Paint Meter?

[Paint-Shield]

I would assume if people are wet sanding factory clear coat they are using a Paint Meter to make sure they don't compromise the clear. So could some of the experts recommend the Meter they are using and recommend some issues you have encountered while using a Paint Meter.

As you can tell I am just starting to learn about this, so any information from the pro's would be very much appreciated.

[Mike Phillips]

I would assume if people are wet sanding factory clear coat they are using a Paint Meter to make sure they don't compromise the clear. So could some of the experts recommend the Meter they are using and recommend some issues you have encountered while using a Paint Meter.

As you can tell I am just starting to learn about this, so any information from the pro's would be very much appreciated.


Over the years I've had experience using the following Paint Thickness Gages

ETG-A Paint Thickness Gage
http://www.autogeekonline.net/gallery/data/719/etga.jpg

Quanix 4500 Paint Thickness Gauge
http://www.autogeekonline.net/gallery/data/719/quanix4500.jpg


And the one we now carry in the AG Store

Defelsko PosiTest DFT Combo Electronic Paint Thickness Gauge (http://www.autogeek.net/paint-thickness-gauge.html)


Out of these 3 I've personally used, one of the reasons we carry the PosiTest PTG is because of it's accuracy and ease of use, right out of the box there's no calibration necessary in order to use it successfully, if fact after it's delivered to your door you can take it out and start using it immediately. You can calibrate it if you want to and it's easy to calibrate.

It also has a large, easy to read screen and the display is flippable, that means with the push of a button on the side of the tester the screen will flip 180 degrees so you can easily read it upside down.

Some other important features,

The PosiTest measures both steel and aluminum, most PTG's only read steel.

The PosiTest is what's called a 3% gauge most PTG gages are 5% gages, the difference is that PosiTest give you a more accurate reading of paint thickness and when working on paint that's thin to start with that's a key difference.

Measures in mills and microns, your choice.

There's other cool features too but these are the features that mean the most when trying to measure accurately how thick or thin the paint is you're working on.


Stepped outside and snapped this pictures to show the large screen and the ability to flip the screen and what a handy feature that is.


http://www.autogeekonline.net/gallery/data/719/PosiTest002.jpg

http://www.autogeekonline.net/gallery/data/719/PosiTest001.jpg

http://www.autogeekonline.net/gallery/data/719/PosiTest003.jpg

http://www.autogeekonline.net/gallery/data/719/PosiTest004.jpg

:)

[Paint-Shield]

WoW, thanks for the informative post.

Does anyone else have any history with the PosiTest PTG or any other Gauge or Meter on the market? This purchase tends to be a large investment on my part, thus any opinions would be very helpful.

The PosiTest seems very easy to use and understand.

[Paint-Shield]

& just as a follow up.
I see the Meter reads between 3.8 and 4.5 "mils", which I assume is a Millimeter. But I have a few more questions if anyone is willing to lend a hand to someone trying to learn.


What would be a unsuitable number on the PTG for continuing aggressive work (Wet Sanding/Heavy Cutting) on a clear coat?

What should the number read for the clear coat to be considered satisfactory and not compromised?

Does that number read the depth of the Clear & Paint? Or just the Clear?

How does it work with "Single Stage Paint"?

Does the Meter/Gauge read just the small area it touches?

Where would I look for the most commonly compromised areas if I happened to work on an entire vehicle?

To me, this seems like a lot of questions. I appreciate anyone who even reads them, or finds the time to add some assistance. Wet sanding I believe is the gradual next step in my career as a detailer, and a Meter/Gauge and experience will be very valuable.

Thanks in advance!

[Mike Phillips]

Lot of great questions there but let's take a look at the bigger picture...

What are you working on?

Or what portion of the market are you trying to get into?

A paint thickness gauge is a handy tool but it's also just an indicator as it measures total film-build, regardless if it's a single stage or bc/cc finish.

Are you wanting to get into wet-sanding? Is this the direction you want to go or are you mostly just doing a lot of heavy compounding to neglected finishes?

If you're getting into wet-sanding then is it for fresh paint or factory baked-on paint?


