# Paint thickness guage.



## del77 (Aug 20, 2008)

Im looking at getting a paint thickness guage, started doing quite a few detailing jobs using DA, And dont want to end up cutting too far on someones car after not spotting a dodgy repair etc. Is it worth spending a lot on one or would a cheap one do the job. (jobs i do are only very light cutting, polishing with da). Not full on correction details. Seen a cheap one by sealey model TA091. Any advice would be great thanks.


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## liam99 (Dec 29, 2009)

Some info that might help

http://www.detailingworld.co.uk/forum/showthread.php?t=335704


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## del77 (Aug 20, 2008)

prob get hold of the one cyc are selling. sounds decent enough without being too expensive.


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## qualar (Apr 12, 2014)

Would this one be any good. Resolution is 5 microns.

http://www.ebay.co.uk/itm/DIGITAL-P..._Measurement_Equipment_ET&hash=item27e636f15d


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## Choppy (Aug 8, 2013)

this is the one i ordered yesterday which looks pretty good

http://www.ebay.co.uk/itm/NEW-DT-15..._Measurement_Equipment_ET&hash=item35cccaecde


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## -Raven- (Aug 26, 2010)

qualar said:


> Would this one be any good. Resolution is 5 microns.
> 
> http://www.ebay.co.uk/itm/DIGITAL-P..._Measurement_Equipment_ET&hash=item27e636f15d


Although PDG's are only a guide, 5 microns is too big for resolution IMO.

Have a look at the CEM DT-156 Choppy posted. There's quite a few of us that have this one, it works brilliantly. 0.1um accuracy under 50um (you're in trouble if you're paint is this thin!) and 1um accuracy over 50um.


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## qualar (Apr 12, 2014)

-Raven- said:


> Although PDG's are only a guide, 5 microns is too big for resolution IMO.
> 
> Have a look at the CEM DT-156 Choppy posted. There's quite a few of us that have this one, it works brilliantly. 0.1um accuracy under 50um (you're in trouble if you're paint is this thin!) and 1um accuracy over 50um.


Does the DT-156 work on aluminium panels?


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## nick_mcuk (Jan 4, 2008)

The problem is with all these PDG is that they only give you a total thickness reading not a break down of what each layer is.

So they are pretty much pointless unless you spend £100's or £1,000 on one that actually breaks down the layers (oh and also reads on non ferrous materials too). An overall thickness reading will still leave you guessing how much lacquer there is.

I would save your pennies and put a fraction of the money towards a scrap panel and learn how to read the paint and the warning signs of strike through.

Besides if you are using a DA it will take some going at it before you go through the paint unlike a rotary that is a lot more aggressive.


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## -Raven- (Aug 26, 2010)

qualar said:


> Does the DT-156 work on aluminium panels?


Yes! :thumb:

You actually get one iron strip for calibrating F readings, and one aluminium strip for calibrating NF readings, with the plastic thickness strips.


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## bigup (Jun 4, 2009)

i ordered a DT-156 from decent seller on aliexpress, for £64 delivered

was despatched yesterday so will wait for it to arrive before recommending buying from there!


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## shine247 (Mar 1, 2010)

Even though the lower cost PTG's do not measure layers, it is always handy to have a reading before and after buffing. It is nice to get a result and discover you have hardly removed anything.


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## nick_mcuk (Jan 4, 2008)

Yeah but its not going to help you know how much lacquer or top coat you have to work with....thats the point I am making.


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## Chrome Dome (Feb 26, 2014)

nick_mcuk said:


> Yeah but its not going to help you know how much lacquer or top coat you have to work with....thats the point I am making.


There are plenty of painted areas on most cars that have no lacquer on them, look inside boot lids and bonnets. Readings from these and the exterior panels, a bit of maths and you've got your lacquer thickness.
Might not be super accurate, but it's a fair guide without spending thousands.


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## nick_mcuk (Jan 4, 2008)

That us going to be be way out though as that is mainly overspray!

I stand by my original comment if unless you buy a proper one that breaks down the layers it's pretty much a waste of money and you are still guessing on how much top coat there actually is.


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## -Raven- (Aug 26, 2010)

They're a good guide Nick. Handy tool to have in the kit mate, easy to pick repairs etc with them too. If you touch other people's cars, they just might stop you doing something stupid.


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## fatdazza (Dec 29, 2010)

nick_mcuk said:


> I would save your pennies and put a fraction of the money towards a scrap panel and learn how to read the paint and the warning signs of strike through.


What are the warning signs? My understanding is that if you get a "warning sign" it is too late :thumb:


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## nick_mcuk (Jan 4, 2008)

-Raven- said:


> They're a good guide Nick. Handy tool to have in the kit mate, easy to pick repairs etc with them too. If you touch other people's cars, they just might stop you doing something stupid.


I dont dis-agree with the bit about finding repairs...to the untrained eye repairs can be difficult to spot and one of these total thickness gauges will help you spot this.

I have grown up round body shops and cars, one of my dad's businesses was a body shop. I have also run my own detailing business as a sideline for 4 years (I no longer do it as I just dont have the time thanks to my real daytime job), so I do know a thing or two about refinishing and paint correction.

I have never ever used a PDG...if I was to use one it would be the type that breaks down the layers and also reads on plastics.

I can honestly say in the past 7-8 years I have struck through paint maybe 2 or 3 times, two of these were freshly painted cars an it was always on an edge which no matter what you do its very easy to do....both were rectified by a simple touch up and were no more than 5mm in size, the 3rd one was on my 405MI16 and I was grinding the nuts off an area on the rear O/S door and to be honest I wasn't paying 100% attention (was silly late at night) and just blipped through.

In this time I have probably detailed and machine polished in excess of 300 cars. (everything from Seat Ibiza's to high end Super cars)

Someone asked how do you spot it well its difficult to describe but I can tell if a finish is thin...dont ask me how its just something that I have learned from young when I spent time with the painters in my dads old body shop and from playing about with scrap panels

So back to my point....is a £60-90 PDG any good....well yes if you want to see the overall thickness and if a panel has been repaired or repainted. Is it a good tool to tell you how much you can polish an area...not really as you are still guessing at how much clear coat/lacquer there actually is.


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## Guest (Jul 10, 2014)

The high-tech gauges are often shown being used without the couplant....the readings are not that reliable used in such a way.The paint layers have to vary in density for it to be accurate...Primer/Base/Clear...or the gauge will read two layers as one etc.Maybe more of a "Pros sales tool"

The PosiTector 200 probe emits a high frequency sound pulsethat travels into the coating via a coupling gel and reflects from
ANY surface that is different in density.


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## bigup (Jun 4, 2009)

bigup said:


> i ordered a DT-156 from decent seller on aliexpress, for £64 delivered
> 
> was despatched yesterday so will wait for it to arrive before recommending buying from there!


Quick update, ordered the DT-156 from AliExpress on the 7th July and it arrived today (12th July), so thats 5 days from ordering which is pretty impressive! package was marked down at $29 and labelled "Thickness meter"











now need to find out how to use it  how often do you calibrate it? and do you use the see through plates or the metal plates?


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