A Guide to Aluminum Finishing: How Our Network Delivers Premium Chem Film and Anodizing

From medical devices to aerospace components, precision-machined aluminum parts are critical to many industries we serve at Focused on Machining. We manufacture a variety of high-performance components from 6000 and 7000 series aluminum, known for their exceptional strength-to-weight ratio and other advantageous characteristics.

Aluminum’s natural corrosion resistance makes it a versatile material, but proper surface finishing is essential to maximize performance and longevity. At Focused on Machining, nearly every aluminum part we produce undergoes one of two primary finishing processes: chemical film (commonly called “chem film” or conversion coating) or anodizing.

By collaborating with Focused on Machining for both CNC machining services as well as your finishing needs, you’ll have a one-stop shop experience for your aluminum projects. Through our extensive network of expert finishing vendors, we deliver fully finished components tailored to your exact requirements.

Learn the benefits of chem film and anodizing, and find out how our established partnerships allow us to offer both competitive pricing and reliable lead times for your finishing services. 

Chemical Film: The Simpler Finishing Choice

Chem film represents the more straightforward of these two processes. Parts are cleaned, immersed in a chemical bath for a specified time, rinsed, and dried. The treatment forms an ultra-thin protective barrier on the surface without affecting part dimensions. This coating is both corrosion-resistant and maintains electrical conductivity.

Chemical film treatments come in several formulations. Each formulation offers its own unique combination of benefits, including varying levels of corrosion protection, color options, weight specifications, and environmental impacts. Thanks to our broad network of finishing specialists, we can connect you with the perfect vendor for your specifications.

Chem film is particularly valuable for applications where electrical conductivity is essential, such as satellite components and military radio antennas. These parts rely on chem film’s ability to maintain proper grounding, reducing electrical interference and noise.

Anodizing: The Best Option for Maximum Durability

aluminum finishing

Anodizing is a more complex process than chem film, but it offers a more durable finish. During treatment, a part is immersed in acid while electrical current is passed through the acid bath. This creates a relatively thick new layer on the part, with approximately half of the layer on the exterior of the part and half growing inward into the aluminum.

Unlike chem film, anodizing changes a part's dimensions with its thick coating. This dimensional change requires careful control of multiple variables—including time, current, and temperature—to ensure final measurements remain within tolerance.

Anodizing creates an exceptionally hard surface with excellent wear resistance and superior corrosion protection compared to chem film. It also offers a wide range of color options, whereas chem film typically produces only clear or gold-tinted finishes.

How We Match You to the Ideal Vendor

While many shops offer one or both of these finishing services, their specialties vary significantly. Finding the right machine shop for your specific needs presents a challenge—while some projects demand premium anodizing with complex masking regardless of cost, others may prioritize quick turnaround with basic chem film.

At Focused on Machining, we are ready to discuss your finishing requirements and match your project to the ideal specialist from our trusted vendor network. Our strong relationships ensure competitive pricing and lead times, including rush options. When the parts are back in our shop, we conduct a thorough documentation review and final inspection to ensure every product we deliver exceeds your expectations.

A Single Partner for Your Next Manufacturing Project

Don’t spend valuable project time vetting and managing finishing providers. Simplify your next project by letting our Colorado CNC machine shop handle both in-house precision machining and finishing through our trusted network.

Request a quote today to discuss your next project! From titanium machining to electropolishing services, we offer a wide range of manufacturing solutions under one roof.