:)

[agpatel]

& just as a follow up.
I see the Meter reads between 3.8 and 4.5 "mils", which I assume is a Millimeter.


1 mil = 1⁄1000 inch = 0.001 inch = 25.4 micron

I normally measure paint in micron as it is a smaller unit and get a little better idea. But as Mike said, overall paint thickness can only tell you so much, unless you get up to the high end PTG that are in the 3-5k range you can not tell individual paint thickness layers.

[Paint-Shield]

Thank you for all the info:

We are dealing more with factory paint then any custom work, and have just encountered a nasty water marked land rover, thats how all this research came about. I am looking for general info on wet sanding and the proper techniques so i don't cause damage but can correct deep imperfections. We used Meguiars M105 with a LC orange cutting pad on a PC2474 and had little success.

Thank you for the info and any techniques you could share would be greatly appreciated.

[Mike Phillips]

Thank you for all the info:

We are dealing more with factory paint then any custom work, and have just encountered a nasty water marked land rover, thats how all this research came about. I am looking for general info on wet sanding and the proper techniques so i don't cause damage but can correct deep imperfections. We used Meguiars M105 with a LC orange cutting pad on a PC2474 and had little success.

Thank you for the info and any techniques you could share would be greatly appreciated.

This has to do with Type II Water Spots, Type I are mineral deposits on the surface, Type II are etchings in the paint.

The only way to remove Type II is to level or flatten out the surface and this means removing a little paint. That's where the risk comes in, factory paint is typically thin, so there's not much to remove in the first place.

I'm not going to go off on a rant right now although someday I might, suffice to say car manufactures always put on the least amount of paint when the end-user wants an ample amount of paint, (whether they know it or not).

Car manufactures never ask for paints for the cars they build that the average owner can work on and they don't put enough on so that you can remove a bird dropping etching from the finish and then in the same area maybe remove some scratches and still not have to worry about going through the clear.

If you want to do wet-sanding, cutting and buffing, you really want to get a rotary buffer and some high grit papers.

A DA can remove sanding marks but not as fast as a rotary. If you want to stick with a DA style than upgrade to the XP model or a Griot's ROP or a Flex 3401, all have much more power than the first generation PC's.

:)

[frosty]

I'm starting to research this as well. From what I can tell, unless you go to the $2500+ variety that will give you a reading on different layer thickness, do these gauges really do that much good? It seems their use is more geared to somebody buying a car to determine if the car has ever been painted.

Unless you know the complete history of a car and it's paint layer thickness do you really get enough info out of these to where you can really sure of what you have to work with.

An example, say you get a 4 mill reading on a car but specs say factory paint is anywhere between 4 to 5 mils of thickness. How do you know from the factory it wasn't at 5 mils and somebody has already taken 1 mil off and may be down as far as it should go.

One counter to that may be that you'd see reading at 5 mils in some places as the entire paint probably couldn't have perfectly been taken down exactly 1 mil. That leads to a question of ok, are factory paint jobs precisely applied to where you'll get the same reading on every panel at any part of the car?

Again, I'm thinking of getting one myself and part of what I'd like to have it for is to use on any car I buy. But the other justfication of the cost would be to use it in paint correction. However, I haven't convinced me these types of gauges would provide anything more than a false confidence because really with them there's no full proof way of knowing how thick the clearcoat you're working with is.

With that said, the gauge mentioned here seems to be nice. But I've also seen the HighLine Meter used by several people and decent remarks. I won't list a link to it but the price point is quite a bit better and going off the specs I don't see one any better for the price?

Thoughts?

P.S. One other thing, does anybody know how these things read if they go over a section in a car that has some kind of body filler?

[sullysdetailing]

I would assume if people are wet sanding factory clear coat they are using a Paint Meter to make sure they don't compromise the clear. So could some of the experts recommend the Meter they are using and recommend some issues you have encountered while using a Paint Meter.

As you can tell I am just starting to learn about this, so any information from the pro's would be very much appreciated.
Auto Geek cares Defelsko PosiTest DFT Combo Electronic Paint Thickness Gauge
Defelsko Paint Thickness Gauge, Paint thickness meter, coating thickness gauge, auto paint meter, car paint meter (http://www.autogeek.net/paint-thickness-gauge.html)

It works very well but only works on metal so it wont work on cars like vettes.

