Need Advice from Paint Experts

[Seadweller]

Greetings!

As a teen, I used to work with a guy doing full resto's on 50's Thunderbirds, but over that time, never worked with metallic paints. My Boxster is Ocean Jade Metallic, and I have a small scratch on the poly bumper that I'd like to repair. I've attempted the repair 3 times, and every time the end result is a silver fill.

I'm using the Porsche touch-up paint, and I've tried the Langka system, wet sanding/polishing, and the "card swipe" method, and all 3 have yielded the same end result. Is this a case where I have to somehow fill the scratch and level it as best I can while skipping the final step? Problem is, the repair looks pretty bad if I don't level and polish it. I'm puzzled.

[blue62]

Originally Posted by Seadweller

Greetings!

As a teen, I used to work with a guy doing full resto's on 50's Thunderbirds, but over that time, never worked with metallic paints. My Boxster is Ocean Jade Metallic, and I have a small scratch on the poly bumper that I'd like to repair. I've attempted the repair 3 times, and every time the end result is a silver fill.

I'm using the Porsche touch-up paint, and I've tried the Langka system, wet sanding/polishing, and the "card swipe" method, and all 3 have yielded the same end result. Is this a case where I have to somehow fill the scratch and level it as best I can while skipping the final step? Problem is, the repair looks pretty bad if I don't level and polish it. I'm puzzled.

I am "NOT" a paint expert but:
Wet sanding does not work on single stage or base coats of a metallic paint.
Your sanding the metal flakes themselves and changing the way the light reflects off of them. If your going to wet sand it has to be the clear coat only on a two stage system paint. When you "card swipe" your changing the orientation of the metal flakes. Again changing the way the light reflects off of them. Google wet sanding metal flake paint. lots of info.

[Seadweller]

Originally Posted by blue62

I am "NOT" a paint expert but:
Wet sanding does not work on single stage or base coats of a metallic paint.
Your sanding the metal flakes themselves and changing the way the light reflects off of them. If your going to wet sand it has to be the clear coat only on a two stage system paint. When you "card swipe" your changing the orientation of the metal flakes. Again changing the way the light reflects off of them. Google wet sanding metal flake paint. lots of info.

Thanks...I suspected that might be the case. So essentially, I'll have to fill the scratch below grade, add a clear, and then sand/polish the clear to level? If I get the metallic fill above level and clear coat it, I assume I'll sand/polish through the clear and into the paint, yielding the same result.

[blue62]

Originally Posted by Seadweller

Thanks...I suspected that might be the case. So essentially, I'll have to fill the scratch below grade, add a clear, and then sand/polish the clear to level? If I get the metallic fill above level and clear coat it, I assume I'll sand/polish through the clear and into the paint, yielding the same result.

You would have to "feather sand" the clear around the scratch without going into the base coat (metallic). If you do it by just filling the scratch area the clear will most likely peel or lift off in a short time. This is true of any base coat clear coat system. Also if the touch up paint has more or less metal flake in it then the original paint it will reflect light differently then the original paint. so it will still look odd.
Metallic is a hard paint to repair when damaged. Very Very difficult to match just because of light refraction from the metal flake.

Again I am "NOT" an expert just a hobbyist with my own cars.