Ok so here's a new product that I added to my store. I realize that very very few if any of you would even buy one of these, but should you ever be in the market for you, atleast you'll know where to buy one. And for the rest of you, maybe you'll learn a few things about the tool that all serious detailers and paint polishers should have in their tool box.

The ETG or Electronic Thickness Gauge goes by a few different names. Sometimes it's called a electronic coating gauge as well. ETG is actually a brand name as well, so it make things a little confusing.

The purpose of the tool is to measure the thickness of paint on your car. Remember that it's measuring 3 layers of paint. Primer, Base Coat (BC), and Clear Coat(CC)--as one giant thickness.

The Primer would be the thinnest coat, so the BC and CC could be approximated as similar in thickness.

If this is an electronic thickness gauge, are there mechanical gauges too?
Yes! There are tools that are both destructive and non destructive, and of course you don't want to scrape your paint just to find out how deep it is do you? LOL.

Destructive


There are also very simple magnetic tools that look like mechanical tire pressure gauges that you stick to the car, and pull it away, until the attraction is lost--and at the point it breaks away, the calibrated stick pulls out of the body showing how thick the paint is.

Read about how the mechanical gauge work by viewing the patent
http://www.freepatentsonline.com/4392305.html

ETG's range in price from $99 to $5000 depending on sophistication. The least expensive ones only measure paint on steel, not aluminum. The cheaper no name ones also tend to be flaky in terms of reliability. I bought one from Hong Kong a few years ago for $200. It's still sold today, but more than half the times I used it, it would fail to take a reading. And it's not like I could send it back to Hong Kong for repair or replacement.

So here is my gauge that most places sell for $500-$600.

It measures the paint thickness on steel and aluminum. It auto senses and tells you the material. It won't measure paint on plastic bumpers or fiberglass parts--for those you will need the ultra expensive $2500+ gauges.

http://www.showcarsupplies.com/shopexd.asp?id=168&bc=no

Includes a handy carrying case plus a small pouch for the gauge itself






MINI paint is similar to BMW paint and ranges from 4 to 5 mil.
1 mil = 0.0254 millimeter or 1 mil = 0.001 inch
25 microns = 1 mil. 1 mil= 1 thousandth

Human Hair is 3mil
A single sheet of paper can be 5mil (remember your paint would have primer, basecoat, and clearcoat in that thickness!!!)

So why would you need one??
If you're ever wetsanding your paint, it's important that you don't shave off more than .3 mil of paint otherwise you run the risk of clearcoat failure.

If you're thinking about moving up to a rotary buffer from the PC, then an ETG will help you prevent making costly mistakes.

If you're thinking about buying a new car or an old car, and want to confirm whether it's been repainted or not, this is a tool that could tell you in seconds. Repaints over existing paint and panels covered with Bondo will read very thick as well.

 

Yikes !


OG, neat device.

A bit OT, but in some other thread (which I cannot find now) you had mentioned the clearcoat (only) thickness on the MINI. Was that simply half the color + clearcoat thickness? Thanks.

 

You can pretty much assume that the measured paint thickness is going to be mostly basecoat and clear coat. Primer is very thin compared to the two and of course the most recent builds (I believe from 2007 on) don't have primer either, so just basecoat/clear coat.

Richard

 

How thick is the clearcoat alone though? About half the overall thickness?

 

That's what I'm saying, there is only one tool that I know of that can tell you the thickness and it costs anywhere from $2500-$5000, and it will give you the thickness of primer, basecoat, clearcoat.

Without that tool, you pretty much just have to guestimate. If they shoot 3 coats of base, they are probably going to shoot atleast that much clear or more. Btw, 3 is a number I made up--just using a number here. I know I've seen people use that above tool to make paint measurements and the Primer thicknesses are almost always wrong because it's so thin, that it cannot be accurately measured. So the first two layers are combined.

Richard

 

The guage with the teeth is called a Wet Film Thickness gauge and is used when setting up a paint application system to make sure adequate coating is applied. It cannot be used on a cured finish. It will also leave dimples in wet paint that will not disappear when the paint cures.

As OctaneGuy says, the magnetic and electronic gauges (know as Dry Film Thickness Gauges) work well on painted steel and aluminum and do not work on plastics. DFT gauges are available for use on non-metallic substrates, but are very expensive.

 

OK, thanks.

 

I'm in the car business, this is what I use when inspecting trade-in's, and it costs anywhere between $700-$800. It's not for novices, you should know how to use it, as every manufacturer paints cars with different thicknesses and you should have some sort of idea what ranges of thickness between manufacturers are within their paint standards.




http://www.elcometer.com/internation...0pages/311.htm

 

+1

Used that same device for many years for the same purpose as you, and it is very good.