Paint thickness

[MDC250]

Bit of a nerdy question but hoping someone can help...

Appreciate every model, down to individual car and even panel can and invariably will have varying depth of paint but...for those that have either got and use a PTG or any pros out there with v expensive PTGs ballpark what kind of thickness of paint would you expect on a 12 plate S204?

I'm led to understand as a rule of thumb work on thirds as in base, colour, lacquer in equal measure and to take no more than 25% of top coat over lifetime of paint correction. So for example overall thickness of 120 microns, lacquer is say 40 microns giving me 10 microns to play with in terms of correction.

Thanks in advance.

 

[J LAD]

Yep your not far off here.
For a quick round up 25 micron = 1 thousand of an inch ( 1 thou ) in old money.
As you say all cars and all panels will vary, but on the whole a car with metallic paint and top coat lacquer should in total measure anywhere between 120 micron up to 160 micron plus, 4 TO 6 THOU.
Normally the clear coat makes up 50 micron of this thickness, ( 2 thou )
If you are doing any kind of WET SANDING or HEAVY CUT CORRECTION you must take paint depth measuremnts.
Take Porsche for example, their steel panels easily see 120 micron, but i have seen their aluminium panels read only 80 micron in total ( 3 thou ish ).
If you are using a heavy cut compound polish with say a wool or coarse pad, expect to remove around 2 to 3 micron of clear coat.
Its the wet sanding using 1500, 2000, 2500, and 3000 grade paper thats most dangerous, as you have to machine polish the clearcoat back to a gloss finish, and you can easily remove too much clearcoat if you are not carefull.

 

[Silver CL55]

I know a guy who got the sack for being 3 THOU out......



Worked in a bank, boom boom!

 

[MDC250]

Think I've got the PTG calibrated now.

Few quick reads and ball park this is what I'm getting.

Sound about right?

Bonnet 104 NFe

Roof 140 Fe

Drivers door 150 Fe

OS passenger door 143 Fe

Rear panel 144 Fe

Boot 100-150 Fe? Thinner near badge

NS passenger door 150 Fe

NS door 160 Fe

 

[MWCLS]

Think I've got the PTG calibrated now.

Few quick reads and ball park this is what I'm getting.

Sound about right?

Bonnet 104 NFe

Roof 140 Fe

Drivers door 150 Fe

OS passenger door 143 Fe

Rear panel 144 Fe

Boot 100-150 Fe? Thinner near badge

NS passenger door 150 Fe

NS door 160 Fe

A friend of mine had a BMW M6 real garage queen, average PTG readings over the car 80 microns before he sold it.

 

[MDC250]

A friend of mine had a BMW M6 real garage queen, average PTG readings over the car 80 microns before he sold it.

As in he polished it to death or BMW paint is thin to start with?!

 

[MWCLS]

As in he polished it to death or BMW paint is thin to start with?!

He was the 2nd owner, so maybe the previous owner had gone crazy polishing, IIRC BMW is not thin, like all the others you get the orange peel thrown in for free.

Hence the need to polish or maybe a amateur attempt at wet sanding.

 

[Blue Moon]

Think I've got the PTG calibrated now.

Few quick reads and ball park this is what I'm getting.

Sound about right?

Bonnet 104 NFe

Roof 140 Fe

Drivers door 150 Fe

OS passenger door 143 Fe

Rear panel 144 Fe

Boot 100-150 Fe? Thinner near badge

NS passenger door 150 Fe

NS door 160 Fe

I'd wager the NS door and drivers door have been repainted, and the bonnet has had some 'paint correction' work on it.

I'm sorry, but if you haven't owned the car from new, all a PTG will do is tell you how thick the paint is now. So what ? It won't tell you how much paint it's had, or indeed how many times a 'detailing expert' has worked on it.

