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oledude
04-27-2007, 11:38 AM
First, I am a newbie to painting. I recently purchased all the gear and such from Len, and did a first project. I painted a damaged bumper on 2000 Mustang. For the most part the painting part went well, after playing / learning about the new tools and such. I used PPG Omni AU basecoat (Black) with Omni Clear Coat. I know you should use family of products, but used Duplicolor plastic adhesion primer under the basecoat.

After finishing the Clear Coat in the initial drying period, I noticed a brown tint in the repaired area. It appears to be under the Clear Coat and limited to the basic repair area, not in blended area. Several days have passed, and the brown tint is fading somewhat but still visible.

I have not done any sanding, compounding, etc, at this point.

What might be the reason for the color change, using a non-family product like Duplicolor with the PPG product? Thanks

Dork
04-27-2007, 12:01 PM
Did you use any gray primer or sealer under the basecoat? Black will look brown if it is still transparent and not covered completely. Being that you say it only looks brown on the repaired area and not where you blended, I would say that it is not covered and you need to repaint.

oledude
04-27-2007, 12:40 PM
I used the Duplicolor plastic adhesion primer which was clear. That may be the issue. If I repaint, I plan to use the Omni PGG family primer which I beleive is gray in color.

I just checked the repair area again in bright sunlight and see the hole repair area which did have a filler, does not show brown, and the area that does still show the brown tint was painted over existing basecoat. Not sure if that would change the need for a primer or if using the Duplicolor product caused the issue.

Lucky the area is small and easy to just repaint. Oh, the life of a newbie....

Phil V
04-27-2007, 04:14 PM
I'm all for saving a buck where applicable but in most cases that would not include skimping on basecoat quality. If you had used PPG DBU with its reactive reducer you would not be having any problems. (I don't mean that in a smart assed way, just a simple fact).

Another thing to consider is that there are many different tints of black. 30 years ago there was only one automotive black. Didn't matter if it was VW beetle or a Cadillac we used only one black. Thats most definately is not the case now. For the most part there are currently two basic blacks for American automobiles. Ford and Chrysler use whats referred to as 9700 black which is a black black while GM uses the 9400 black which is a black with a brownish tint.

Len
04-27-2007, 08:22 PM
Phil is right! Make sure you have the black that matches your car's color code. Black can be bluish, grayish, brownish etc.

dixie1776
04-27-2007, 09:16 PM
what has happened in your case is that your repaired area wasn't sealed enough, thus soaking up the base coat, this caused a slight light looking spot, which won't go away unless repainted.

oledude
04-27-2007, 09:16 PM
Thanks for the information. The basecoat was matched to the paint code on the door, which was AU. I understand the thought about quality, and one reason for using PPG line. The Omni line is not the top of the line, I did understand that when purchasing. I will try again and post the results, using a compatible primer.

DougMN
04-27-2007, 10:26 PM
I have heard that omni black will come out brown.