paint blemish - buffing options?

[prkaye]

I was filling my tanks with auto gas yesterday. Some of the fuel slopped on the wing and sat there for a few minutes. It has left a cloudy white blemish in the paint. I'm hoping it will buff out. A few years ago, within a couple of weeks of getting my plane painted, some avgas left a blue stain in the paint. The painter loaned me his orbital buffer and some special buffing compound that got rid of the blue stain. I'd like to try something similar this time.
Any recommendations for product or technique to buff out this blemish?

[Skid]

I would try using a clay bar on it first. They are available in most auto parts stores (Autozone, etc). I use Mothers brand but there are others.

[prkaye]

Thanks, great tip. I'll try that first... clay bar and McGuire's instant detailer.

[flyingriki]

Clay works best on bumpy contaminants. But l'd like to hear if it does any good. Your buffing idea seems like the best approach but I bet Dan can advise you better. I think he knows paint....!

[prkaye]

the clay and detailer didn't do anything. Even polish with an orbital polisher didn't do much. I then used Nu Finish Scratch doctor (basically an aggressive polish, I think), with a microfiber cloth and a tonne of elbow grease (many iterations, and a lot of pressure and speed), and I got the blemish to the point where you can only see it when the light hits at just the right angle. Not perfect, but vastly improved. Lesson learned... fuel can damage paint.. be careful and wipe up spills immediately!

[flyingriki]

Phil, do you know what brand of paint it is?
Would still like to hear Dan's take on the damage.
PS: my fueling pack with the drain tool to open my caps is a hand size towel to lay next the hole and keep the cap and fueling hose off the wing. Also good for wiping up spills immediately.

[DanH]

Any kind of cutting compound should work.

Curious about the paint. Fuel shouldn't damage paint. For sure it doesn't bother PPG DCU2021 clear, because I'm the sloppiest fuel guy on planet earth.

[prkaye]

Dupont Aviation Imron.

I've slopped lots of fuel on it over the years without incident. So I can't say for certain that this time it was the fuel (Shell V-Power) that caused the problem. But the timing of my noticing the cloudy blemish coincides with fueling up, and I know I slopped a bunch and left it to sit for 15 or 20 min while it was fuelling, so there's strong circumstantial evidence.

Question - I've been polishing that area with a LOT Of pressure using that Nu Finish Scratch Doctor stuff. My concern is, how far can I go with this before I start to rub through or begin to significantly damange the paint finish itself? I've got it now so that the blemish is only noticeable if you look carefully and with the light reflecting off it at a very specific angle. I'm not sure whether I should cut my losses and leave it as-is now, for fear of over-polishing. Is this possible?

[DanH]

Originally Posted by prkaye

Dupont Aviation Imron.

I've slopped lots of fuel on it over the years without incident. So I can't say for certain that this time it was the fuel (Shell V-Power) that caused the problem.

Ahhh, auto gas?

I'm not sure whether I should cut my losses and leave it as-is now, for fear of over-polishing. Is this possible?

Yes it is. With any kind of abrasive polish, you're removing paint thickness. Eventually you'll cut all the way through, or at least enough to start seeing the primer. Car dealers got into this problem a lot back in the 90's, as 80's vintage paints didn't have very good UV resistance. We would start buffing off the dead paint, and sometimes found it extended all the way through the color coat....

[prkaye]

Yep, auto gas.
Ok, good to know about over-polishing. I'll leave it as it is now.