And having a new car is no guarantee it's not been re-painted before you get it anyway. Unless you're prepared for the consequence of burning through, which even professional experts do albeit rarely, pay for someone who is an professional to do it

 

[MDC250]

I'd wager the NS door and drivers door have been repainted, and the bonnet has had some 'paint correction' work on it. :

I was thinking no two panels would have the same thickness...weirdly though quickly went over the wife's Qashqai which is knocking on for 5 yrs old and give or take 4 microns it's consistent all over.

 

[Blue Moon]

I was thinking no two panels would have the same thickness...weirdly though quickly went over the wife's Qashqai which is knocking on for 5 yrs old and give or take 4 microns it's consistent all over.

That's because, unlike a bodyshop or any professional repair where human 'error' spray gun application can make the paint thicker / thinner simply be being applied for a second or two longer in a slow pass, or an inch or two closer, a new car is painted under computer controlled laboratory style conditions. Almost 100% consistency. So you get the same paint thickness and orange peel on every panel

If the car's not new, or you don't know it's 'paint' history, a PTG will give you information that's interesting but not a lot of use.

Just a tip, if you can catch your finger nail in a scratch, any scratch, it's very unlikely it will polish / sand out. It will almost certainly need painting

 

[Jonwatson]

I work in Nissan factory paintshop the car has a number of points on every panel where paint thickness is messured, if a result shows up an out of spec condition we have to alter computer data til it's right!

 

[MDC250]

I work in Nissan factory paintshop the car has a number of points on every panel where paint thickness is messured, if a result shows up an out of spec condition we have to alter computer data til it's right!

I'm mightily impressed as to the uniformity TBH, it's swirled like mad mind but again uniformly so!

 

[Jonwatson]

We just had new robots put in for spraying new infinity (A class underneath) where target is to be painted to within a couple of microns canny tough target I think u will agree

 

[MDC250]

We just had new robots put in for spraying new infinity (A class underneath) where target is to be painted to within a couple of microns canny tough target I think u will agree

Yup must be very difficult especially on any variation in shape/line.

Ideally I need to find a local paint shop/sprayer who has a multi layer PTG. I'm only a weekend warrior so can't justify the outlay!

I may however bite the bullet and book in for a lesson with a pro Detailer to get some accurate reads and make sure my correction rates are as minimal as they can be!

 

[Jonwatson]

http://youtu.be/UwoGsCAKsxU try watching this then for detailing

 

[J LAD]

MDC250,
I think you may be over worrying here my friend.
If its only the swirls you want to get rid of, then you will not remove any thickness of the clear coat at all, believe me.
As I said , really going for it with a coarse pad and fast cut polish, will only remove around 2 to 3 microns max!
After that you are simply burnishing and "jeweling" the paint / lacquer back to a high gloss finish, you will not remove any more clear coat.
Eg been at Porsche Sheffield all day, some very fine swirls and fine scratches on most panels after their valeters had washed her ( 911 GTS), single stage paint too.
2 passes with yellow pad and Menzerna medium cut polish, then 2 passes with black pad with Menzerna fine polish. Exactly same paint thickness as when I started!

 

[MDC250]

MDC250, I think you may be over worrying here my friend. If its only the swirls you want to get rid of, then you will not remove any thickness of the clear coat at all, believe me. As I said , really going for it with a coarse pad and fast cut polish, will only remove around 2 to 3 microns max! After that you are simply burnishing and "jeweling" the paint / lacquer back to a high gloss finish, you will not remove any more clear coat. Eg been at Porsche Sheffield all day, some very fine swirls and fine scratches on most panels after their valeters had washed her ( 911 GTS), single stage paint too. 2 passes with yellow pad and Menzerna medium cut polish, then 2 passes with black pad with Menzerna fine polish. Exactly same paint thickness as when I started!

Cheers, have a few options pad and polish wise so will see how I get on...less thinking more doing!

 

[Scooby_Doo]

Might be a stupid question, BUT - would the paint thickness on metallic finish be thicker than a solid colour or do they both get a top clearcoat applied.Main reason for question is that I've ordered a car in Polar White, first non metallic finished car I've bought in over 30 years. Noticed that the recent problem with Red Mercs is the laquer bubbling & peeling.