Plating metal parts improves both performance and appearance, and can ensure your component functions properly in its application.
Plating—a metal finishing process which adds layers of additional metal onto existing parts and components—increases conductivity, minimizes corrosion, reduces friction, and gives products a more pleasing and polished look. Plating can also make a product thicker or magnetize its surface.
Plating may be performed before or after fabrication. With pre-plating, raw materials are plated with metal before they are shaped into specific parts. Post-plating is conducted after fabrication of the finished part.
The primary benefit of pre-plating, in most cases, is its low cost. Coating raw materials is quicker, easier, and less expensive than coating individual finished products. If large amounts of material are likely to be cut away during production, however, pre-plating may not be worth the extra material waste produced.
To determine if pre-plating the right choice for your application, ask yourself the following questions.
Will your parts be exposed to corrosion?
Pre-plating means that edges and other cut-away areas won’t be plated after manufacturing, reducing their resistance to corrosion in these areas. Pre-plating is a poor fit for caustic environments.
Does your design have complicated shapes?
Post-plating often relies on a technique called barrel plating, where finished parts are tumbled around in the plating solution in order to coat them. Barrel plating is highly economical, but it can damage fragile or more complex parts that might tangle. If the final design will be too complex for barrel plating, pre-plating will be the better option.
Will your part require significant shaping?
Extensive cutting, drawing, and other fabrication processes may leave some areas of your final product uncoated.
Does appearance matter?
If the final finish of the part is important, post-plating is most likely a superior option. While nickel and some other aesthetically pleasing metals are compatible with pre-plating, fabrication may leave the final part with an uneven finish.
Will your part be hardened with heat?
Heat treating doesn’t just affect a material’s physical properties, but often also alters chemical properties. Most heat-treated parts need to be post-plated to ensure the integrity of the coating.
Post-plating costs more than pre-plating and poses risks of dimensional issues on the workpiece. However, post-plating is also the only method that guarantees a part will be fully coated. Post-plating is an ideal—and often necessary—choice for parts that will be subject to harsh environmental conditions. It’s also an excellent choice when a visible component needs a more polished appearance.
Keep in mind that plating won’t fix imperfections in your raw materials, and it can’t smooth rough surfaces. This means that your starting surface shouldn’t be rougher than the final finish you’re hoping for.
Selecting the Right Plating Process for Your Metal Component
Whether you ultimately choose pre-plating or post-plating for your products, quality and precision are critical to your results. At Engineering Specialties, Inc. (ESI), we specialize in metal stamping safety-critical components and always maintain superior quality control throughout our processes. We’re IATF-certified, Six Sigma Black Belt trained, and our team members are experts at minimizing defects.
For your convenience, we’ve compiled a Metal Finishing Selection Guide with a chart detailing finishing solutions that improve corrosion resistance, surface hardness, and other mechanical property enhancements to their metal components.
ESI can source pre-plated materials for your projects or directly handle post-plating them. Our experts will consult with you to help you decide which is the best choice for your applications.
Contact us today to find out more. We look forward to working with you.