Anodization Plant Tour Southern Aluminum Finishing
A lot of people have asked us why we don’t polish up our truck camper. I suppose people expect all aluminum campers to shine like the the mirror surfaces of airstreams at RV shows. The question comes up enough that we even wrote an article explaining why our Avion’s satin finish isn’t due to lack of care. Rather, it’s a feature: the product of anodization. Anodized aluminum is resistant to scratches, stains, and other environmental wear—ideal for a camper. One downside, however, is sourcing fresh aluminum to patch and modify our 1970 Avion C11 truck camper. Your local home improvement store likely does not keep this in stock. Instead, we have to find a specialty provider.
Southern Aluminum Finishing (SAF) primarily works with large-scale industrial projects. Hearing from a DIY camper project is a little out of the ordinary, but not as much as you might think. Because SAF specializes in anodized aluminum, and a particular camper company favored that material.
Sourcing Anodized Aluminum
We first contacted SAF in 2016 when we acquired our Avion truck camper. As pristine as the visible exterior aluminum was, it still suffered from decades of outdoor exposure resulting in galvanic corrosion from contact with the aged steel jack points, eating away at the aluminum. We needed new aluminum sheets for patching, replacements, and fresh projects like extending the cabover of our truck bed. SAF had the broad inventory to fill the need. (You can read about our matching process here)
Since then, we have even had an additional shipment of aluminum for interior work. But today marks our first opportunity to lift the veil of the anodizing process as we visit the plant where much of our camper’s aluminum originates.
Roam Lab Goes Down To Georgia
We pull into the gravel parking lot of SAF’s Atlanta, Georgia, location just after lunch on a cool fall afternoon. SAF has operated out of this location for over 75 years. In that time, the business managed to remain in the family. And our tour guide, George, is the grandson of the original founder Marvin McClatchey.
George passes us hard hats and safety glasses before we enter the first warehouse. Massive pallets of extruded aluminum wait to be anodized and shipped back to clients. SAF sources some aluminum for clients. But for specialty projects, the clients send their own aluminum parts for anodization. We pass by a series of anodized columns ready for shipping. We’ll get to see how these columns get that satin finish as we exit this staging warehouse and enter where the real action takes place.
SAF offers a variety of aluminum finishing services across its many locations, but at this location, we can see their bread and butter as a massive sheer cuts sheets of aluminum from a towering coil. These sheets are then clamped to frames before being dipped into vats of fluoride rinse, dye, acid, and water to etch, degrease, desmut, anodize, dye, and seal each sheet.
Annodization on an Industrial Scale
Large yellow cages wiz up and down the line dipping sheets into vats in varying sequences depending on the final color and hardness that is desired.
Once complete, these aluminum sheets and extrusions are shipped to the clients for architecture, product, and a wide range of other applications.
Looking at Annodized Aluminum
Once back in the fresh air (very fresh in comparison to the fumes wafting over from the acid vat), we marvel at the process. But there’s one more thing to see: samples of the final product. While we have focused on standard clear anodization for our project, the process can include a dye to create a wide range of colors. Think of all the colors that iPhones come in. Those cases are made of aluminum anodized to that color and finish.
George pulls out a collection of samples demonstrating the range of colors and the variation between them. Like a batch of paint or a pan of cookies, SAF may follow the same recipe each time they anodize aluminum but there is some variation between each batch. Seeing the diversity of tint between bronze, black, and gold anodized finishes, we better appreciate how well our aluminum sheet matches the original finish.
Anodization may be part art, part engineering, but the result is remarkable.