Sunon FG-4 fan guard

A metal guard for 40 mm fans, with a 32 mm mounting pitch. Sunon labels the variant FG-04 in its accessory drawing; the distributor ordering code is FG-4 (Mouser 369-FG4, DigiKey 259-1623-ND).

The model is an approximate drawing-led reconstruction, not manufacturer CAD or a qualified safety guard model. The sheet specifies 32 mm pitch, four 4 mm openings, 1.6 mm wire and 5 mm total height. Ring diameters, bends, welds and applicable tolerances are not established. Those limitations are recorded in provenance.

The zero-pin symbol represents an off-board mechanical BOM item. The footprint is a drawing reference with no copper pads or PCB drills. Its circles identify fan mounting openings; do not automatically drill a PCB at those positions. No electrical connection or grounding function is asserted.

Mounting screws, washers, retention, guard strength, blade clearance and airflow effects require assembly-specific review. No finger-access safety, IP rating or manufacturing approval is claimed. The fixed guard has no operating state; animate the fan rotor separately.

Original source and generated assets are MIT licensed. Manufacturer documentation remains linked, not redistributed. Run build_model.py with CadQuery, then convert the STEP with step2glb convert. The generator preserves all inferred dimensions explicitly.