For OEMs sourcing sheet metal components, the finish should never be an afterthought. It affects corrosion resistance, product lifespan, appearance consistency across production runs, and ultimately, the cost of quality.
Powder coating has become the preferred sheet metal finishing method for high-volume manufacturers, and for good reason. This guide covers what powder coating is, how it compares to wet paint, and what to look for when selecting a supplier.
What Is Powder Coating?
Powder coating is a dry finishing process in which electrostatically charged powder particles are applied to a grounded metal surface. The coated part is then cured in an oven, where heat causes the powder to flow and chemically bond into a uniform, durable film.
Unlike liquid paint, powder coating contains no solvents and releases negligible VOCs during application. The result is a finish that is harder, more impact-resistant, and more consistent than most wet-applied alternatives. It is available in gloss, matte, satin, and textured profiles, giving engineers flexibility without sacrificing performance.
Before powder is ever applied, surface preparation is the most critical variable. A multi-stage chemical wash removes oils, oxides, and contaminants that would otherwise compromise adhesion. The more wash stages in the process, the better the foundation for a long-lasting finish.
Why OEMs Prefer Powder Coating
OEMs running repeated production volumes need a finishing process that behaves the same way on part 1 as it does on part 10,000. Powder coating supports that requirement in several ways.
Consistency at scale. Automated gun applicators can be dialed to precise film thickness and build parameters, removing the variability that comes with manual spray applications.
Throughput efficiency. Dry powder does not require flash-off time between coat and cure. Combined with fast color change capability, powder coating integrates cleanly into continuous production environments.
Durability. The cured film resists chipping, scratching, fading, and chemical exposure better than conventional liquid coatings, which matters for components exposed to outdoor conditions, repeated handling, or aggressive use environments.
Reduced waste and rework. Overspray in powder systems can be reclaimed and reused, and tightly controlled application parameters reduce defect rates.
Powder Coating vs. Wet Paint
For OEMs deciding between finishing methods, here are the key differences between powder coating and wet paint:
| Factor | Powder Coating | Wet Paint |
| Application method | Electrostatic dry powder | Liquid spray |
| Cure process | Oven heat cure | Air dry or oven bake |
| Film thickness control | High, automated | Moderate, manual variation |
| VOC emissions | Minimal | Significant |
| Overspray recovery | Yes, recyclable | No |
| Color change speed | Fast (dry changeover) | Slower (cleaning required) |
| Edge coverage | Excellent (wrap effect) | Can thin at edges |
| Durability | High impact, scratch, UV resistance | Varies; generally lower |
| Complex geometry | Excellent with proper fixturing | Can reach some areas powder misses |
| Cost at volume | Lower per-part at scale | Higher due to material waste |
Powder coating is the stronger choice for most OEM sheet metal applications where parts are metal, production volumes are meaningful, and finish quality needs to hold up in service. Wet paint remains relevant when dealing with heat-sensitive materials, touch-up work, or very complex interior cavities where electrostatic charge cannot reach.
What to Look for in a Powder Coating Supplier
Not all powder coating operations are built for production-scale OEM work. When evaluating suppliers, the following factors separate commodity finishers from reliable manufacturing partners.
Pretreatment depth. The number of wash stages in a supplier’s pretreatment system is a direct indicator of adhesion quality and long-term corrosion resistance. A six-stage wash system is significantly more thorough than a three-stage rinse.
Cure oven capacity. Oven design determines whether a supplier can handle your part geometry, substrate thickness, and throughput requirements. Suppliers with IR boost capability at oven entry reduce cross-contamination and improve consistency on textured or crinkle finishes.
Process automation. Manual coating introduces human variability. Automated gun applicators with programmable film and build controls produce tighter, more repeatable results across high-volume runs.
Integrated fabrication. Sending parts to a standalone finisher adds lead time, handling risk, and coordination overhead. A supplier that fabricates and finishes under one roof reduces those variables.
Quality data. Ask for defect rates. A credible supplier tracks powder coating PPM and can provide documented performance over time.
Powder Coating at Haake Manufacturing
Haake’s powder coating operation is built for consistent, production-scale results. A six-stage wash system with zirconium pretreatment ensures proper adhesion, while automated Gema application provides controlled, repeatable film thickness. An integrated IR process improves coating consistency and overall finish quality.
Haake is ISO 9001:2015 certified and recorded 0 PPM defect rate for powder coating in 2025. Because fabrication, welding, and finishing all happen under one roof in DeSoto, Missouri, parts move through the process without leaving the facility, which means faster lead times and fewer handoffs for OEM customers.
If you’re evaluating powder coating as part of your sheet metal supply chain, learn more about our capabilities and contact Haake’s team for a quote.