How to, Paint depth test

Measuring paint thickness is a great way to ensure consumer value and helps maintain

profitability by checking if the paintwork has had any repairs which could indicate damage or an accident.

The paint thickness should sit within the range of 1.5-2.0 mils (30-50 microns) to protect the

base layer from a hostile environment while providing both depth and a durable , glossy

appearance. To measure the paint depth a hand-held, non-destructive paint thickness gauge is best.

Unfortunately theres no target depth or thickness when it comes to paintwork on a vehicle as

manufacturers make many different models with a wider variety of paint formulations and

specifications. Some vehicles may only have 3 mils (75 microns) of total paint thickness on the roof, while some SUVs may have 17 mils (430 microns) on their rocker panels. Some vehicles are repainted at the factory when flaws are detected during manufacture.

Typically however a vehicle from the factory will have between 4–7 mils (100–180 microns).

What your looking for is consistency, measurements taken from across a panel should show

small variations in thickness and any areas of reduced thickness could be a cause for concern, areas of a much greater thickness may indicate rework. If the gauge doesn't give a measurement it means that the thickness is over the gauge's limit and could mean the presence of filler and a likely repair.

So how do you use the gauge? The first thing to understand is the display, you will see both F

and N. “F” stands for ferrous metals (e.g. steel) and it means a magnetic principle was used to

obtain the displayed measurement. “N” or “NF” or & "Fe” stands for non-ferrous metals (e.g.

aluminium , copper, etc.) and it means an eddy current principle was used to obtain the displayed measurement.

All you have to do is place the gauge on the metal and the display screen should show the paint thickness measurement, be sure to read over the user manual that comes with

your device as some may work different than others.