Step 1
Tooling and Part Loading

Step 1: Tooling and Part Loading
Our process begins with the fabrication of custom tooling fixtures to hold and mask your parts during the vacuum metalizing and painting operations. We ensure tooling fixtures provide maximum efficiency both in the number of components on a fixture and the handling of the fixture for processing, which allows for the best possible piece price.
Our goal is to ensure masking is integrated into the tooling fixtures to minimize manual processes. Any masking that is not achievable with a tooling fixture will be completed before processing.
We follow client guidelines and adhere to strict quality standards to ensure correctly processed parts. Our machine operators take several precautionary measures to ensure that no contaminants are transferred while loading the parts. Individual parts are inspected to ensure visible defects are resolved, and then loaded onto the tooling fixtures.
Step 2
Spray Coating Basecoat Application
Step 2: Spray Coating Basecoat Application
For reflective finishes and chrome or metallic coatings a specially formulated primer, or basecoat, is applied to promote adhesion and provide a smooth surface for the metalizing and paint finish. Mueller Coatings has developed proprietary coatings for many substrates, including flexible plastics, which are suited for both high and low-temperature applications.
All coatings are applied by High-Volume Low-Pressure (HVLP) spray guns using one of three different methods:
- Six-axis robotic paint cells
- Automatic reciprocating paint cells
- Manual (by hand) for low volume and prototypes.
Our robotic spray cells include eight banks, allowing us to apply a variety of coatings, such as:
- Conductive paint for EMI/RFI shielding
- Metallic paints
- Basecoats and topcoats for vacuum metalizing
After paint application, the tooling fixtures are placed into convection ovens for curing.
Step 3
Vacuum Metalizing Process
Step 3: Vacuum Metalizing Process
First, the tooling fixtures are placed into carousels that are loaded into the vacuum chamber. A predetermined vacuum level is reached before a current is sent to the evaporation source. The source is a tungsten filament loaded with an alloy, most commonly aluminum. The current heats the filament until the alloy evaporates, forming a vapor cloud that bonds to the parts.
The tooling fixtures rotate in front of the evaporation sources to achieve a uniform coating. Upon completion of the metalizing process, the chamber is returned to match the atmosphere, and the tooling fixtures are unloaded.
Our proprietary EMI/RFI shielding process allows us to evaporate up to 20 microns of aluminum. The typical thickness of evaporated aluminum for light reflectors and chrome decorative coatings is approximately 1,000 angstroms. In-chamber pretreatment and post-treatment processes aid in the adhesion of the coating.
Step 4
Spray Topcoating Application
Step 4: Spray Topcoating Application
When required, a topcoat is applied to enhance resistance to moisture, abrasion, and chemicals. Mueller provides several functional and decorative topcoats including:
- 2K urethane and UV cured abrasion resistant clear coats
- Functional industrial coatings such as Teflon and ceramic coatings
- Dyed and tinted topcoats giving the appearance of gold, bronze, colored chrome, and metallic satin finishes
All work is done in a clean and responsible manner to produce the best finish with the least impact on the environment.
Connect with Us
At Mueller Coatings, we combine advanced vacuum metalizing with precision spray coatings to deliver superior results. Our vacuum metalizing process ensures a uniform coating without excess buildup, while our spray coatings provide a strong adhesive base and customizable top coats for both functional and decorative purposes.
Executed by a team of engineering experts in our state-of-the-art facility, our process is designed to meet the highest standards. Discover why Mueller Coatings is the right choice for your next project.