{"$schema":"nativecad-dfm-pack/1","id":"automotive","title":"Automotive — brackets, sheet-metal body/structure, die-cast and trim, EV and underhood","sector":"automotive","version":"2026-09-03","summary":"Bracket and mount fastener conventions, body/structure sheet-metal gauges, die-cast aluminium and injection-moulded trim rules, underhood thermal and vibration environment, EV battery enclosure and busbar basics, exhaust tube sizing, tolerancing and the salt-spray/thermal/vibration/flammability tests a vehicle part is held to.","aliases":["car","automotive bracket","vehicle","ev","battery enclosure","underhood","trim","body panel","exhaust","engine mount","engine","v12","crankcase ventilation","pcv","breather","oil drain"],"crossSector":false,"size":"full","sources":[{"id":"iso-16750-3","title":"ISO 16750-3:2023 Road vehicles — Environmental conditions — Part 3: Mechanical loads","url":"https://www.iso.org/standard/78026.html","accessed":"2026-09-03"},{"id":"iso-16750-4","title":"ISO 16750-4:2023 Road vehicles — Environmental conditions — Part 4: Climatic loads","url":"https://www.iso.org/standard/81219.html","accessed":"2026-09-03"},{"id":"astm-b117","title":"ASTM B117-19 Standard Practice for Operating Salt Spray (Fog) Apparatus","url":"https://www.astm.org/b0117-19.html","accessed":"2026-09-03"},{"id":"fmvss-302","title":"FMVSS 302 / 49 CFR 571.302 Flammability of Interior Materials","url":"https://www.ecfr.gov/current/title-49/subtitle-B/chapter-V/part-571/subpart-B/section-571.302","accessed":"2026-09-03"},{"id":"sae-j1455","title":"SAE J1455 Recommended Environmental Practices for Electronic Equipment Design (heavy-duty vehicle)","url":"https://www.sae.org/standards/content/j1455_202307/","accessed":"2026-09-03"},{"id":"gmw3172","title":"GMW3172 General Specification for Environmental/Durability Validation (GM worldwide standard)","accessed":"2026-09-03"},{"id":"nadca-403","title":"NADCA Product Specification Standards for Die Castings (draft, wall, tolerance)","url":"https://www.diecasting.org/","accessed":"2026-09-03"},{"id":"astm-a1011","title":"ASTM A1011/A1011M Standard Specification for Steel, Sheet and Strip, HSLA","url":"https://www.astm.org/a1011_a1011m-18a.html","accessed":"2026-09-03"},{"id":"sae-j2340","title":"SAE J2340 Categorization and Properties of Dent Resistant, High Strength, and Ultra-High Strength Automotive Sheet Steel","url":"https://www.sae.org/standards/content/j2340_202007/","accessed":"2026-09-03"},{"id":"sae-j2334","title":"SAE J2334 Laboratory Cyclic Corrosion Test","url":"https://www.sae.org/standards/content/j2334_201609/","accessed":"2026-09-03"},{"id":"iso-20653","title":"ISO 20653:2013 Road vehicles — Degrees of protection (IP code) — Protection of electrical equipment","url":"https://www.iso.org/standard/71681.html","accessed":"2026-09-03"},{"id":"iec-60529","title":"IEC 60529:1989+AMD2:2013 Degrees of protection provided by enclosures (IP Code)","url":"https://webstore.iec.ch/publication/2452","accessed":"2026-09-03"},{"id":"astm-a249","title":"ASTM A249/A249M Standard Specification for Welded Austenitic Steel Boiler, Superheater, Heat-Exchanger, and Condenser Tubes","url":"https://www.astm.org/a0249_a0249m-18.html","accessed":"2026-09-03"},{"id":"ford-fltm-bi123","title":"Ford FLTM BI 123-01 Laboratory Cyclic Corrosion Test","accessed":"2026-09-03"},{"id":"sae-j2380","title":"SAE J2380 Vibration Testing of Electric Vehicle Battery Systems","url":"https://www.sae.org/standards/content/j2380_201310/","accessed":"2026-09-03"},{"id":"sae-j20","title":"SAE J20 Coolant System Hoses","url":"https://www.sae.org/standards/content/j20/","accessed":"2026-09-14"},{"id":"nativecad-v12-showcase","title":"NativeCAD V12 engine showcase — ventilation, drain-back and feed plumbing rebuilt as audited flow paths (CADSB-908/914/917)","url":"https://featureboard.ai/nativecad/web/v12-engine.html","accessed":"2026-09-14"}],"entries":[{"id":"bolt-class-usage-8-8-10-9","kind":"fastener","tier":1,"title":"Bracket and mount bolt class: M6/M8/M10, 8.8 vs 10.9","summary":"Chassis and bracket bolts run M6, M8 and M10 mostly in property class 8.8; 10.9 is used where the joint is fatigue- or shear-critical (engine mounts, suspension brackets) — never mix a 10.9 bolt with an 8.8 nut.","applies":["bracket","mount","chassis fastener"],"value":{"options":["M6 class 8.8","M8 class 8.8","M10 class 8.8","M8 class 10.9","M10 class 10.9"]},"basis":"ISO 898-1 property classes; 10.9 reserved for fatigue-critical joints per common OEM fastener standards","sources":["sae-j2340"],"see":["hardware/bolt-torque-and-preload-classes","hardware/torque-table-class-8-8"],"tags":["bolt","class","bracket","mount","8.8","10.9"]},{"id":"weld-nut-sizing","kind":"fastener","tier":1,"title":"Weld nut sizes for body-in-white attachment","summary":"Square and hex weld nuts for body brackets run M5–M10, projection-welded to 0.7–2.0 mm panel; pilot hole is the nut's tapped size plus 0.5–1.0 mm to seat the weld projections without arc blow.","applies":["weld nut","body-in-white","bracket attachment"],"value":{"options":["M5","M6","M8","M10"]},"basis":"Common OEM weld-nut standards (e.g. GM/Ford weld-fastener specs) size the pilot to the projection ring, not the thread","sources":["gmw3172"],"tags":["weld-nut","projection-weld","body-in-white"]},{"id":"clip-christmas-tree-holes","kind":"fastener","tier":1,"title":"Clip and christmas-tree fastener hole sizes","summary":"Christmas-tree (arrowhead) push clips take a ⌀6.3 mm or ⌀8 mm panel hole in 0.7–3 mm sheet or trim; ⌀6.3 mm is the common 2-leg clip, ⌀8 mm the heavier 4-leg / high-retention clip.","applies":["trim clip","christmas tree