Precision-engineered galvanized sheet chassis enclosures built to your exact specifications
From initial concept to final delivery –every detail of this custom fabrication project
As demand for portable high-fidelity audio keeps growing, a leading audio brand launched a 2026 program to refresh its USB amplifier box line. The chassis had to act as the core protective shell for amplifier modules, USB interfaces and circuit boards while balancing corrosion resistance, rigidity, precise interface alignment and cost.
The brief called for +/-0.04mm dimensional tolerance, an 8-10um galvanized layer, reliable heat dissipation and seamless matching with every USB and audio port.
Galvanized sheet is beautiful on the shelf, but it is unforgiving in production. The client had already suffered peeling zinc, scratched panels and misaligned ports at previous suppliers, which led to poor connector fit and warranty returns.
The hardest problem was protecting the zinc coating while still forming tight interfaces. Laser heat, clamping pressure and bending all threatened to damage the galvanized layer, and even a tiny port offset meant the USB connector would not seat.
Sanjun rebuilt the process around the zinc layer rather than against it. We used an 8000W fiber laser with nitrogen assist to minimize the heat-affected zone, custom anti-scratch fixtures on the press brake, and secondary galvanizing repair at every cut and bend edge.
For the ports, laser positioning and precision punching were combined, with sample assembly against the client’s actual USB and audio connectors before mass production. FEA optimization added lightweight internal ribs and the high strength-to-weight 1.0mm galvanized sheet cut overall chassis weight by 15%.
The 3,000 sets were delivered four days early with a 100% pass rate across CMM dimensional checks, 48-hour salt-spray tests, heat dissipation trials and interface fit verification.
After five months in the market, the client reported a 30% drop in chassis-related after-sales requests and an 18% rise in amplifier sales. They then signed a three-year strategic partnership covering all future USB amplifier and new audio equipment chassis.
Sanjun understood galvanized sheet the way few suppliers do. The ports aligned perfectly out of the box, the finish stayed consistent across all 3,000 sets, and our chassis-related warranty claims dropped by nearly a third.
Eight reasons global brands partner with SanJun Hardware for precision sheet metal fabrication
Quality-managed production with documented processes and full traceability at every stage.
Streamlined scheduling and capacity planning ensure your orders ship when promised.
Expert design-for-manufacturing review at no cost –optimize your design before production.
Sheet metal ±0.1mm and CNC machining ±0.01mm –consistent accuracy across every batch.
From laser cutting and bending to welding, coating and assembly –all under one roof.
CMM inspection, coating adhesion tests, and 100% final inspection before every shipment.
Prototypes from 1 unit to production runs of 10,000+ –scalable capacity to match your needs.
Work directly with our engineering team –fast responses, clear updates, no middlemen.
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