Why the paint thickness meter is most used in second-hand cars? second-hand car dealers use this paint thickness meter to judge whether there has been an accident on the car , and whether this place has been scratched with putty. Has it been painted? From the side, it can reflect whether the car has been involved in a collision, and how big the accident was during the collision. The more severe the environmental deformation, the thicker the putty must be scraped when repairing it.
The use of the paint thickness meter is very simple. Press it to start it. If you see it, it will automatically shut down when you don’t use it. Its working principle is to use the probe to hit the metal cover, and then bounce back to read the thickness between the sheet metal and the paint surface, and the number will appear.
So how do we use a paint thickness meter to judge whether a used car has had an accident?
The thickness of the paint surface of each car is different. For Japanese cars, the paint surface is relatively thin. For American cars, the paint surface is relatively thick. The paint surface of each car is different. The thickness of the surface is not uniform, so we first need to take a standard value on the car as a reference.
Where is the standard value taken? It’s on the roof. Why is it the roof? Because there may be collisions all around, and the probability of repairs is relatively high, so you can’t use it to make the standard value, so you have to Take a standard value on the roof.
When testing, it must be placed flat. Don’t put the paint thickness meter on it at an angle. Put it like this, and take a few points. This is how you look at it. Its unit is microns Ah, is it you who take 5 points in different places? If it is okay to take 5 points in one place, it happens that a rock fell on this place, a hole was smashed, and it has been repaired. Then the standard you took is not Wrong, so take a standard value in 5 different places.
Like this value is 97.4 microns, look at it this way, this is 109, see, this is 92.5, okay, this is 110, I won’t order it if I don’t see it there, is it good to take 5 points? What is the average value of this car? Does it fluctuate around 100? Does it fluctuate around 100? For the sake of easy calculation, we take the standard value of this car as 100 microns, which is the standard value of this car. It is 100 microns.
With the standard value as a reference, we can judge, if it is far beyond this value, it shows how the place is, has it been repaired later? A deviation of 20 microns is normal, that is, if you take 100 microns as the standard value, how much is it up, it is normal within 120 microns, and the value of 80 microns down is normal.
Why does he allow this deviation? It is because when you spray paint, if you want to paint the car door, can the spray gun paint the car and the car door all at once, and he cannot spray it. Is it on him? After spraying, go down. In the process of walking, there may be a place in the middle that will be sprayed thinner. If the reading exceeds 120 microns, and it reaches 200, it means that this place must have been painted, that is, the outside The paint has been scratched, but there is no sheet metal on the inside, it may only be slightly deformed.
So if there are large value on paint thickness meters, what does it mean? The larger the number, the better the sheet metal of this place, and the more serious the impact deformation. If there are hundreds or thousands, it means that the putty on this piece is thicker, and the impact is very serious now. The value may reach several thousand, two or three thousand, or even five or six thousand. If the putty is too thick, the probe of the paint film meter will not be able to detect it, and the signal will not rebound. Yes, if the paint thickness meter can't detect it, it means that the paint surface is relatively poor.
Another situation is that the reading is very small. If the door is tested by a paint thickness tester, the reading is only 60 and 70 microns. It means that the door may be a sub-factory part, but he took it out of the sub-factory part. This door is usually colorless, why?
Because it is a white car today, and it may be a black car tomorrow, you can’t spray the paint first, so they are not painted, so they need to be painted after the auto repair shop. The original car paint is sprayed in the workshop. There is definitely a difference from manual spraying. Most of the paint film meter readings sprayed out will be a little smaller, only 60-70 microns. The side can also reflect the extent of the car accident. Generally, changing the door is not a small accident.