1975 BMW 2002 fresh Polaris silver paint (twice)

Earlier in the year I was on a strong roll whipping the body into shape and took the leap to paint the car myself. I have successfully painted before, albeit single stage. The BMW is getting a base/clear system. I have an inexpensive harbor freight HVLP gun and a good compressor. I set aside a complete Saturday for the project and set out early with two layers of a gray sealer, which when on respectably smooth and even. After the appropriate flash time I sprayed on three beautifully uniform coats of the base metallic silver "Polaris" color.  After enough flash time I mixed up the clear and started spraying. I immediately was having difficulty putting on a smooth coat of clear. It was spraying out in large drops/blobs. No matter how I fiddled with the gun, it wouldn't flow even and smooth. I reasoned that I could just lay it on heavy and cut/sand/polish it to a good smooth finish. It might have worked, but it didn't. The clear was so heavy that it hadn't time to flash off before it began to attack the base coat and wrinkle it in places. The following is how it all went down and what I did to move past this terrible "worst-case scenario" situation.

Little 2002, masked under awnings in the side yard wearing a fresh sealer primer coat

Gallon of Polaris base color, custom made by my local automotive paint supplier

Carefully spraying on the base so as to achieve uniformity, avoid any mottled panels or "tiger stripes"

When the base flashed off it had a low satin sheen and it looked almost good enough as-is. I was very pleased with the progress.

During my third pass with the clear is when I noticed the base-coat problem, so I immediately stopped spraying.

You can see the shine brought by the clear, and if not for the cracking, this would have been a fine home-job paint project.

But, this is the result in a few places. 95% of the car looked fine, but a few spots on the trunk, hood, tail panel and "C" pillar had this terrible reaction. It still makes me a little sick to my stomach to look at this.

I have no photos of what took place next- weeks of pain-staking, miserable careful re sanding of the entire body to remove all the failed clear and blend everything back together. Then I took the car to my local paint shop and paid up to have them shoot the car for me.

When I got the car back I masked off the edges and wet sanded with 2000 grit, followed by 3000 grit to really make it smooth, but dull

I spent a day buffing the shine back up.

I spent the next day putting these parts back on.

Some of the trim was looking very very faded by comparison to the new paint, so I polished and cleaned it up. This stuff made the lower moldings look great

Not a huge fan of the brand, but this stuff made the faded bumper bellows look good again (UPDATE: When refueling, I spilled a lil gas on the r/r bellows and it smears this stuff right off into a gooey black greasy mess that invariably ends up getting wiped onto the cars body.)

A little polish and 0000 steel wool cleaned up the marker chrome

the fine sanding and high-speed buffer turned the once bashed and faded drivers door into a mirror!

Coming together. In this photo I haven't yet installed new window rubbers or upper belt line trim, but they went on shortly after. I later discovered that my HVLP gun had a clogged passage near the tip. Had I properly cleaned it, this likely never would have happened. This was a hard lesson. 

Final iteration wearing all trim and in daily-driver shape

At the rear I removed the original license plate lights and added tiny LEDs to clean up the lines a bit.