clip","panel fastener"],"value":{"options":["6.3 mm hole","8 mm hole"]},"basis":"Trim-clip vendor catalogs (ITW, Nifco, Bollhoff) standardise on these two panel-hole sizes across 0.7–3 mm stock","sources":["gmw3172"],"tags":["clip","christmas-tree","trim","hole"]},{"id":"push-pin-hole-sizes","kind":"fastener","tier":1,"title":"Push-pin (nylon dowel) fastener hole sizes","summary":"Nylon push-pin fasteners take ⌀6.5, ⌀7 or ⌀8 mm mating panel holes depending on pin family; the pin's flared shank interferes 0.2–0.5 mm past the hole to lock, so undersizing 0.1 mm below spec loses retention.","applies":["push pin","trim fastener","panel fastener"],"value":{"options":["6.5 mm hole","7 mm hole","8 mm hole"]},"basis":"Common trim push-pin catalog hole callouts (e.g. Ford/GM interior trim fastener specs)","sources":["gmw3172"],"tags":["push-pin","trim","hole","nylon"]},{"id":"u-nut-j-nut-panel-thickness","kind":"fastener","tier":1,"title":"U-nut / J-nut spring clip panel thickness range","summary":"U-nuts and J-nuts (spring steel push-on nuts) clamp onto 0.6–2.5 mm flange panels; select by flange thickness first, then by the screw's major diameter (commonly M5–M6 for trim, M6–M8 for structural clips).","applies":["u-nut","j-nut","spring clip nut"],"value":{"min":0.6,"max":2.5,"unit":"mm"},"basis":"Spring-clip nut catalogs size the leg spread to a flange-thickness range, independent of thread size","sources":["gmw3172"],"tags":["u-nut","j-nut","clip-nut","flange"]},{"id":"body-panel-gauge-outer","kind":"dimension","tier":1,"title":"Outer body panel gauge (skin panels)","summary":"Exterior skin panels (doors, fenders, hood, roof) run 0.7–0.8 mm cold-rolled or HSLA steel, or 0.8–1.0 mm for aluminium skins, to hold class-A surface with minimum mass.","applies":["body panel","skin panel","outer panel"],"value":{"min":0.7,"max":0.8,"unit":"mm"},"basis":"Dent-resistance vs. mass trade-off standardised across OEM body-panel gauge tables","sources":["sae-j2340","astm-a1011"],"tags":["body-panel","gauge","skin","outer"]},{"id":"bracket-sheet-gauge","kind":"dimension","tier":1,"title":"Bracket sheet-metal gauge","summary":"Formed steel brackets (mounting brackets, reinforcements, small load-carrying stampings) run 1.0–2.0 mm, chosen by the fastener class and the bracket's span rather than by panel-class rules.","applies":["bracket","reinforcement","stamped bracket"],"value":{"min":1,"max":2,"unit":"mm"},"basis":"Typical OEM bracket-gauge tables for M6–M10 fastener classes on cantilevered brackets","sources":["astm-a1011"],"tags":["bracket","gauge","sheet-metal"]},{"id":"structural-sheet-gauge","kind":"dimension","tier":1,"title":"Structural sheet-metal gauge (rails, crossmembers, load paths)","summary":"Structural stampings that carry crash or chassis load (rails, crossmembers, pillar reinforcements) run 2.0–3.0 mm HSLA/DP steel, thicker where a hot-stamped boron grade is not used.","applies":["structural member","rail","crossmember","pillar reinforcement"],"value":{"min":2,"max":3,"unit":"mm"},"basis":"Load-path stampings need section modulus that 2.0 mm and below cannot give without a hot-stamped grade","sources":["astm-a1011","sae-j2340"],"tags":["structural","gauge","hsla","dp-steel"]},{"id":"hole-to-edge-bend-automotive","kind":"rule","tier":1,"title":"Hole-to-edge and hole-to-bend distance on automotive stampings","summary":"Keep a hole centre >= 2x its diameter from a cut edge and >= 2.5x the material thickness plus the bend radius from a bend line, or the flange tears or the hole distorts during forming.","applies":["bracket","body panel","stamped part"],"basis":"General sheet-metal tearing/distortion limits near a bend, tighter than the generic edge-distance rule because of springback","sources":["astm-a1011"],"see":["hardware/edge-distance-holes"],"check":{"process":"sheet-metal","rule":"hole-to-bend-distance"},"tags":["hole","edge-distance","bend","stamping"]},{"id":"diecast-a380-wall-thickness","kind":"process","tier":1,"title":"Die-cast aluminium (A380) nominal wall thickness","summary":"A380 high-pressure die-cast walls run 2–4 mm nominal; below 2 mm the die fills unreliably, above 4 mm the section develops shrink porosity and extends cycle time.","applies":["die-cast bracket","housing","A380 casting"],"value":{"min":2,"max":4,"unit":"mm"},"basis":"NADCA process-capability wall-thickness guidance for A380 HPDC","sources":["nadca-403"],"check":{"process":"die-casting","rule":"min-wall"},"tags":["die-cast","a380","wall-thickness"]},{"id":"diecast-draft-angle","kind":"rule","tier":1,"title":"Die-cast draft angle","summary":"A380 die-cast exterior walls need 1-2 deg of draft per side to release from the die without galling; textured or deep-cavity walls want the higher end.","applies":["die-cast bracket","housing","A380 casting"],"value":{"min":1,"max":2,"unit":"deg"},"basis":"NADCA draft-angle recommendation for aluminium HPDC","sources":["nadca-403"],"check":{"process":"die-casting","rule":"min-draft"},"tags":["die-cast","draft","a380"]},{"id":"diecast-rib-thickness-ratio","kind":"rule","tier":1,"title":"Die-cast rib thickness vs. wall","summary":"Ribs on an A380 casting should stay at or below 60% of the adjacent wall thickness to avoid sink marks on the show surface opposite the rib.","applies":["die-cast bracket","housing","A380 casting"],"value":{"typical":60,"unit":"%"},"basis":"Cooling-rate mismatch at a rib-to-wall junction thicker than 60% pulls the opposite face in as it solidifies","sources":["nadca-403"],"check":{"process":"die-casting","rule":"rib-to-wall-ratio"},"tags":["die-cast","rib","sink-mark"]},{"id":"trim-wall-thickness-pp-tpo","kind":"dimension","tier":1,"title":"Injection-moulded