# Looking for a Coating Thickness Gage



## nEighter (Nov 14, 2008)

Prices for these babies start at huh, to OMG!

I would like something like this:










something similar with the sensor like it is here, corded and separate from the controls... OR can I get a reliable reading with another type? I saw that or similar model in use when I had mild steel parts for my ladder rack hot-dip galvanized to ensure I would never have it rust on me. The guy showed me a similar model to this one, we were checking the coating for thickness.

I have some metal that I need to coat here soon and need one of these to check the thickness. I am not sure on budget yet. Maybe.. $600.00? Would like much under that but I think that is about as entry level as it gets. I may be able to justify more if the model/type is better for the money.

Any of you industrial guys have one of these babies? What have you used, what are your recommendations?

I am signing all the paperwork for a Topps Roof Coating installer this week. I will have to go through their training process on their system(s). But figured this type of coating would be good to get into if you like the sun beating down on you on a roof all day long (Ewing?)


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## Rcon (Nov 19, 2009)

You can get one of these bad boys for like - free


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## premierpainter (Apr 17, 2007)

We have the PosiTector for all substrates. Make sure that it can read wood, because you never know when you might need it for siding. We take thickness measurements around the house first, mark them all down and then spray. After spraying has dried, we shoot the same spots again and check for thickness. If you don't do it that way, the meter will read total thickness, including what was on the substrate to begin with. That does not help when your trying to figure out your thickness. 
We do also use the gauge shown above, but that is a wet mil gauge, not dry.


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## ewingpainting.net (Jun 2, 2008)

Ya, there not cheap, I don't own one. I have the manufacture do the mill test, then send me a letter of what the results were. The wet mill gauge only gives an idea of what the DFT will be, and an idea will not help you if it got funky.


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## mustangmike3789 (Jun 11, 2011)

i have the positector dft gauge. the wet mill gauges can be good if you know your soilids by volume and do your wet to dry calculations but it will only read each coating as you apply it and wet film readings will not be accepted on any final reports that i know of. im not sure what your requirements for tools will be but you could use a type 1 (banana gauge) and get accurate readings on your dft. type 1 gauges will only work on ferrous metals. i get most of my tools through KTA Tator. http://www.ktagage.com/Category_Dry_Film_Thickness.asp


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## nEighter (Nov 14, 2008)

yeah I need one for ferrous and non ferrous metals. Looks like the ultrasound meters are pretty slick, they do all types of surfaces.. just reading mil thickness.

Premier thanks for the advice, it is a piece of common sense/actual knowledge I would have forgotten about until after that first job  I appreciate it man.

Aaron, Rcon.. there is NO way to do a wet test.. none so those won't work. I have a bunch laying around here somewhere.


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## nEighter (Nov 14, 2008)

I got word from a buddy of mine just now about an affordable gauge for $300-$365 range. Says they are as good as the higher end gauges.

I will more than likely get a gauge and when I grow out of it.. I will just get another one. 

Anyone else, please chime in. I will report back with what I found out.


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## Just-Ice (Aug 3, 2010)

That thing looks like something you have to breath into to start your car...


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## mustangmike3789 (Jun 11, 2011)

nEighter said:


> I got word from a buddy of mine just now about an affordable gauge for $300-$365 range. Says they are as good as the higher end gauges.
> 
> I will more than likely get a gauge and when I grow out of it.. I will just get another one.
> 
> Anyone else, please chime in. I will report back with what I found out.


 im not sure how it is where you will be working but my gauge has to be sent out and calibrated and i must have the certificate with me on my jobs. i would also invest in some plastic shims w/ a micrometer and some NIST plates to check calibration on your gauge.


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## robladd (Nov 22, 2010)

mustangmike3789 said:


> i have the positector dft gauge. the wet mill gauges can be good if you know your soilids by volume and do your wet to dry calculations but it will only read each coating as you apply it and wet film readings will not be accepted on any final reports that i know of. im not sure what your requirements for tools will be but you could use a type 1 (banana gauge) and get accurate readings on your dft. type 1 gauges will only work on ferrous metals. i get most of my tools through KTA Tator. http://www.ktagage.com/Category_Dry_Film_Thickness.asp


Did plastered llids at McCarren International Airport. The inspector was from Bectel NV he handed me a box of wet gauges and as I sprayed areas of 36 sq ft I would get the wft and toss it down to him and he signed off on it. First time that a inspector signed off on a wet gauge in my career. Dry gauges check Coatings Pro Magazine they have a big selection.


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## mustangmike3789 (Jun 11, 2011)

robladd said:


> Did plastered llids at McCarren International Airport. The inspector was from Bectel NV he handed me a box of wet gauges and as I sprayed areas of 36 sq ft I would get the wft and toss it down to him and he signed off on it. First time that a inspector signed off on a wet gauge in my career. Dry gauges check Coatings Pro Magazine they have a big selection.


If you are using 100% solids paints, a wet mill gauge will work because the numbers will not change for dry mils. If you have a lot of readings to do in a large area, dft will be an average. I just did a bridge and finished it with a clear coat @ 1 mil dft. After doing my average, the final finish was lower than the previous coating so I had to redo the average with all of my higher readings to make it jive on paper. As accurate as these gauges are, they are still just an average over a given area.


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## robladd (Nov 22, 2010)

mustangmike3789 said:


> If you are using 100% solids paints, a wet mill gauge will work because the numbers will not change for dry mils. If you have a lot of readings to do in a large area, dft will be an average. I just did a bridge and finished it with a clear coat @ 1 mil dft. After doing my average, the final finish was lower than the previous coating so I had to redo the average with all of my higher readings to make it jive on paper. As accurate as these gauges are, they are still just an average over a given area.


It was a exterior acrylic stucco paint. We had already put a coat on I believe he just wanted to see a consistent even coat applied over a given area. Can you tell us who inspected the bridge?


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## mustangmike3789 (Jun 11, 2011)

I was the QC inspector, there was a 2nd party QA inspector for the bridge contractors. Trying to get 1 mil to show up on a 4 coat system of 30 thousand sqft and hundreds of readings is nearly impossible..


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