**You Dont want to wet sand a factory painted car. If you do you are looking for trouble

[frosty]

Auto Geek cares Defelsko PosiTest DFT Combo Electronic Paint Thickness Gauge
Defelsko Paint Thickness Gauge, Paint thickness meter, coating thickness gauge, auto paint meter, car paint meter (http://www.autogeek.net/paint-thickness-gauge.html)

It works very well but only works on metal so it wont work on cars like vettes.

**You Dont want to wet sand a factory painted car. If you do you are looking for trouble

When you say it works well, what you would consider it works well for? I assume it works well and is accurate telling you the depth of all the layers of paint to the metal but it doesn't really give you any clue how much clearcoat you have to work with, correct? Or is there a trick I'm missing that you could use something like this to figure out the clear coat depth?

[frosty]

In searching for an article on Rotary Best practices, I found a link to this forum. It does a pretty good job of talking about PTG's and how to use them with some guess work to determine what you're working with.

Machine Polishing by Rotary Polisher - Full Guide - Detailing World (http://www.detailingworld.co.uk/forum/showthread.php?t=66024)

About a 1/4 way down in the page.
Search for "ASSESSING THE PAINTWORK"

[Misha]

i guess my first post

i got Highline II PTG about a month ago for $225 from them. then got cen-tech PTG from harbor freight couple weeks ago(it was $10) so why not

i do use them for wetsanding and for paint correction, recently used on M3.

if you dont have any of those or others for that matter, BE very carefull or dont do it at all.


HL II i think is very good gauge and nicely priced. some might start bashing that its not acurate(mostly it will be ppl with 2-3K paint gauges) but its pretty damn acurate, within 3-4 microns of actual reading. and guess what its good enought to tell you if you can wetsand or not or do any correction on paint for that matter

[frosty]

Misha,

That's exactly the one I've been looking at. Just can't bring myself to dump $700 and find out there is a $200 that works just as well.

Would you mind clarifying what makes you feel it's fairly accurate? Do you have a 3 or 4k PTG as well that you are using to gauge to make that statement?

Whatever tests you are doing to verify it's accuracy, would you mind sharing?

[Misha]

Misha,

That's exactly the one I've been looking at. Just can't bring myself to dump $700 and find out there is a $200 that works just as well.

Would you mind clarifying what makes you feel it's fairly accurate? Do you have a 3 or 4k PTG as well that you are using to gauge to make that statement?

Whatever tests you are doing to verify it's accuracy, would you mind sharing?


no dont have 3-4K paint gauge. i think one of main differences for those high price gauges is couse they work on plastic and can tell you how much of clear, base and actualy paint there is on metal or plastic(not just total amount of paint). plus other bells and wisles you can live without

paint meter comes with test strips that you calibrate almost each time u use it. and you can see how far reading PTG takes compared to number on strip. on 100 micron strip mine reads usualy 103 so its pretty damn acurate, higher prices might tell you little close to 100 but how close do you need it. unless you doing 500000 car i dont think u need too acurate

my $10 PTG reads just as acurate
here is readings from that gauge (only problem with it is its not as comfortable to use)

Math
((Reading - Plastic Shim Preordained Measurement) x 100) - 100 = Percentage over Plastic Shim Preordained Measurement

first reading Cen-tech. second reading HL II

46 Microns: Readings
46 +0%
46 +0%
46 +0%
46 +0%
47 +1%
Average Percentage= 0.2% @46 microns

96 Microns: Readings
101 +4%
99 +2%
101 +4%
103 +6%
99 +2%
Average Percentage= 3.6% @96 microns

249 Microns: Readings
253 +3%
253 +3%
255 +5%
254 +4%
253 +3%
Average Percentage= 3.6% @ 249 microns

505 Microns: Readings
484 -2.20%
483 -2.3%
482 -2.4%
482 -2.4%
479 -2.7%
Average Percentage= -2.4% @ 505 microns


is there tool review section on this forum? id post review there