You should know everything about a vehicle before buying it, but sellers don’t make it easy to understand all the necessary information. In fact, some could be trying to hide details so you don’t get the car for a lower price.

You could get a report, like a CARFAX, but there’s something you need to keep in mind about those reports: not all problems appear on them.

That means that if a car was in an accident and there’s unresolved, underlying damage, you’ll be none the wiser. That is unless you use a paint thickness gauge or meter.

## What is a paint thickness gauge?

Paint isn’t magnetic, but the metal underneath it is. A paint gauge or meter is used to detect the thickness of paint. It does this by measuring the distance between itself and the magnet. Anything in between is measured and displayed on a screen.

So how does this help you, and why should you opt to purchase one if you’re going to buy a used car?

(First, here’s one of our favorites so you can understand what they look like.)

## Why paint thickness meters are important

When a driver gets into an accident and needs to fix the problem, they go to a body shop. Then technicians fix the damage, smooth it out, and spray it down. After they spray it down with paint, the car looks brand new. It seems like it’ll be easy to trick someone.

Paint meters can detect the thickness of paint in microns, which is the automotive manufacturing industry’s standard form of measurement. What you need to know is that 25.4 microns make up one mil.

Your paint meter will likely display your paint thickness in mils, so it’s essential to know. On average, an automotive manufacturer will produce a paint job with an average thickness of 2.5 to 7.5 mils.

So what happens when you use one of these paint meters on a used car? You get the results that the seller was trying to hide.

## How to use a paint meter

Place the paint meter on top of the automobile and find a steel panel underneath the body. (NOTE: Your car will not have steel underneath every square inch of fiberglass finish). Then, detect the micron or mil level.

When you get this measurement, test it against the manufacturing standards that exist in manuals or educational materials for the make and model of the car. Each brand, make and model will typically have their own specifications.

But the difference is that manufacturers are consistent throughout the entire car’s body. Body shops cannot replicate the same even-level paint job as high-end manufacturing machinery.

When you use a paint meter on the hood of a used car and continuously get significant discrepancies in the mil level, or you detect over 7.5 mils at certain points in the body, that’s how you know that the car has had bodywork.

## Don’t live and die by your paint meter, but do use it

A paint meter can’t possibly tell you everything, but it can allude to problems with a vehicle. If it has been in an accident, assess what kind of accident it’s been in. Is it a fender bender that isn’t threatening the stability or integrity of the vehicle? You can probably bring this up to the seller and pay a reduced price, but it should still be safe.

Use paint meters, but don’t treat them like the end-all, be-all. Here’s another paint meter for you to check out on the less expensive side.

### Paint thickness gauge

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