trim wall thickness (PP/TPO)","summary":"Interior and exterior trim panels in PP or TPO mould at 2.5–3.5 mm nominal wall; thinner sections risk short shots across a large flow length, thicker sections add sink and cycle time.","applies":["trim panel","interior trim","PP trim","TPO trim"],"value":{"min":2.5,"max":3.5,"unit":"mm"},"basis":"PP/TPO flow-length-to-wall ratio at typical trim-panel flow lengths (300-800 mm)","sources":["sae-j1455"],"check":{"process":"injection-molding","rule":"min-wall"},"tags":["trim","pp","tpo","wall-thickness"]},{"id":"trim-draft-angle","kind":"rule","tier":1,"title":"Trim panel draft angle, plus grain allowance","summary":"PP/TPO trim walls need >= 1 deg draft per side to eject cleanly; add roughly +1 deg of draft per 0.025 mm of texture/grain depth so a grained panel with 0.075 mm texture wants about 4 deg.","applies":["trim panel","grained trim","textured trim"],"value":{"min":1,"unit":"deg"},"basis":"Standard injection-mould grain-draft allowance (mold-tech style guidance): +1 deg per 0.025 mm texture depth","sources":["sae-j1455"],"check":{"process":"injection-molding","rule":"min-draft"},"tags":["trim","draft","grain","texture"]},{"id":"underhood-temp-zones","kind":"dimension","tier":1,"title":"Underhood ambient temperature by mounting zone","summary":"Underhood component ambient runs 105 C for engine-bay-general locations, up to 125 C near the exhaust manifold shield, and up to 150 C for parts clamped directly to the engine block or turbo heat shield.","applies":["underhood component","bracket","connector","sensor housing"],"value":{"min":105,"max":150,"unit":"C"},"basis":"ISO 16750-4 climatic-load temperature classes by mounting location","sources":["iso-16750-4"],"tags":["underhood","temperature","thermal-zone"]},{"id":"bracket-first-mode-rule","kind":"rule","tier":1,"title":"Bracket first natural frequency > 200 Hz","summary":"A vehicle bracket should keep its first bending mode above 200 Hz so it does not resonate with the engine's firing-order excitation band or road-induced random vibration below that frequency.","applies":["bracket","mount","sensor bracket"],"value":{"min":200,"unit":"Hz"},"basis":"Keeps the bracket's fundamental clear of typical 4-cylinder firing-order and chassis random-vibration content (10-200 Hz band)","sources":["iso-16750-3"],"tags":["vibration","natural-frequency","bracket","nvh"]},{"id":"biw-tolerance-rps","kind":"tolerance","tier":1,"title":"Body-in-white tolerance under an RPS / 3-2-1 datum scheme","summary":"Body-in-white sheet-metal assemblies hold approximately +/-0.5 mm at the reference point system (RPS) locators; feature-to-feature tolerance on a single stamping is typically +/-0.3-0.5 mm.","applies":["body-in-white","stamping","assembly"],"value":{"typical":0.5,"unit":"mm"},"basis":"Standard OEM RPS tolerance stack-up target for BIW sub-assembly build","sources":["gmw3172"],"tags":["tolerance","rps","biw","3-2-1"]},{"id":"machined-tolerance-automotive","kind":"tolerance","tier":1,"title":"Machined automotive component tolerance","summary":"Machined automotive features (bearing bores, mount faces, bolt patterns) hold +/-0.1 to +/-0.2 mm general tolerance, tightening to +/-0.02-0.05 mm on bearing fits and sealing faces.","applies":["machined bracket","housing","mount face"],"value":{"min":0.1,"max":0.2,"unit":"mm"},"basis":"Typical OEM machining general-tolerance class for cast/machined automotive components","sources":["nadca-403"],"tags":["tolerance","machining","bore","mount-face"]},{"id":"three-two-one-datum-scheme","kind":"feature","tier":2,"title":"3-2-1 / RPS datum scheme for body and bracket fixturing","summary":"Locate a body panel or bracket on 6 points: 3 removing Z-rotation and tip/tilt on the primary plane, 2 removing in-plane rotation on a secondary edge, 1 removing the last in-plane DOF on a locator hole, per the RPS convention.","applies":["body-in-white","bracket","fixture design"],"basis":"Reference point system (RPS) is the standard automotive 3-2-1 fixturing convention for repeatable measurement and build","sources":["gmw3172"],"tags":["rps","3-2-1","datum","fixturing"]},{"id":"battery-enclosure-ip67","kind":"rule","tier":1,"title":"EV battery enclosure sealing target: IP67","summary":"An EV battery pack enclosure seals to IP67 (dust-tight, 1 m submersion for 30 min) at minimum, using a compressed EPDM or silicone gasket at the lid-to-tray joint with continuous bolt-and-groove compression.","applies":["battery enclosure","battery tray","ev pack"],"value":{"value":"IP67","unit":"text"},"basis":"ISO 20653 / IEC 60529 IP67 is the common minimum EV pack sealing target across OEM specs","sources":["iso-20653","iec-60529"],"tags":["ev","battery-enclosure","ip67","sealing"]},{"id":"busbar-clearance-creepage","kind":"dimension","tier":2,"title":"Busbar clearance and creepage by system voltage (400 V / 800 V)","summary":"At 400 V a busbar wants roughly 5-8 mm air clearance and 8-12 mm creepage to the next live part or ground; at 800 V that roughly doubles to 10-14 mm clearance and 16-20 mm creepage, per pollution degree and material group.","applies":["busbar","hv connector","battery pack","inverter"],"value":{"table":[{"voltage_v":400,"clearance_mm":"5-8","creepage_mm":"8-12"},{"voltage_v":800,"clearance_mm":"10-14","creepage_mm":"16-20"}]},"basis":"IEC 60664-1 style pollution-degree-2 clearance/creepage scaling as applied by EV HV harness and busbar guides","sources":["iso-20653"],"tags":["ev","busbar","clearance","creepage","400v","800v"]},{"id":"exhaust-tube-stainless-dims","kind":"dimension","tier":2,"title":"Exhaust tube diameter and wall (409/304 stainless)","summary":"Exhaust tube runs 45-76 mm outer diameter by 1.2-1.5 mm wall in 409 stainless for cost-driven mid/rear sections, or 304 stainless nearer the manifold for better heat and corrosion resistance.","applies":["exhaust pipe","exhaust tube","muffler inlet"],"value":{"min":45,"max":76,"unit":"mm"},"basis":"Common OEM exhaust-tube size range for 4-6 cylinder passenger-vehicle exhaust systems","sources":["astm-a249"],"tags":["exhaust","stainless","409","304","tube"]},{"id":"engine-mount-rubber-durometer","kind":"material","tier":2,"title":"Engine mount rubber durometer","summary":"Engine and powertrain mount rubber (natural rubber or EPDM blend) runs 40-70 Shore A; softer compounds isolate idle vibration better, stiffer compounds control powertrain roll under torque.","applies":["engine mount","powertrain mount","rubber isolator"],"value":{"options":["40 Shore A","50 Shore A","60 Shore A","70 Shore A"]},"basis":"Typical OEM engine-mount elastomer durometer range trading isolation against roll stiffness","sources":["iso-16750-3"],"tags":["engine-mount","rubber","durometer","epdm"]},{"id":"cell-module-sizes-ev","kind":"dimension","tier":2,"title":"EV cell and module envelope sizes (2170 / 4680 / prismatic)","summary":"Cylindrical EV cells are 21 mm dia x 70 mm (2170) or 46 mm dia x 80 mm (4680); prismatic cells commonly run 100-150 mm wide x 30-50 mm thick x 90-200 mm tall, packed into modules with 0.5-1.5 mm compression pad gaps.","applies":["battery cell","battery module","ev pack"],"value":{"options":["2170 (21x70 mm)","4680 (46x80 mm)","prismatic 100-150x30-50x90-200 mm"]},"basis":"Published cylindrical-cell form factors and typical prismatic-cell envelope ranges used in EV pack layout","sources":["sae-j2380"],"tags":["ev","cell","module","2170","4680","prismatic"]},{"id":"random-vibration-psd-typical","kind":"dimension","tier":2,"title":"Random vibration test PSD, 10-1000 Hz (automotive component)","summary":"A typical automotive random-vibration profile spans 10-1000 Hz with a flat PSD around 0.01-0.04 g2/Hz through the mid-band, giving roughly 3-7 g RMS overall depending on mounting location.","applies":["bracket","sensor","ecu","underhood component"],"value":{"table":[{"band_hz":"10-50","level":"rising slope"},{"band_hz":"50-500","level":"0.01-0.04 g2/Hz flat"},{"band_hz":"500-1000","level":"falling slope"}]},"basis":"ISO 16750-3 random-vibration severity classes for engine-mounted vs. body-mounted locations","sources":["iso-16750-3"],"check":{"process":"vibration","rule":"random-psd-envelope"},"tags":["vibration","psd","random","10-1000hz"]},{"id":"mechanical-shock-20g","kind":"rule","tier":1,"title":"Mechanical shock pulse: 20 g automotive component","summary":"Automotive brackets and enclosures should survive a 20 g, 6-11 ms half-sine mechanical shock pulse without fracture or fastener loosening, applied in each of 3 axes.","applies":["bracket","ecu housing","connector"],"value":{"typical":20,"unit":"g"},"basis":"ISO 16750-3 mechanical shock test severity for chassis- and body-mounted components","sources":["iso-16750-3"],"tags":["shock","20g","mechanical-load"]},{"id":"hsla-dp-steel-automotive","kind":"material","tier":2,"title":"HSLA and dual-phase (DP) steel for automotive structure","summary":"HSLA steel (yield 350-550 MPa) and dual-phase DP steel (tensile 590-980 MPa) are the default for structural stampings, offering more strength per mm than mild steel so gauge can drop while keeping crash performance.","applies":["structural stamping","rail","crossmember","reinforcement"],"value":{"min":350,"max":980,"unit":"MPa"},"basis":"SAE J2340 categorises automotive sheet steel grades by yield/tensile band for structural design","sources":["sae-j2340","astm-a1011"],"detail":"HSLA grades (SAE J2340 classes like 350Y or 500Y) trade formability for yield strength and are the workhorse for brackets and moderate-load structure. DP steel achieves higher tensile strength (DP590 through DP980) via a martensite-in-ferrite microstructure, giving good work hardening for crash-energy-absorbing rails and pillars at thinner gauge than HSLA would need for the same energy absorption. Both weld with standard resistance spot-welding schedules used elsewhere in the body shop, though DP980 needs tighter current control to avoid expulsion. Selecting between them is a stiffness-vs-formability call: HSLA bends more readily for deep-drawn brackets, DP is preferred where crash-energy management dominates the design.","tags":["hsla","dp-steel","structural","material"]},{"id":"al-6xxx-automotive-brackets","kind":"material","tier":2,"title":"6061/6082 aluminium for machined and extruded brackets","summary":"6061-T6 and 6082-T6 aluminium (yield ~ 240-260 MPa) are used for machined or extruded brackets and crash structure where mass matters more than the cost premium over steel.","applies":["machined bracket","extruded crash rail","aluminium bracket"],"value":{"min":240,"max":260,"unit":"MPa"},"basis":"6061-T6/6082-T6 yield strength and machinability make them the default automotive aluminium alloys outside die casting","sources":["nadca-403"],"see":["materials/al-6061-t6"],"detail":"6061-T6 is the more commonly stocked and more machinable of the two, preferred for CNC brackets and adapter plates. 