Single stage paint got lighter after correcting it?

I originally posted this to Reddit, but the only response I got was Mike's insanely helpful guide to single stage paint. I want to understand why my single stage paint got lighter after correcting it.

I'm learning to paint correct on my 98 Lexus ES300. It's classic green pearl, which is single stage. I've done the hood, roof and trunk, all of which are a the result 10 year old cheap Maaco job. Up until today, I was only doing a single pass (once left to right, once up and down), and as a result wondering why I still had a decent amount of scratches despite compounding and polishing. I found Mike's video tutorial on how to paint correct, and saw that he was doing 8 passes.


My first test spots were on the hood, the paint got lighter after I stepped up the aggressiveness. I decided the best strategy was to do one compounding and one polishing pass and moved on to trunk and roof. After learning that I could do more passes, I tested out the roof (which I had already compounded + polished 1 pass each) by polishing with 4 more passes to see the difference. I got the results I was looking for, and went back to experiment with the hood.

This time, I did three passes while compounding, and 3 passes polishing. This definitely removed more scratches, but also removed the much of the dark green color, causing the area to look dull. You can see the results below, the area in the top right is my original test spot. Apologies if the image isn't clear, it's my first time posting. I've got photos up on imgur as well if that helps, the link is https://imgur.com/a/YBPuzr2.

Attachment 72222































I understand how 2 stage paint jobs work and have tried correcting panels on another car (albeit using 2 total passes each), but I am confused as to why the paint got lighter when I feel like I didn't even cut through that much paint. I thought that single stage paint was paint + clear coat in one substance, and that unless you had metallic paint which has flakes in it, the substance should have a consistent amount of paint and clear coat. Does pearl single stage work differently than normal? Or is this a function of how the area was repainted, like a lighter green coat laid down and then a darker green on top?


I'm not too bummed about it, as it isn't original paint and I am perfectly fine experimenting with it, though seeing how bad it looks on screen in wish I could fix it.

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Originally Posted by ferozen

I originally posted this to Reddit, but the only response I got was Mike's insanely helpful guide to single stage paint. I want to understand why my single stage paint got lighter after correcting it.

I'm learning to paint correct on my 98 Lexus ES300. It's classic green pearl, which is single stage. I've done the hood, roof and trunk, all of which are a the result 10 year old cheap Maaco job. Up until today, I was only doing a single pass (once left to right, once up and down), and as a result wondering why I still had a decent amount of scratches despite compounding and polishing. I found Mike's video tutorial on how to paint correct, and saw that he was doing 8 passes.


My first test spots were on the hood, the paint got lighter after I stepped up the aggressiveness. I decided the best strategy was to do one compounding and one polishing pass and moved on to trunk and roof. After learning that I could do more passes, I tested out the roof (which I had already compounded + polished 1 pass each) by polishing with 4 more passes to see the difference. I got the results I was looking for, and went back to experiment with the hood.

This time, I did three passes while compounding, and 3 passes polishing. This definitely removed more scratches, but also removed the much of the dark green color, causing the area to look dull. You can see the results below, the area in the top right is my original test spot. Apologies if the image isn't clear, it's my first time posting. I've got photos up on imgur as well if that helps, the link is Mistakes were made - Album on Imgur.

Attachment 72222




























I understand how 2 stage paint jobs work and have tried correcting panels on another car (albeit using 2 total passes each), but I am confused as to why the paint got lighter when I feel like I didn't even cut through that much paint. I thought that single stage paint was paint + clear coat in one substance, and that unless you had metallic paint which has flakes in it, the substance should have a consistent amount of paint and clear coat. Does pearl single stage work differently than normal? Or is this a function of how the area was repainted, like a lighter green coat laid down and then a darker green on top?


I'm not too bummed about it, as it isn't original paint and I am perfectly fine experimenting with it, though seeing how bad it looks on screen in wish I could fix it.

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Here's my opinion...

What I can gather from your description of the paint job and the color is that the paint is some type of single stage metallic. I know you said the color is "classic green pearl" but that is only a name for the color, not necessarily an indication that it is a true pearlescent. I don't know of any "true" pearlescents that are not a three step paint processes, i.e., base coat/pearl coat/clear coat.

But for the sake of this discussion, and assuming that your single-stage color does actually have some pearlescent pigments in it, lets just consider those pigments in the same category as the metallic particles in a single-stage metallic color.

What is causing your color shift (lighter/duller as you have described) is one of two things...

1) The compound you used has scoured the surface resulting in the "dull" finish you describe. And then your polishing step was not aggressive enough, or thorough enough, to remove the scouring.

Note that at this point of your test process you should have stopped to assess what you might do differently to achieve a better result before proceeding onto the the roof and deck lid, but that is water under the bridge now.

2) The "lighter" color you describe can be either a combination of, or either individually, the dulling effect addressed above or the disruption of the metallic orientation as a result of your polishing. Whenever you polish a single-stage metallic color you are altering the relationship of the metallic particles relative to the paint's surface. As the metallic particles become closer to, or exposed to, the paint's surface the color will appear lighter.

This altering of the metallic particles orientation is why I describe polishing single-stage metallic colors as a risky endeavor. See post #7 in the following thread for a more detailed explanation... Dark spot in paint after wet and dry

As for your next step to try to improve upon what you have... If it was me I'd be going at it with multiple passes using a fine cut polish. That should improve upon condition 1) above. If condition 2) more accurately describes the actual condition, then there's really nothing that can be done.

A few other points...

You said you re-polished the roof and were happy with the results. You should have simply repeated that process to the hood and the rest of the car instead of re-experimenting on the hood. If the roof was any indication then there was no need to compound the hood. It should have been polished just like the roof.

Single-stage paint is not color plus clear all in one. It is color pigments held together with some binders/resins, but those binders and resins are not the same as clear-coat used in a modern BC/CC finish. To say single-stage is color and clear all in one is somewhat of a misrepresentation of what it actually is. Single-stage paint is just that... A single-stage paint that does not require any clear coat.

Thank you for the information, this is all really helpful! I feel like 2 is probably the case, but I will try polishing it to see if I can improve it at all.

The reason I went more aggressive on the hood is because the area had deeper scratches and swirling than what was on the roof. I was curious to see if by using the new technique I could get those out.

My testing method was also pretty flawed, instead of moving to a second test spot and attempting a more aggressive method, I went over the original test spot (where I had polished initially) with compound. Like you said, what's done is done, but again I'm happy this happened on paint that I'm not super concerned about.

Sorry if this is a noob question, but should I be using a different pad when I use a fine cut polish? I have a white lake country foam pad, and am planning to use Megs M2 for the polish.

I've never used either that pad or that polish so I really can't comment... Except...

I did Google M2 and see that is a diminishing abrasive technology (DAT) formula. I think you may be better served with a super micro abrasive technology (SMAT) formula, i.e., M205 or M210 as they work more consistently throughout the polishing process.