Understanding Mil Thickness
What is Mil Thickness and Why Does it Matter?
In the world of coatings, mil thickness is a critical factor that directly impacts the performance and longevity of a finish. But what exactly is mil thickness and why is it so important?
What is Mil Thickness?
What is a Mil?
Mil thickness is a crucial measurement in both powder and liquid coating applications. A mil is a unit of measurement equal to one-thousandth of an inch (0.001 inch). In the coating industry, mil thickness refers to the thickness of a coating layer measured in mils .
Why is Mil Thickness Important?
Understanding and controlling mil thickness readings during the application process is essential for achieving a quality finish with optimal efficiency. These measurements can greatly improve the cost-effectiveness of your applications by ensuring you’re not putting too much paint onto the part. If mil thickness meets specifications, it will ensure:
- Protection against corrosion, chipping and other damage
- Appearance
- Performance and durability
- Consistency and quality control
- Cost optimization
Manufacturer Specifications and Reasoning
Mil thickness requirements depend on the manufacturer’s specification. Some considerations include:
- Functionality vs. Appearance: Balance between protection and aesthetics.
- Industry Standards: Different industries may have specific requirements based on performance needs.
- Substrate Used: If the substrate is sandblasted, it will require more mil thickness compared to a substrate prepped chemically.
Measuring Mil Thickness for Coatings
Many manufacturers perform dry film thickness (DFT) readings, which measure mils after the paint has fully cured. We often recommend implementing wet film thickness (WFT) readings to add a preventative measure to production processes.
Using a wet film thickness gauge will help applicators ensure a sufficient amount of coating is applied before the coating dries – allowing them to adjust as needed without having to wait for the part to be fully cured. We use a coat master tool to read uncured powder mil thickness before the baking cycle. This greatly reduces the need for rework, enabling applicators to make adjustments during the coating process.
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How Can Sherwin-Williams Help?
Have a question about mil thickness? Our team is here to help. Get in touch with a local representative today for support.