6082-T6 has slightly higher strength and is favoured in Europe for extruded structural sections (crash rails, battery tray frames) because its extrusion behaviour and weldability are well characterised for that use. Both anodize well for corrosion protection on exposed brackets, and both need a bimetallic isolation (paint, tape, or a plastic washer) where they contact steel to avoid galvanic corrosion in a wet underbody environment.","tags":["6061","6082","aluminium","bracket","extrusion"]},{"id":"a380-alloy-properties","kind":"material","tier":2,"title":"A380 die-cast aluminium alloy properties","summary":"A380 (Al-Si8.5Cu3.5) is the default high-pressure die-cast alloy for automotive housings and brackets: ultimate tensile ~ 320 MPa, elongation ~ 3.5%, good fluidity for thin-wall filling.","applies":["die-cast housing","die-cast bracket","transmission case"],"value":{"typical":320,"unit":"MPa"},"basis":"Standard A380 (ADC12-equivalent) as-cast mechanical property sheet used across die-casting suppliers","sources":["nadca-403"],"detail":"A380's silicon content gives it excellent die-fill characteristics at the 2-4 mm walls typical of automotive HPDC housings, and its copper content raises strength at some cost to corrosion resistance versus a copper-free alloy like A413. Elongation of roughly 3.5% means A380 parts are not meant to flex in service — brackets should be sized so working stress stays well below the ~320 MPa UTS with margin for the porosity any die casting carries. It is not weldable by conventional fusion welding due to trapped gas porosity; mechanical fastening or adhesive bonding is used to join A380 castings to other structure.","tags":["a380","die-cast","aluminium","material"]},{"id":"pa66-gf30-underhood","kind":"material","tier":2,"title":"PA66-GF30 for underhood connectors and brackets","summary":"Glass-filled nylon PA66-GF30 (30% glass) is the default for underhood connector housings and small brackets: tensile strength ~ 180 MPa, heat deflection ~ 250 C, good chemical resistance to oil and coolant splash.","applies":["underhood connector","underhood bracket","sensor housing"],"value":{"typical":180,"unit":"MPa"},"basis":"PA66-GF30 datasheet range as widely used across automotive underhood connector and bracket suppliers","sources":["sae-j1455"],"detail":"The 30% glass loading roughly doubles tensile strength and stiffness over unfilled PA66 while raising heat deflection temperature well above the 105-150 C underhood zone range, which is why it is the default over unfilled nylon for anything clamped near the engine or exhaust. PA66 is hygroscopic, so dimensions and impact strength shift with moisture absorption; parts with tight fits (connector latches, gear teeth) are often designed and toleranced at a specified conditioned-moisture state rather than bone-dry. It resists motor oil, coolant and short splash exposure to fuel but is attacked by strong acids, which rules it out for battery-acid-adjacent locations.","tags":["pa66","gf30","nylon","underhood","connector"]},{"id":"pp-td20-trim","kind":"material","tier":2,"title":"PP-TD20 (talc-filled polypropylene) for interior trim","summary":"Talc-filled polypropylene PP-TD20 (20% talc) is the workhorse interior trim resin: tensile strength ~ 25-30 MPa, low cost, low warp, and takes grain texture and paint or in-mould colour well.","applies":["interior trim","door panel","trim bracket"],"value":{"min":25,"max":30,"unit":"MPa"},"basis":"PP-TD20 datasheet property range as commonly specified for automotive interior trim panels","sources":["sae-j1455"],"detail":"Talc filling stiffens PP and reduces its mould shrinkage relative to unfilled PP, which is why PP-TD20 (or PP-TD10/PP-TD40 variants at other loadings) holds flatness better across the 2.5-3.5 mm trim wall than unfilled homopolymer PP would at the same gauge. It is a lower-cost alternative to TPO or PC/ABS blends for panels that do not need TPO's better low-temperature impact resistance or PC/ABS's higher heat resistance, and it recycles more simply than blended resins, which is a factor in interior trim material selection under OEM recyclability targets.","tags":["pp","td20","talc","trim","interior"]},{"id":"epdm-seals-mounts","kind":"material","tier":2,"title":"EPDM for weatherseals, grommets and mount isolators","summary":"EPDM rubber is the default for weatherstrip, grommets and vibration-isolation bushings exposed to weather: durometer 40-80 Shore A, good ozone and UV resistance, poor resistance to petroleum oils.","applies":["weatherseal","grommet","isolator bushing","battery enclosure gasket"],"value":{"options":["40 Shore A","60 Shore A","80 Shore A"]},"basis":"EPDM's ozone/UV/weathering resistance is why it, not nitrile or neoprene, is the default automotive exterior seal elastomer","sources":["iso-16750-4"],"detail":"EPDM's saturated backbone gives it strong resistance to ozone cracking and UV degradation, which is essential for door and body weatherseals that live outdoors for the vehicle's life, and it stays flexible across a wide temperature range relevant to ISO 16750-4 climatic classes. Its weakness is petroleum-based fluids: EPDM swells and softens in engine oil, fuel and many greases, so it is not used for underhood fluid-line seals (those use fluoroelastomer or nitrile instead) even though it is the right choice for a battery-enclosure lid gasket or a door seal that never sees oil.","tags":["epdm","seal","grommet","isolator","weatherstrip"]},{"id":"salt-spray-astm-b117","kind":"test","tier":2,"title":"Salt spray corrosion test (ASTM B117), 96-480 h","summary":"ASTM B117 neutral salt-fog exposure runs 96 h for a mild corrosion-class fastener or bracket up to 480 h or more for a structural or exposed underbody part; the geometry rule is no crevice or unsealed lap joint that traps salt fog.","applies":["bracket","fastener","underbody part","exposed hardware"],"value":{"min":96,"max":480,"unit":"h"},"basis":"ASTM B117 duration classes scale with the part's corrosion-protection requirement and exposure