Clearcoat failure

[efnfast]

I see 80microns being tossed around on here quite frequently as the place where most people stop serious corrections.



If a car has, say, 115 from the factory, 80 is only a 30% reduction in clear, so why would going below that cause potential failure?



Does clearcoat need an absolute minimum amount (e.g., 80microns) of film to be present for protection, otherwise it fails in the UV?

 

[Dan]

That's saying most cars have 115 microns of clear. Most new cars are around 100-130ish total.

 

[GS4_Fiend]

So how many microns would be a failure to UV?

 

[mikenap]

I see 80microns being tossed around on here quite frequently as the place where most people stop serious corrections.



If a car has, say, 115 from the factory, 80 is only a 30% reduction in clear, so why would going below that cause potential failure?



Does clearcoat need an absolute minimum amount (e.g., 80microns) of film to be present for protection, otherwise it fails in the UV?

I was under the impression that the 115ish number was primer, base and clear together. Am I wrong in this?

 

[efnfast]

So how many microns would be a failure to UV?

Personally, I don't think most know. In my searching I've never found something that says you need XXmicrons of clear as an absolute minimum; any less and UV damage occurs, clear fails, and it's time for a repaint. Obviously the lower the number the dicier it gets, but I've come to think that when people talk about readings they're just trying to sound like they "know" what they mean.

 

[Darkstar752]

Clear coat only makes up a portion of the paint, and a PTG measures the amount of paint, not the amount of clear.



80-90 is the area where you probably don't want to polish the paint at all, because most of the reading is primer and the color coat, and there is barely any clear left on the panel.

 

[GS4_Fiend]

i got a reading of 1.5 Mils on my hood.

 

[GS4_Fiend]

I found the problem. I put it back to factory restore and the meter is back to normal. My hood reads 4.5 Mils. I totally eased out now. Thanks for the help.

 

[Dan]

The trick is finding a spot that hasn't been buffed if you don't know the history on it. On some cars the door jambs can give you a clue. On other cars you might be able to get the paint meter in between an emblem. Then do your math from there.

 

[David Fermani]

Personally, I don't think most know. In my searching I've never found something that says you need XXmicrons of clear as an absolute minimum; any less and UV damage occurs, clear fails, and it's time for a repaint. Obviously the lower the number the dicier it gets, but I've come to think that when people talk about readings they're just trying to sound like they "know" what they mean.

Balls on brother!!! :2thumbs:



I see a few here post Click N Brags of paint thickness readouts with their high dollar PTG and they're only doing light polishing? Whatever makes them feel like they're special I guess.



The only benefit of a PTG is to see how much total film build is on a specific spot on a panel and to measure any deviation after correction.

 

[Dan]

Balls on brother!!! :2thumbs:



I see a few here post Click N Brags of paint thickness readouts with their high dollar PTG and they're only doing light polishing? Whatever makes them feel like they're special I guess.



The only benefit of a PTG is to see how much total film build is on a specific spot on a panel and to measure any deviation after correction.

Well, I guess there is the talk, and then the specific recommendations by several paint or car mfgs as to how much clear can be removed. Are those absolutes? No, but its better than guessing.

 

[David Fermani]

Sure, anytime you can baseline the total thickness of your paint, it's better than being blind when doing a heavy correction. Obviously, it's only just a guestimate really unless we could break down each coating.

 

[Dan]

Sure, anytime you can baseline the total thickness of your paint, it's better than being blind when doing a heavy correction. Obviously, it's only just a guestimate really unless we could break down each coating.

Plus if you do this for a living, that $200 highline gives you WAY more street cred than the geek squad detailer who has nada

 

[carcat1]

Plus if you do this for a living, that $200 highline gives you WAY more street cred than the geek squad detailer who has nada

That's a funny way to put it, yakky.



Street cred is always good. More importantly, if you are a detailer who does a lot of paint correction projects, the cost of avoiding mistakes will more than pay for a budget paint meter like this.



In fact, if you work on luxury cars, the cost of avoiding mistakes on that would more than pay for a premium-grade paint meter like an Elcometer or Defelsko.