven thin-film interference instead of dye. The CMF entry covers the seal step that locks the color in.
application: What the thing IS, in the world. The third entity, peer of material and process. A water bottle, a chair, an extruded-aluminum profile.
BRDF: Bidirectional Reflectance Distribution Function. The math behind how a surface returns light for any incoming and outgoing direction. The PBR model is a parameterized BRDF.
channeled: A voice block written within a dead author's philosophy, marked and cited. Distinct from a verbatim quote. Roland Barthes channeled on PMMA reads like Barthes; the citation attributes the lineage.
CMF: Color, Material, Finish — the trio designers specify together when handing a part off for production. ForMatter's Finish entity is the F in CMF: 10 categories — polish / anodize / patina / plate / coating / texture / cut / mold_finish / glaze / stone_finish — and 100+ entries. Every finish entry pairs to the materials and processes it suits.
choral fugue: ForMatter's register. Subject stated plainly (freshman tier), answered in technical and sensorial registers, countersubjects from linked processes and applications, citations as final stretto. Voice blocks where canon attaches.
clearcoat: A second specular layer over the base surface. Glossy plastics and lacquered woods get a clearcoat term in the PBR table. IOR 1.5 by default.
compatibility (process): Each process entry lists which materials it can work. The cross-ref renders as sphere pills so the gallery feeling extends inward.
confidence: Each entry tagged high / medium / low. A senior's low-confidence-with-three-citations beats a freshman's high-confidence-with-none. The label is a contract with the reader, not a brag.
crystalline (finish): A faceted-surface read — gemstones, glassy minerals, ice. Drives PBR defaults: IOR 2.42 (diamond), transmission 1.0, low roughness.
derive_pbr(): The build's single source of truth — sphere palette + finish enum → Principled-BSDF starter values. One function feeds the entry-page table, the per-host snippets, the glTF export, and the Three.js Live Preview.
finish (entity): ForMatter's CMF layer — surface treatments and conditions a designer chooses for a given material and process. Categories: polish, anodize, patina, plate, coating, texture, cut, mold_finish, glaze, stone_finish. Distinct from the sphere `finish` enum (metallic / matte / glossy / etc.) which is the visual register of the proxy.
freshman / senior register: Two registers in every entry — the plain freshman description and the technical / sensorial one. Same database, two readers, no extra subscription.
glTF: GL Transmission Format — the open 3D-asset standard every modern app reads. ForMatter emits a .gltf material doc per material. Open standard, designer-friendly handoff.
IOR: Index of Refraction. How much light bends entering the surface. Air 1.0, water 1.33, glass 1.5, diamond 2.42. Drives transmission and the specular term.
iridescent (finish): Hue-shifted accent over base. Anodized titanium and niobium, opal, paraíba. Drives PBR defaults: low metalness, full iridescence, clearcoat.
iridescence: Thin-film interference layer over the base material. KHR_materials_iridescence in glTF, MeshPhysicalMaterial.iridescence in Three.js. Tunable from the FOCUS slider on iridescent / pearlescent entries. The ior and thickness range together set the visible color sweep — opal uses a 100–800 nm thickness range (film, not wavelength) to span the full visible band.
lite-PBR: ForMatter's PBR approach — Principled-BSDF starter values per entry, no measured BRDFs, no commercial assets. Honest reasonable defaults from the finish enum, per-entry numeric overrides where you have a real reason.
Live Preview: The Three.js shader ball that replaces the static CSS sphere on every entry page. One render path for every category — metals, woods, polymers, ceramics, paints, textiles, gemstones, glass. Same derive_pbr() values, real-time lit by a synthetic studio environment, draggable. Optional — toggle in Preferences.
material: What the thing is MADE OF. The first entity. Aluminum 6061, white oak, soda-lime glass.
metallic (finish): Specular highlight, deep shadow rim. Drives PBR defaults: metalness 1, low roughness, IOR 1.45. Polished steel, gold, copper.
mood board: Folded into the Project workspace at /project.html. The mood-board upload, palette extraction, character chips, and matcher results all live alongside the collected items grid and the save .formatter / save PDF / open .formatter actions — one feature, one page.
Ollama: Local-LLM scaffold on the Project page. Off by default. When toggled on in Preferences AND Ollama is reachable at localhost:11434, the natural-language input box ('something soft and warm with a wet read') asks the model to translate the description into character-chip toggles. Never invents material properties; the LLM only translates intent into existing chip vocabulary. The keyword fast-path (chips alone, no LLM) is the default — see suite-wide ai-integration pattern.
project: The full workspace at /project.html — collected materials, processes, applications, finishes plus an optional mood-board image whose dominant colors search the library for matches. Save / open .formatter files round-trip the project state. Cross-conversation: the Project page replaces the slide-down panel that used to live behind the appbar 'project' button.
patina: A chemical color shift on metal — heat-blue on steel, fume-black on silver, verdigris on copper, gun-blue on tool steel, ferric on copper. CMF-layer entry; cited by both the material and the process pages that produce it.
PBR: Physically-Based Rendering. The shading model every modern 3D app uses, parameterized by metallic / roughness / IOR / transmission / clearcoat / sheen. ForMatter publishes starter values for every material entry.
SPI mold finish: Society of the Plastics Industry mold-cavity finish standard. A1 / A2 / A3 (diamond polish, mirror), B1 / B2 / B3 (paper, semi-gloss), C1 / C2 / C3 (stone, matte), D1 / D2 / D3 (dry blast, textured). The finish prints from the mold cavity onto the molded part — a designer picks the SPI grade with the molder when specifying the tool.
Principled BSDF: Blender's name for the consolidated PBR shader. Most other apps ship the same shader under different names (Standard Surface, ShaderGraph, Substance). One node, every output.
process: How the material is MADE INTO the thing. The second entity. Cast, machined, kerf-bent, anodized, planished, granulated. Process is a peer of material, not a footnote.
quote: A voice block carrying a verbatim quotation from a living author, with citation. Distinct from a channeled block. Living = quote only; the rule is enforced at the schema layer.
roughness: Microsurface scatter. 0 is mirror-smooth; 1 is fully diffuse. Most real surfaces sit between 0.2 and 0.8.
sphere proxy: ForMatter's visible-character stand-in for every material. CSS-gradient driven by the entry's palette and finish, not a baked render. Honest about being a proxy, scales to six hundred entries cheaply, tweakable in one place.
substitute: A peer material that could fill a similar role. Cross-references render as sphere pills inside an entry — the gallery feeling extends inward.
transmission: How much light passes through. 1 is fully transparent; 0 is opaque. Glass, gemstones, clear plastics carry transmission.
PVD: Physical Vapor Deposition — vacuum-chamber sputter or cathodic-arc deposition of a thin ceramic film onto a metal substrate. The CMF-layer's modern coating chemistry: TiN (gold), ZrN (champagne), CrN (pewter), TiCN (warm bronze / rose-gold), AlTiN (charcoal-anthracite, near-black), DLC (deep black). Hard, doesn't tarnish, paint-thin.
VDI 3400: German engineering reference standard for mold-cavity texture (Erodieren bearbeitete Werkstückoberflächen). The full scale runs reference plates 0–45 by Ra value; production specs typically draw from 12–45 because plates 0–11 require diamond-mirror polish on the mold cavity and are rarely commissioned in commercial tooling. Pairs with the SPI standard; both define what gets cut into the mold.
voice block: A versal block where a real authored voice attaches to the material or process. Schema-tagged with status (living / dead) and mode (quote / channeled). Citations always.
woodgrain (finish): Directional sheen with grain ring. Drives PBR defaults: anisotropic 0.6, medium roughness, no metalness. Every wood entry.

