How thick is your paint compared to common items: Pictures and Writeup.
Modern paint systems start with a primer/etcher that is applied over the substrate (body panel). Increases in body panel manufacturing have lead to thinner and thinner layers of primer. On most modern cars the primer is .3 to 1.5 mils thick. On older vehicles a thicker primer was used to hide the inconsistencies in the panels.
The primer seals the substrate from the environment (preventing rust or oxidation). After the primer has been applied the body panel is given color by the base coat (often referred to as the color coat). The base coat is usually flat or semi-gloss in nature. Again with modern paint systems the tendency has been to limit the thickness of the base coat; just enough is applied to ensure even and consistent color. The base coat can range in thickness to just over .5 mils to 1.5 mils in thickness.
If the paint is a pearl, candy, or metal flake some base coats may have flake or pearlizer mixed into them . Other paint systems may receive additional layers of flake or pearlizer on top of the base coat to add this effect. The thickness of these extra coats can vary wildly by manufacturer but most often range between .3 mils and .8 mils thick.
The upper most paint layer is the clear coat. Clear coat is a clear (pigment-less) paint that is responsible for the UV protection of the layers underneath it, as well as the gloss and shine of the paint. When we polish modern paint systems we are actually polishing the clear coat. The clear coat varies in thickness from approximately 1.5 mils (thin) to 4 mils.
Typical Thicknesses
Primer: .3 - 1.5 mils
Base (color) coat: .5 - 1.5 mils
Specialty coats (optional): .3 - .8 mils
Clear coat: 1.5 - 4 mils
How thick is a mil exactly?
A mil is a standard unit of measurement meaning one thousandth of an inch, or .001 of an inch. In other words, it would take 1000 mils to make an inch.
Paint is also measured in microns, which is a metric unit of measure meaning 1 millionth of a meter. There is approximately 25.4 microns in 1 mil.
How thick are standard items around the house compared to the clear coat found on most vehicles?
I used a Defelsko PosiTest DFT Paint Thickness Gauge to measure the thickness of various items at my disposal.
http://i184.photobucket.com/albums/x...hickness/2.jpg
It couldn`t be easier to measure the thickness of paint (or any item on a metal table). Simple hold the meter at a right angle to the material being measured and press lightly down. The machine does the rest. The total thickness on this repainted panel (used for testing) was quite thick: 13.6 total mils.
http://i184.photobucket.com/albums/x...hickness/3.jpg
Those who have ordered from Autopia-CarCare.com have received one of these gorgeous thank you letters made of high quality copy paper. It measured 3.9 mils thick, which would be a very thick clear coat.
http://i184.photobucket.com/albums/x...hickness/5.jpg
Standard printer paper was next. It was the 3 mils thick.
http://i184.photobucket.com/albums/x...hickness/6.jpg
A standard sandwich bag is very thin. Double stacked it was 2.2 mils thick, measuring just one side of the bag resulted in 1.1 mils.
http://i184.photobucket.com/albums/x...hickness/7.jpg
Fully printed magazine cover.
http://i184.photobucket.com/albums/x...hickness/8.jpg
I attempted to measure a CD/DVD, but it was too thick to get an accurate reading. The Defelsko PosiTest is accurate to 40 mils, which suggests that the CD was significantly thicker.
http://i184.photobucket.com/albums/x...hickness/9.jpg
A credit card, measured on the thinnest point.
http://i184.photobucket.com/albums/x...ickness/10.jpg
And finally a dollar bill.
http://i184.photobucket.com/albums/x...ickness/11.jpg
When we are talking about removing paint defects from modern clear coats it is worth repeating the point that they are thin (from a sandwich baggy to a dollar bill thick) and ultimately we don`t want to remove more then 10-20 percent of this. High quality, modern polishes use such fine abrasives and are so accurate at leveling the paint that much of the risk associated with polishing paint has been reduced. But always remember that it is best to err to the side of caution and live with a few defects then thin the paint chasing perfection, particularly on a daily driver.
Re: How thick is your paint compared to common items: Pictures and Writeup.
Wow, amazing information and pictorial description Todd. When you put it in those terms it makes so much sense to save every little bit of clear coat we have and always go with the least aggressive method. It also makes product like Opti-Coat look like necessity on Daily driver.
Re: How thick is your paint compared to common items: Pictures and Writeup.