zone","sources":["astm-b117"],"tags":["test","salt-spray","corrosion","astm-b117"]},{"id":"thermal-shock-cycling-underhood","kind":"test","tier":2,"title":"Thermal shock / thermal cycling test, -40 to +125 C","summary":"Underhood components cycle between -40 C and +125 C (some zones to +150 C) with dwell and short transfer time between chambers, for hundreds to a few thousand cycles; the geometry rule is no trapped-moisture cavity and matched CTE at bonded or press-fit interfaces.","applies":["underhood connector","sensor housing","bracket assembly"],"value":{"min":-40,"max":125,"unit":"C"},"basis":"ISO 16750-4 thermal shock/cycling severity classes for underhood-mounted electrical and mechanical parts","sources":["iso-16750-4"],"tags":["test","thermal-shock","thermal-cycling","underhood"]},{"id":"iso16750-vibration-mechanical-test","kind":"test","tier":2,"title":"ISO 16750 vibration and mechanical load test","summary":"ISO 16750-3 combines a 10-1000 Hz random vibration sweep (hours per axis, by mounting-location severity class) with the 20 g mechanical shock pulse; the geometry rule is every bracket clears its first-mode-above-200-Hz target before this test is run.","applies":["bracket","ecu","sensor","connector assembly"],"basis":"ISO 16750-3 is the harmonised automotive mechanical-environment test most OEM component specs point to","sources":["iso-16750-3"],"tags":["test","iso-16750","vibration","mechanical-shock"]},{"id":"fmvss302-flammability-test","kind":"test","tier":2,"title":"FMVSS 302 interior flammability test","summary":"FMVSS 302 requires interior trim materials within reach of an occupant to burn no faster than 102 mm/min horizontally, or self-extinguish; the geometry rule is no unsupported thin edge of trim material left as an ignition-prone free edge.","applies":["interior trim","seat trim","headliner","door panel"],"value":{"value":"102 mm/min"},"basis":"FMVSS 302 / 49 CFR 571.302 burn-rate limit for occupant-compartment materials","sources":["fmvss-302"],"tags":["test","fmvss302","flammability","interior"]},{"id":"iso-16750-standard-family","kind":"standard","tier":2,"title":"ISO 16750 series: road vehicle environmental conditions","summary":"ISO 16750 (parts 1-5) sets electrical, mechanical, climatic, chemical and dust/water environmental test classes for road-vehicle electrical/electronic equipment; parts 3 and 4 are the ones with direct geometric implications (vibration, shock, thermal cycling).","applies":["ecu","sensor","connector","bracket assembly"],"basis":"The umbrella series most OEM component specifications reference for environmental qualification","sources":["iso-16750-3","iso-16750-4"],"tags":["standard","iso-16750","environmental"]},{"id":"gmw-ford-standard-families","kind":"standard","tier":2,"title":"GMW and Ford (WSS/FLTM) engineering standard families","summary":"GM's GMW-series (e.g. GMW3172 durability/environmental validation) and Ford's WSS material specs plus FLTM lab test methods (e.g. FLTM BI 123-01 cyclic corrosion) are the two dominant US OEM in-house standard families a supplier drawing will cite.","applies":["bracket","fastener","trim","sheet-metal part"],"basis":"Both OEMs maintain their own validation and material-spec numbering independent of ISO/SAE, and supplier drawings routinely call them out directly","sources":["gmw3172","ford-fltm-bi123"],"tags":["standard","gmw","ford","wss","fltm"]},{"id":"rivet-nut-automotive","kind":"fastener","tier":2,"title":"Rivet nuts (rivnuts) for blind-side bracket attachment","summary":"Rivet nuts (M5-M10) attach a threaded boss to sheet metal from one side, used where the backside is inaccessible (sealed box sections, closed panels); install hole is the rivnut body diameter plus 0.1-0.2 mm clearance.","applies":["blind fastener","bracket attachment","closed section"],"value":{"options":["M5","M6","M8","M10"]},"basis":"Standard rivnut sizing for one-sided access on automotive closed sections","sources":["gmw3172"],"see":["hardware/rivnut-hole-sizes"],"tags":["rivnut","blind-fastener","sheet-metal"]},{"id":"weld-stud-projection","kind":"fastener","tier":2,"title":"Projection-welded studs for trim and harness attachment","summary":"Threaded weld studs (M5-M8) are projection-welded to 0.7-2.0 mm panel for attaching trim clips, ground straps or harness brackets; stud base diameter needs >= 3x panel thickness of flat panel around it for a sound weld nugget.","applies":["weld stud","ground stud","harness bracket"],"value":{"options":["M5","M6","M8"]},"basis":"Resistance-projection-welding process guidance for stud attachment on body-panel gauges","sources":["gmw3172"],"tags":["weld-stud","projection-weld","ground-strap"]},{"id":"corrosion-protection-coating","kind":"process","tier":2,"title":"E-coat and zinc-phosphate corrosion protection stack","summary":"Body-in-white steel gets a zinc-phosphate pretreatment plus 18-25 um cathodic e-coat before assembly; brackets and fasteners exposed underbody add a zinc or zinc-nickel plating (5-12 um) for salt-spray life beyond bare e-coat.","applies":["body-in-white","bracket","fastener","underbody part"],"value":{"min":18,"max":25,"unit":"um"},"basis":"Standard OEM e-coat film-build specification for cathodic electrodeposition primer","sources":["sae-j2334"],"tags":["e-coat","zinc-phosphate","plating","corrosion"]},{"id":"underhood-connector-sealing","kind":"dimension","tier":2,"title":"Underhood connector sealing rating (IP6K9K)","summary":"Underhood electrical connectors typically seal to IP6K9K (dust-tight, high-pressure/steam-jet washdown resistant), tighter than the IP67 used for cabin or trunk-mounted connectors.","applies":["underhood