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ForMatter

Materials and processes for people who design and make things.

A local-first library of materials, processes, applications, and finishes — equal weight, citable everywhere, with cost-over-volume curves, trade-off profiles, equipment-tier filters, and second-life paths layered onto the data so a student can move from "what is this" toward "what's actually buildable here, now, by me." Part of the renato.design ecosystem — sibling of Plenum, Specimen, Ingenue, gesture, graf, and the Renato Rhino plug-ins. Form and matter, inseparable.

Why this exists

Half of teaching materials is teaching how the material is made into the thing. The standard subscription library was always light on that half. The wedge here isn't better samples or a prettier interface — it's treating Process as a peer entity, not a footnote.

Rules of the house

Citations or it didn't happen. Every property number, every claim, every borrowed register has a traceable source.
Living authors are quoted only. Verbatim or not at all.
Dead authors may be channeled within their philosophy — marked, cited, never impersonated.
Permalink or nothing. Museum holdings link to the specific collection-record URL. Designer overview pages, press releases, and exhibition listings don't qualify.
Relative, not absolute. Cost, lead time, and other figures that age get published as ratios and ranges. Crossover points beat magnitudes.
Confidence labeled honestly. A senior's low-confidence-with-three-citations beats a freshman's high-confidence-with-none.
Local-first. Works offline, no login, no subscription.

Sister apps

Ingenue — five voices argue about what to build from electronic parts. Where ForMatter teaches what the thing is made of, Ingenue proposes what the thing could be.
Plenum — VIN, fender-tag, and broadcast-sheet decoder for muscle and pony cars; doo-wop register.
Specimen — iPhone 3D scanner that treats the captured object as a specimen, with voiced commentary.
renato.design — the rest.

Sources

Conway's Material World on raw materials, Lefteri's Making It on processes, Forty's Concrete and Culture, Sparke's Design in Context, Bürdek's Design: History, Theory and Practice of Product Design, Schröpfer's Material Design on materials in architecture, Winchester's The Perfectionists on tolerance, Minshall's Your Life Is Manufactured on the global supply chain, von Busch's Making Trouble on material activism, Were's How Materials Matter, Hegger / Drexler / Zeumer's Basics Materials, Untracht and McCreight on metalsmithing, USDA Forest Products Lab on woods, GIA on gemstones, Schott / CoorsTek / Toray / Owens Corning datasheets, MakeItFrom for verifiable property numbers, ASM Handbook, ISO standards. Museum holdings draw from the Met, MAD, V&A, Smithsonian American Art Museum, Newark Museum of Art, British Museum, Heard Museum, Smithsonian NMAI, Eiteljorg Museum, Philadelphia Museum of Art, Cranbrook Art Museum, and Grand Rapids Art Museum — collection-record permalinks only, designer overview pages and exhibition listings excluded. Voice blocks now ride on every entry kind — material, process, application, and finish — and include Ruskin on iron, Anni Albers on twining, Greg Lynn on the shred-and-teeth NURBS lineage, Pugin on the metal that won't be hammered, Barthes / Yanagi / Benjamin channeled within their philosophy; Sparke, Bürdek, Forty, Conway, Schröpfer, Minshall, von Busch, Lefteri, Pat Pruitt, Mary Lee Hu, Tom Joyce, Albert Paley, and the rest of the contemporary makers quoted verbatim with citation. All cited.

v0.6.82 — 2026-05-11 · Phil Renato · renato.design · MIT-licensed code, CC BY-NC research content