Todd,
Nice review and great photos! :bigups
I think these meters are amazing and their ability to measure thicknesses accurately is equally impressive especially if they`re repeatable.
Knowing just how much clear you have to work with is vitally important and is the difference between a successful detail or a trip to the paint shop..
Most of these meters work only with ferrous metals and they read only the total film thickness not individual film thickness; primer, sealer, color, and clear.
Will the meter you used measure individual film thicknesses?
Re: How thick is your paint compared to common items: Pictures and Writeup.
On mine it`s a very thin coat of paint and hard as nails.
Re: How thick is your paint compared to common items: Pictures and Writeup.
Quote:
Originally Posted by
TroyScherer
Wow, amazing information and pictorial description Todd. When you put it in those terms it makes so much sense to save every little bit of clear coat we have and always go with the least aggressive method. It also makes product like Opti-Coat look like necessity on Daily driver.
Thanks Troy. I believe it also shows how precise the abrasives we are using into the light as well.
Quote:
Originally Posted by
Concours.John
Very nice comparison!
Thanks John!
Quote:
Originally Posted by
Rocket
Nice post Todd. I never really knew how thick a mill was until my friend and I were talking at his shop. He does powder coating and everything he does he measures in mills. He even uses a nice paint gauge for his work.
I believe, in general, powder coating lays much thicker than a typical paint job. IRCC one lay over powder coat (in general) will range from 3 mils to 4 mils.
Quote:
Originally Posted by
BobbyG
Todd,
Nice review and great photos! :bigups
I think these meters are amazing and their ability to measure thicknesses accurately is equally impressive especially if they`re repeatable.
Knowing just how much clear you have to work with is vitally important and is the difference between a successful detail or a trip to the paint shop..
Most of these meters work only with ferrous metals and they read only the total film thickness not individual film thickness; primer, sealer, color, and clear.
Will the meter you used measure individual film thicknesses?
Thanks Bobby. The meter used will only measure total film thickness. I am unaware of any magnetic gauge (used for metals) that can measure individual layers, although they may exist. Generally layer thickness can only be measured using ultra-sound which (to my knowledge) only works on composites.
Re: How thick is your paint compared to common items: Pictures and Writeup.
Quote:
Originally Posted by
zoomzoom mazda5
On mine it`s a very thin coat of paint and hard as nails.
Not surprising Angelo. The total thickness on my Mazdaspeed 3 is 3.2-3.5 mils (total!). There is nothing on them :(
Re: How thick is your paint compared to common items: Pictures and Writeup.
Re: How thick is your paint compared to common items: Pictures and Writeup.
Begs a question.
How many "mils" will a typical correction remove?
Obviously, an aggressive polish will remove more than a finishing polish but how much?
Re: How thick is your paint compared to common items: Pictures and Writeup.
Quote:
Originally Posted by
Todd Helme
Man, you need to buff that table, I see severe swirl marks =D
Re: How thick is your paint compared to common items: Pictures and Writeup.
Thanks for taking the time very interesting.
Re: How thick is your paint compared to common items: Pictures and Writeup.
Quote:
Originally Posted by
Jeff U
Begs a question.
How many "mils" will a typical correction remove?
Obviously, an aggressive polish will remove more than a finishing polish but how much?
It`s so hard to say. Even if we knew the technique being used, the type (and hardness of the paint), the machine, the age of the paint, the surface area of the scratches, and every other variable, the only way to know for sure would be to test it and measure it before/after.
But I think you would be surprised how little paint is being removed in most circumstances. I two stage wet sanded, compound multiple times, polished, and final polished a new Ferrari and saw an average of .2-.3 mils difference. With careful polishing and realistic expectations you can polish your car many many times with out worrying.
Re: How thick is your paint compared to common items: Pictures and Writeup.
so a two wet sanding process (with proper technique and care)
will result on an average thickness of a sandwich bag....
Surprising!!!!!
Great Study Maestro!!!!!!
and cool :rockon !!!!!(I`ve missed that gentlemen)
Re: How thick is your paint compared to common items: Pictures and Writeup.
Here is a Defelsko meter that measures 3 layers and shows a graph - PosiTector 200 - Ultrasonic coating thickness gage measures coating over concrete, wood, composite and more. Conforms to ASTM D6132 and ISO 2808 and SSPC PA9
Its not cheap - right at $2700.00 Let`s see, how many Details will it take go buy one????? :)
Dan F
