Lets discuss paint thickness gauges

[Tex Star Detail]

OK, Ido not have one, and I keep reading about them. Thickness here,,,thickness there.
To MY understanding, I could be wrong, but these DO NOT gove you thickness of clear coatm but primer, base, and clear together.
So here comes my question (bet you didn't see it coming...LOL)
How in the world can you tell with a gauge, that the clear coat is thin or not. Don't you need to know specifics about the model or brand of car? What I mean by that is, what thickness, primer, base, and clear that type lf car has?

I know if it reads tremendously high, it is a repaint, but what about if it was thin?

How could you tell if the primer and paint were on thin and the CC thick, or vise versa? Is it just a tool that is over rated?

OR........is there a rough estimate on how much thickness is on a car? And you can remove X amount (which would be less than the clear itself) without worrying about burn through?

I dunno, maybe there is something I am missing about the whole paint thickness topic. Some insight would be great!

 

[Brenton]

Well...here's my two cents (2.3 cents in American currency).

Knowing whether a car is repainted tells a lot. It tells you about the quality of the paint, i.e., why does it need to be reconditioned now? What can you do?
You can save a lot of frustration in not being able to bring bad paint back, when it wasn't 100% to begin with. And you can save customers from being angry with you when your great polishing and wax look like crap in six months.
The guage will tell you the quality of the refinishing too. If it is 13 mils, you know they slapped it on thick and gooey and probably didn't prep the original surface right.
About clear coat? In my (perhaps not extensive) experience, clear coat thickness on a repaint is not the problem. There is often lots of clear. Good refinishers do it well, and you can recondition with about 80% of the confidence of OEM. Poor refinishers use clear to cover up a multitude of sins. If it isn't perfect, give it more depth with more clear and move on. So the 1:2 (or whatever) b:c ratio gets skewed to 1:3 or more.
Or much more.

It seems to me the concern for repaints is not clear thickness but quality, specifically:
1. Softness-hardness. Burning through twice the depth is not hard when your clear is not 100%.
2. Imperfections hidden between clear layers.
3. Orange peel, fish eyes, oxidization, etc.
4. A reconditioning that may only have 1/2 or 1/4 the life of an OEM detail job.
5. Customers that blame you for the quality of their repaint.

Do I have a guage? No.
Would I get one? Absolutely, but not for polishing--unless I found a used one at a yard sale. I offer a chemical that cuts and doesn't react well to poor repaints.

I think unless a paint shop goes on auction and you can grab a $600 guage for $150 or buy an $80 magnetic guage, I'm not sure a small detail operation can make back the money on their guage for what it tells them. There are other signs:
1. Orange peel, fish eyes, premature oxidization (especially on cars in the blue-green, ie, non red-black-white family), flecks, drips, etc..
2. Paint on trim, missing logos, etc.
3. Severe overspray in patterns (often sharp edged) where it slipped under the plastic; overspray on glass, lights, etc.
4. Colour change between panels.
5. Blending marks (looks like hazing).
6. Depth issues--either too much (extra clear) or a flat look).
7. A lack of metallics--almost every colour has metallic now, but some repaints don't.
8. Misaligned panels.

Good luck.
brenton

 

[Dans Detailing]

Well...here's my two cents (2.3 cents in American currency).

Knowing whether a car is repainted tells a lot. It tells you about the quality of the paint, i.e., why does it need to be reconditioned now? What can you do?
You can save a lot of frustration in not being able to bring bad paint back, when it wasn't 100% to begin with. And you can save customers from being angry with you when your great polishing and wax look like crap in six months.
The guage will tell you the quality of the refinishing too. If it is 13 mils, you know they slapped it on thick and gooey and probably didn't prep the original surface right.
About clear coat? In my (perhaps not extensive) experience, clear coat thickness on a repaint is not the problem. There is often lots of clear. Good refinishers do it well, and you can recondition with about 80% of the confidence of OEM. Poor refinishers use clear to cover up a multitude of sins. If it isn't perfect, give it more depth with more clear and move on. So the 1:2 (or whatever) b:c ratio gets skewed to 1:3 or more.
Or much more.

It seems to me the concern for repaints is not clear thickness but quality, specifically:
1. Softness-hardness. Burning through twice the depth is not hard when your clear is not 100%.
2. Imperfections hidden between clear layers.
3. Orange peel, fish eyes, oxidization, etc.
4. A reconditioning that may only have 1/2 or 1/4 the life of an OEM detail job.
5. Customers that blame you for the quality of their repaint.

Do I have a guage? No.
Would I get one? Absolutely, but not for polishing--unless I found a used one at a yard sale. I offer a chemical that cuts and doesn't react well to poor repaints.

I think unless a paint shop goes on auction and you can grab a $600 guage for $150 or buy an $80 magnetic guage, I'm not sure a small detail operation can make back the money on their guage for what it tells them. There are other signs:
1. Orange peel, fish eyes, premature oxidization (especially on cars in the blue-green, ie, non red-black-white family), flecks, drips, etc..
2. Paint on trim, missing logos, etc.
3. Severe overspray in patterns (often sharp edged) where it slipped under the plastic; overspray on glass, lights, etc.
4. Colour change between panels.
5. Blending marks (looks like hazing).
6. Depth issues--either too much (extra clear) or a flat look).
7. A lack of metallics--almost every colour has metallic now, but some repaints don't.
8. Misaligned panels.

Good luck.
brenton

thank you, this is what I was attempting to communicate in another topic. I can usually judge the paint "by eye" with the above mentioned 8 steps. If that doesn;t work, actually starting on the painted surface with a medium to light cut will tell you the entire story abotu the paint in a matter of seconds. I have never ruined paint before, and I ALWAYS use a high speed buffer.

I have both style gauges, the magnetic one is not as usefull due to the fact that it doesn;t work on composite cas, so if you buy one buy an electronic one.