Answers to questions and useful information

On this page we will try to answer the most frequently asked questions. . We will also show here examples of measurements, calibration instructions, tips and even experiences using our paint thickness gauges.


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Which meter is worth choosing?
When choosing a varnish meter model from the extensive Prodig Tech range, it's worth determining our needs from the outset. Will the device be used to examine several cars or will it be used intensively for the next few years? We will only test older vehicle models, will we also make measurements on new cars that use modern painting methods and aluminum components? It all determines which varnish meter model will be right for us.

If you plan to buy a car from an older year and plan to view several carefully selected copies, a simple meter, e.g. the Prodig Tech GL-2 + model, that provides high precision at a low purchase price, will work perfectly well. If we plan to measure modern cars and we want to have access to advanced functions such as galvanized sheet detection, fast and accurate measurements also on aluminum, measurement memory or a color LCD display, it is definitely worth reaching for a professional paint meter such as GL -PRO-2 or GL-PRO-6. They provide a wide measuring range (from 0 to as much as 2000 µm) with the highest precision (up to 1 µm).

Types of Prodig Tech varnish meters:

- Standard series - affordable devices, equipped with the most important functions necessary to measure the paint coating in cars.
- Super Plus series - devices in modern housings, equipped with a useful Measurement Assistant® function.
- Premium Series - devices for more demanding users, equipped with a number of additional functions and technical solutions. Pressure measuring heads - elastic suspension of the probe front.
- Professional Series - devices for professionals, based on modern 32-bit processors and a 12-bit converter, providing the most precise measurements, including zinc detection on steel, spherical probes for measurements on curvatures.
- Magnetic Series - simple magnetic testers. They enable quick measurement with accuracy allowing to evaluate a car. Among the solutions available on the market, they stand out with a double measuring scale.

When choosing a varnish meter, it will also be extremely important to pay attention to the type of probe used. The Prodig Tech brand offer includes meters with a probe built into the meter, as well as models with a probe on the cable. The probes themselves could be flat or equipped with a ball. What are the differences between them? The probe on the cable and equipped with a ball makes it possible to make measurements in hard-to-reach places, as well as on curves, such as pillars, sills or embossing on the car body. Thanks to this, we can check whether the car was painted in any, even the most obvious place.
How to use the varnish meter?
Thanks to Prodig Tech varnish gauges, we can determine whether a given car body element has the original varnish, has been subjected to varnish or body repairs. To do this, simply start the meter and apply its probe to a selected place on the car. Measurement Assistant® built-in will help in the interpretation of results, but it is worth remembering that:

- A result of up to 70 µm can mean a polished coating of varnish.
- A result of 70 to 170 µm suggests the factory original varnish coating.
- A result of 170 to 300 µm suggests a paint repair (re-painting).
- A result of 300 to 500 µm suggests bodywork repairs.
- A result of more than 500 µm suggests repair using a metal body using a putty knife.

It is worth remembering that before measuring paintwork with a meter, it is worth washing the car. Although dirt may have a slight impact on the results, the argument for inspecting a clean car is the fact that in such conditions it will be easier for us to assess the condition of the paint coating with the naked eye and to detect any imperfections such as scratches, creases or color differences . Also, do not move the probe over the paint, especially if it is heavily soiled, as it may scratch it.
Verification of the correctness of detection of the zinc layer by the varnish thickness gauge GL-PRO-6-FAZ and GL-PRO-2-FAZ
"We invite you to familiarize yourself with the laboratory tests that we conducted on automotive sheet samples of several brands. The aim of the study was to verify the correctness of detection of the zinc layer by the GL-PRO-6-FAZ meter (also applies to GL-PRO-2-FAZ). It happened that the meter did not detect the zinc layer despite the fact that the zinc should be on steel. We checked why this is happening - we now know when the meter will not detect the zinc layer. We invite you to read, the research results are very interesting in our opinion. Click to see our research: RESEARCHAs research shows how different quality zinc coatings can be, we plan to conduct further tests."
Zinc detection on steel sheets - GL-PRO-2-FAZ and GL-PRO-6-FAZ varnish thickness gauges
"Zinc detection on steel sheets - GL-PRO-2-FAZ and GL-PRO-6-FAZ meters Paint thickness gauges GL-PRO-6-FAZ, GL-PRO-2-FAZ have a function that facilitates the detection of a zinc layer on steel sheets. This is a useful feature especially when looking for a used car. Quite often, cars after road collisions replace the entire body element, e.g. a fender. Such an element, if it is new and will be varnished according to art, is difficult to verify whether it is original or a replacement by only measuring the thickness of the varnish - indications may indicate that the element is original. Equivalents of body parts produced by various companies are often not covered with a layer of zinc. Of course, in order to distinguish such an element, the rest of the car must be made of galvanized steel, which will be detected by the meter (indication Fe + Zn). For example, if on one fender we get an indication of zinc and on the other one such indication will not mean that the element has been replaced. When measuring on galvanized steel, which the meter will be able to detect, the display will show Fe + Zn, and when measuring on non-galvanized steel, the display will show Fe.

What should you pay attention to?
Information about galvanized steel is only an approximate interpretation of the measurement and this function was introduced to the measuring needs of car bodies and for measurements in other areas, but with the proviso that we know that the tested steel can be coated with zinc and not another metallic compound with diamagnetic properties ( e.g. copper, gold) or paramagnetic (e.g. aluminum), because in this case the meter can also indicate Fe + Zn information (and not e.g. Fe + Al, Fe + Cu). The meter detects a diamagnetic or paramagnetic layer applied to steel sheet. Because galvanized steel is used in the automotive industry, the indication ""Fe + Zn"" was adopted.

The conducted tests (-> read more) show that the GL-PRO-6-FAZ and GL-PRO-2-FAZ paint thickness meter detects the zinc layer on the steel sheet when it is (this zinc layer) continuous and homogeneous. Only then are eddy currents able to ""close"". An inhomogeneous, lumpy zinc layer with numerous gaps will not be detected by the measuring instrument, which may be its additional advantage.

It should also be noted that non-galvanized car sheets can be protected in another equally well effective way and despite the lack of FeZn indication, this does not mean that the sheet metal is not protected against corrosion.

In sum: - they measure on steel without an additional diamagnetic or paramagnetic metallic layer, we will get the Fe result;

- when measuring on steel covered with zinc or other diamagnetic or paramagnetic metallic material, we get the Fe + Zn result;

- in some cases it may happen that the corrosion protection containing zinc is not detected - the zinc layer must be uniform and continuous;

- zinc spray can not be detected after application on the sheet - it does not form a homogeneous and continuous layer;

- the meter may not detect zinc if the thickness of the varnish together with the thickness of the zinc exceeds 300-350µm, then the indication will be Fe, although the steel may be galvanized.

It should be remembered that the indication of zinc on a steel plate is indicative and if we have doubts whether a given element of the car should be galvanized, it is best to contact the car manufacturer for information.

The zinc detection function on a steel plate works up to a varnish thickness including a zinc thickness of about 300-350µm."