connector","sensor connector","harness connector"],"value":{"value":"IP6K9K","unit":"text"},"basis":"ISO 20653's 9K test (high-pressure, high-temperature jet washing) reflects underhood pressure-washer exposure in service","sources":["iso-20653"],"tags":["connector","sealing","ip6k9k","underhood"]},{"id":"exhaust-clamp-joint","kind":"feature","tier":2,"title":"Exhaust pipe clamp joint (band or v-band)","summary":"Exhaust tube sections join with a band clamp over a 15-25 mm overlap slip-fit (tube OD plus 0.5-1.0 mm) or a v-band flange joint for high-vibration locations near the manifold; overlap joints allow the thermal-expansion slip a welded joint cannot.","applies":["exhaust pipe","exhaust joint","muffler connection"],"value":{"min":15,"max":25,"unit":"mm"},"basis":"Standard exhaust-system slip-joint overlap range balancing seal integrity against thermal-expansion slip","sources":["astm-a249"],"tags":["exhaust","clamp","v-band","slip-joint"]},{"id":"sheet-metal-hem-flange","kind":"feature","tier":2,"title":"Hem flange on body panel edges","summary":"Body panel edges (door skins, hood, deck lid) hem over an inner panel with a 4-6 mm hem flange and an inside bend radius approximately equal to the panel thickness, closing out the raw edge and stiffening it.","applies":["body panel","door skin","hood","deck lid"],"value":{"min":4,"max":6,"unit":"mm"},"basis":"Standard hem-flange geometry for 0.7-0.8 mm outer body panels closing onto an inner panel","sources":["astm-a1011"],"check":{"process":"sheet-metal","rule":"hem-flange-length"},"tags":["hem","flange","body-panel","edge"]},{"id":"clip-tower-plastic-trim","kind":"feature","tier":2,"title":"Clip boss / tower on injection-moulded trim","summary":"A trim clip tower is a cylindrical boss 6-10 mm diameter rising 8-15 mm from the trim wall, wall-thickness of the boss kept at 50-60% of the panel wall to avoid sink, with a thread-forming screw pilot hole through its centre.","applies":["trim panel","clip boss","screw boss"],"value":{"min":6,"max":10,"unit":"mm"},"basis":"Standard plastic screw-boss sink-avoidance ratio applied to trim-panel clip towers","sources":["sae-j1455"],"see":["hardware/screw-boss-plastic"],"tags":["clip-tower","boss","trim","screw-boss"]},{"id":"alternator-bracket-hole-pattern","kind":"dimension","tier":2,"title":"Alternator/accessory bracket mounting hole pattern","summary":"Accessory brackets (alternator, A/C compressor, power-steering pump) typically use a pivot hole plus an adjustment slot roughly 20-25 mm long for belt tensioning, with 2-3 additional M8-M10 mounting holes on the block face.","applies":["alternator bracket","accessory bracket","belt tensioner bracket"],"value":{"min":20,"max":25,"unit":"mm"},"basis":"Common accessory-bracket layout convention: one pivot, one tension slot, remaining holes as fixed mounts","sources":["sae-j2340"],"tags":["alternator","bracket","slot","mounting-holes"]},{"id":"recipe-alternator-bracket","kind":"recipe","tier":2,"title":"Recipe: alternator accessory bracket plate with slot and holes","summary":"Build a 90x40x5 mm steel accessory bracket plate with a 24x9 mm belt-tension adjustment slot and two M6 clearance mounting holes plus one M8 pivot hole.","applies":["alternator bracket","accessory bracket"],"basis":"Combines bracket-sheet-gauge, alternator-bracket-hole-pattern and hole-to-edge-bend-automotive into one buildable plate","sources":["astm-a1011","sae-j2340"],"tags":["recipe","bracket","alternator"],"recipe":{"prompt":"Model a 90x40x5mm steel alternator bracket plate with a 24x9mm belt-tension slot and an M8 pivot hole plus two M6 mounting holes","steps":[{"tool":"cad_box","args":{"dx":90,"dy":40,"dz":5},"note":"bracket plate, 5mm per bracket-sheet-gauge"},{"tool":"cad_box","args":{"dx":24,"dy":9,"dz":5,"origin":[8,15.5,0]},"note":"slot cutting tool, 24x9mm belt-tension adjustment slot"},{"tool":"cad_boolean_subtract","args":{"of":"$0","tool":"$1"},"note":"cut the adjustment slot"},{"tool":"cad_drill_hole","args":{"of":"$2","type":"drill","diameter":9,"center":[75,20],"through":true},"note":"M8 pivot hole, ISO 273 medium clearance"},{"tool":"cad_drill_hole","args":{"of":"$3","type":"drill","diameter":6.6,"center":[45,8],"through":true},"note":"M6 mounting hole 1"},{"tool":"cad_drill_hole","args":{"of":"$4","type":"drill","diameter":6.6,"center":[45,32],"through":true},"note":"M6 mounting hole 2"}],"expect":{"volume":16259.79,"faceCount":16,"watertight":true,"note":"measured 2026-09-19: agrees with the kernel on the CADSF-1630 corpus sweep — volume inside the 0.5% band and faceCount exact"}}},{"id":"recipe-heat-shield-sheet-metal","kind":"recipe","tier":2,"title":"Recipe: exhaust/manifold heat shield as a folded sheet-metal panel","summary":"Build a 120x80 mm, 0.8 mm stainless heat-shield base with 15 mm flanges folded on two sides, plus two 6.5 mm push-pin mounting holes.","applies":["heat shield","exhaust shield","manifold shield"],"basis":"Combines body-panel-gauge-outer, push-pin-hole-sizes and the sheet-metal folded-box tool into one buildable shield","sources":["astm-a1011"],"tags":["recipe","heat-shield","sheet-metal"],"recipe":{"prompt":"Model a 120x80mm stainless heat shield, 0.8mm thick, with 15mm flanges on the north and south edges and two 6.5mm push-pin holes","steps":[{"tool":"cad_sheet_box","args":{"thickness":0.8,"base":{"length":120,"width":80},"flanges":{"n":{"height":15},"s":{"height":15}}},"note":"0.8mm base per body-panel-gauge-outer, two folded flanges for stiffness"},{"tool":"cad_drill_hole","args":{"of":"$0","type":"drill","diameter":6.5,"axis":[0,0,-1],"start":[15,15,0.8],"depth":0.8},"note":"push-pin hole 1, explicit axis/start