1. We started out with an...
1. We started out with an old, some-what corroded, dashboard that needed some TLC. To achieve the desired appearance, this piece of metal needed a little work before it could be anodized.
We've all seen anodized motorcycle parts, but instead of just looking at the stuff we wanted to explore the process. Located near our offices, in Orange, California, Dunham Metal Processing and Anodizing Specialists volunteered to show us the entire anodizing process and a few of the multitude of colors available. Also revealed to us are the many benefits of anodizing, including durability, color stability, easy maintenance, and low initial costs (a lot cheaper than chrome!).
The owner of Dunham Metal Processing, Jeff Bailey, explained his methods of batch anodizing as a series of carefully controlled and calibrated stages: cleaning, pre-treatment, anodizing, organic coloring, and sealing. Check out the Dunham anodizing treatment as we snapped a few photos in its shop.
 2. With Dunham's in-house...  2. With Dunham's in-house polishing, our dashboard spent some time with the polishers under the polishing wheel. |  3. Once polished, the piece...  3. Once polished, the piece looked great, but it could still use some color. |  4. Special aluminum racks...  4. Special aluminum racks are used to support the part being anodized. Once it was racked up... |
 5. our dashboard began its...  5. our dashboard began its journey through the anodizing process, starting with a cleaning. Alkaline and/or acid cleaners remove grease, surface dirt, and polishing compound. The pretreatment is next. A shiny finish is created using a mixture of phosphoric and nitric acids that chemically smooth the aluminum's surface. |  6. Once the dashboard was...  6. Once the dashboard was prepped, it was time for the anodizing process. Anodizing creates an anodic film on and in the aluminum by passing an electrical current through an electrolyte bath while the metal is immersed. |  7. Directly after anodizing,...  7. Directly after anodizing, it is colored. There are four different types of coloring, but in this instance, organic dyeing is used. This particular process can be used to produce a wide variety of intense, vibrant colors that can't be matched by paint. It also provides excellent weather fastness and color longevity. Then, the part is sealed by closing up the pores in the anodic film, giving the surface resistance to stain, abrasion, and color degradation. |
 8. Finally, the part was cleaned...  8. Finally, the part was cleaned off once more before it was allowed to air dry. The process was then complete. Throughout the entire anodizing process, quality-control checks are made that monitor each step. |  9. Our dashboard was color...  9. Our dashboard was color anodized red, but there are thousands of color variations available, including clear, hard anodizing, and multiple color anodizing. |  10. Multiple color anodizing...  10. Multiple color anodizing is exactly the same as the regular color anodizing, except there are two more steps. Once the part is anodized and dyed, some of the original color is removed. For this wheel hub, a sponge was used to take away some of the dye. |
 11. The part was then dyed...  11. The part was then dyed again with another dip in the dye tank. The aluminum only accepts the new dye where the other color was removed. |  12. The purple and blue dyes...  12. The purple and blue dyes give the part a different look, but it still has all the benefits of anodizing. |  13. Just to show you some...  13. Just to show you some of the other colors available, here's yellow and blue... |
14. ...just yellow... | 
15. ...brown... |  16. ...and hard anodized....  16. ...and hard anodized. |
 17. After 40 years in the...  17. After 40 years in the business and three generations of anodizing, Dunham Metal Processing has a knack for producing great aluminum finishes, but it also does bead blasting, powdercoating, metal silk screen printing, and laser engraving. | | |