How To Use Coating Thickness Gauge

While you have been researching and learning how to polish and correct the imperfections in a car's paint, you have probably come across many people mentioning a "paint thickness gauge" or a "coating thickness gauge". It seems like a lot of the pro detailers are using these while doing consultations and before any paint correction jobs. The importance of these handy little devices may not be obvious to most, so you have probably been left wondering...

What is a Coating Thickness Gauge and what is its Purpose?

A Coating/Paint Thickness Gauge is used to measure exactly how thick the layer of clear coat/paint is on the car. Once you know how thick these layers are, you will know how much of the surface you can abrade away without burning through the clear coat or paint. By taking this measurement at several different point on the surface, you can figure out how much you should polish to get an even surface!

Now that you know what it is, how can you best use it?

What professional detailers use a paint thickness gauge for the most is almost as an insurance policy. When a customer wants to have the defects taken out of their paint, a professional detailer needs to know how safe it is to do that. If they don't know how thick the clear coat, paint, and primer layers on the car's panels are, they won't know how far they can abrade the surface without burning through them. By using a thickness gauge before polishing, they will know how much more it can be polished, roughly how much work has been done on the car before, and whether they will be able to meet the customer's expectations without causing serious damage to the paint surface.

Most factory (or OEM) paint jobs are about ~4 mils (~100 microns/micrometers) thick. This does vary from car to car (even identical cars that were painted in the same factory, on the same day!), but this is the general average. If the paint is thinner than that, that means that it has likely had work done on it before, so you have even less tolerance when polishing.

The goal is to NEVER polish away the clear coat! This ensures that you will never risk burning through the colored coat of the car and cause visible damage. The clear coat is usually about 1.5 mils (~40 microns/micrometers) of the total paint thickness. So, to play it safe, you should try to make sure the paint thickness gauge reads at least 2.8 mils – 4 mils thick in any given spot!

Now that you know what a paint thickness gauge is and how to use it, you can pick up one of your own and start polishing with confidence!

The Speed Master Professional Paint Thickness Gauge is a great choice for detailers of any experience level! The Speed Master Professional Paint Thickness Gauge can complete 10 measurements per second so you can quickly determine how much you can polish the paint and how safe it is to do so! The Speed Master Professional Paint Thickness Gauge pairs with an app on your phone via Bluetooth, so you can check the readings easily and conveniently any where you go! You'll never be left guessing during a consolation when you've got the Speed Master Professional Paint Thickness Gauge!