Powder Coating 101
Project Long Travel SCU
Sep. 01, 2006
We recently picked up our Project Long Travel SCU chassis and body panels from ECP Powder coating in El Cajon, CA. Scott Rasmussen owner and head powder coating guru gave us the full tour of his shop and an explanation of the complete process involved in applying a durable coat of powder. Since the powder coating process is quite involved, we figured it deserved its own detailed article.
ECP was started in 1970 by John and Dolores Hilton. They opened the shop and mainly did custom spray painting. Around 1988 they started offering powder coating to their customers. Scott Rasmussen, who had been working at ECP since 1979, took over the business in 2000 and expanded the operation with a larger facility and larger ovens to focus more on the off-road market. Since then ECP has grown to be one of the largest powder coating facilities in San Diego County. Scott says 50% of his work load can be attributed to off-road products, but he also coats anything metal that you bring to him such as production work on cabinets or medical equipment enclosures. Scott can also do custom lettering if the customer needs something labeled.
The first step in the process is preparing all the parts that are going to be coated. In our case it was a chassis, numerous body panels, as well as a few smaller parts. They begin by cleaning all the parts with solvent to remove any oils that may be on the metal. This is a critical step that must be completed before sand blasting in order to keep the sand blasting material clean of contaminants. The material must be free of contaminants so that the parts to be coated are not affected. Once it's clean they mask off any chrome parts with duct tape that may be welded to the chassis such as grab handles and step bars.
Once clean it gets sand blasted and then all parts are hand sanded. This is very time consuming but is necessary to remove any weld splatter or imperfections. Next they remove any dust on the parts and remove the duct tape and add high temperature tape to the chrome areas. Then it all goes in the oven to pre-heat at 400 degrees. Once the parts are hot they inspect them to see if any oils ran out of any tubing. If there is excess oil, it needs to be re-cleaned before any powder is applied.
The next step is to spray powder on the warm parts. While it?s warm they focus on the nooks and crannies (tight areas). When spraying powder there are 2 ways to attract the powder to the metal. They hang all parts on a rolling metal cart which has an electric charge applied to it, this allows for electrostatic attraction of the powder to the metal. The electric charge allows the powder to flow into every nook and cranny on the parts including all the welds. Mechanical attraction of the powder is due to parts being warm. This allows the powder to melt to metal. With the parts being warm it ensures better coverage in tight spots. Once the parts begin to cool, they cover the rest of the areas with powder and put it back in the oven at 400 degrees for 20 minutes. This step does a partial cure of the powder which allows the clear coat to better adhere to the surfaces.
Once the parts cool off to room temperature they begin spraying on a clear coat to add extra protection to the coated parts. After the clear coat is applied the parts go back into the oven for another 35 minutes. This completes the cure of the powder base coat as well as the clear coat.
We were amazed at how much work goes into the powder coating process. There are quite a few steps involved to ensure a solid coat of powder is applied and one that will hold up against the rigors that the harsh off-road environment offers. We had Scott and his team spray a silver sparkle color on our project car. When we fist saw it we were amazed and how good it looked. It really shines in the sun light! They did an amazing job!
ECP Powder Coating 619-448-3932