since the folded base is not the only flat face"},{"tool":"cad_drill_hole","args":{"of":"$1","type":"drill","diameter":6.5,"axis":[0,0,-1],"start":[105,65,0.8],"depth":0.8},"note":"push-pin hole 2"}],"expect":{"volume":10868.82,"faceCount":18,"watertight":true,"note":"measured 2026-09-19: representation change, not geometry: pinned while the boolean published a TESSELLATED B-rep (one planar face per triangle) and it now publishes an analytic one — faceCount 654 -> 18, volume identical to 0.002%: an all-planar body has no chord deficit, so there is nothing for the volume to show"}}},{"id":"recipe-trim-clip-boss","kind":"recipe","tier":2,"title":"Recipe: trim panel with a clip boss / tower","summary":"Build a 60x40x20 mm shelled trim panel section (2.5 mm wall) with an 8x8x15 mm clip boss tower unioned onto the floor and a 2.6 mm screw pilot hole through the tower.","applies":["trim panel","clip tower","screw boss"],"basis":"Combines trim-wall-thickness-pp-tpo and clip-tower-plastic-trim; uses box+union for the boss per the shelled-box face-selector limitation","sources":["sae-j1455"],"tags":["recipe","trim","clip-tower","boss"],"recipe":{"prompt":"Model a 60x40x20mm trim panel section shelled to 2.5mm wall with an 8x8x15mm clip boss tower on the floor and a 2.6mm screw pilot hole through it","steps":[{"tool":"cad_box","args":{"dx":60,"dy":40,"dz":20},"note":"trim panel block"},{"tool":"cad_shell","args":{"of":"$0","thickness":2.5,"open":[{"normal":[0,0,1]}]},"note":"2.5mm wall per trim-wall-thickness-pp-tpo, open top"},{"tool":"cad_box","args":{"dx":8,"dy":8,"dz":17.5,"origin":[26,16,0]},"note":"clip boss tower box, embedded from the outer floor (z=0) through the 2.5mm floor and up into the cavity so it truly overlaps the shelled solid"},{"tool":"cad_boolean_union","args":{"of":"$1","tool":"$2"},"note":"union the boss onto the shelled panel instead of a face-selected pad"},{"tool":"cad_drill_hole","args":{"of":"$3","type":"drill","diameter":2.6,"axis":[0,0,-1],"start":[30,20,17.5],"depth":10},"note":"thread-forming screw pilot through the boss"}],"expect":{"volume":15218.02,"faceCount":20,"watertight":true,"note":"measured 2026-09-19: CADSF-1561 (cc1f38cb, 2026-09-15) gave a BLIND hole a 118° DRILL POINT: the flat floor became a cone on the Ø2.6x10 blind boss hole: +1 face, and the point removes a further 0.55 mm^3. Not a representation change and not a regression"}}},{"id":"crankcase-ventilation-routing","kind":"feature","tier":2,"title":"Crankcase ventilation: breather spigots, separator, PCV valve","summary":"Each cam cover carries a breather spigot (~Ø18, bore ~Ø13) over a baffle; one bank's hose runs to a spigot through the airbox wall, the other's to an oil separator on the plenum lid feeding a PCV valve through the lid -- every hose over a spigot, clamped.","applies":["engine","cam cover","pcv","breather","airbox"],"value":{"value":18,"unit":"mm","note":"breather spigot OD; bore 13; hose lap 8"},"basis":"V12 showcase CADSB-914 rebuild of CADSF-1478/1480's floating ventilation; SAE J20 hose practice","sources":["nativecad-v12-showcase","sae-j20"],"tags":["pcv","breather","ventilation","hose","spigot","engine"],"detail":"Rebuilt in the V12 showcase (CADSB-914) after CADSF-1478/1480 shipped hoses ending in air, a separator floating over the lid and six decorative vacuum hooks; declared as a gas path and audited with cad_assembly_flowpath."},{"id":"head-drain-back-tube","kind":"feature","tier":2,"title":"External head-to-crankcase oil drain-back tube","summary":"A ~Ø18 tube from a boss on the head's outboard flank down to a boss on the block flank, routed behind the last exhaust flange and outboard of its stud nuts, 18 mm bends, 4 mm laps into both bosses -- a tube standing off the head connected to nothing is the V12's CADSB-917 defect.","applies":["engine","cylinder head","oil drain","block"],"value":{"value":18,"unit":"mm","note":"tube OD; bosses r13 x 17, bore 9.3"},"basis":"V12 showcase CADSB-917","sources":["nativecad-v12-showcase"],"tags":["oil","drain","head","tube","engine"]},{"id":"external-head-oil-feed","kind":"feature","tier":2,"title":"External head oil feed: union, bend-radius first leg, restrictor","summary":"A Ø10 steel pipe from a tapped union boss on the block flank up and outboard of the cam-cover lip into a union on the cover's exhaust wall, a restrictor in the cover-side bore at the tip; each first straight leg out of a union is at least the bend radius or the sweep refuses.","applies":["engine","cylinder head","oil feed","cam cover"],"basis":"V12 showcase CADSB-908 (Jaguar XJS-class external feed); CADSF-1517","sources":["nativecad-v12-showcase"],"tags":["oil","feed","pipe","union","restrictor","engine"]},{"id":"rotating-assembly-clash-audit","kind":"rule","tier":2,"title":"Audit the rotating assembly against the statics at several crank angles","summary":"Measure every part whose placement changes with crank angle (crank, rods, pistons, valves, cams, trigger rings, damper, flywheel) against every static part at 0/90/180/270 degrees, not only against the chain -- the V12's first such pass found 27 clash classes up to 14.5 mm.","applies":["engine","crankshaft","flywheel","camshaft","assembly"],"basis":"V12 showcase CADSB-918","sources":["nativecad-v12-showcase"],"tags":["clash","audit","kinematics","engine","assembly"],"detail":"CADSB-918: the V12 clash audit had classified rotating parts as 'other' and measured them against the timing chain alone; pass 3 found a crank turning through solid main webs (14.46 mm), a flywheel 14 mm inside the block's rear face, cam lobes 13 mm into their shaft, a crank sensor bolt in the trigger ring."}]}