Thanks for the compliments. I'm pretty excited to finish the build now.
The haziest section is actually the hood, but that's mostly a function of how the car is viewed and/or the last time a section was polished. The hood and left side were polished first, so they are oxidized more than the back and right side. There are several coats of wax over the polished surface to slow oxidation, but it will slowly lose its shine. There are many little imperfections, but overall, I'm really content with it and can always buff it with a little Mother's and wax to clean, now that the hard work is done.
So...here's my polishing process...i.e., the hard work:
First, I read about every article I could find on polishing aluminum and converged on a process that's a hybrid of several methods, after trying many approaches.
To smooth the surface, I wet sanded with 1500 grit against the grain of the aluminum until only cross-grain scratches were visible. Following the 1500 grit, the car was wet sanded with 2000 grit, with the grain, until the 1500 grit marks were all but gone. I lightly sanded a few small sections of the car with heavier grit to remove deeper scratches, before moving to the fine grit papers. All sanding was performed with a soft foam block.
After sanding, I hand polished (fearful of the power buffer) using Mother's polish, in areas of about a 1 square foot at a time. I tried many different cloths and converged on generic auto parts store microfiber, after talking with a Mother's sales rep at the Long Beach Grand Prix. Cotton of any form left far too many scratches and swirl marks. After polishing several square feet to a bright shine using a somewhat random polishing method, I went back over the area with Mother’s, with the grain of the aluminum, using very light pressure. This last step masked the random swirl marks with small linear scratches that blend with the grain of the aluminum. After polishing a section, the area was coated lightly with paste wax, also applied with microfiber.
Needless to say, it took a long time.
The engine I am starting to build is a 1700cc crossflow, with forged pistons and rods, an A6 cam, and an SCCA crank. Once the bottom end is together, I’ll start saving for a head.
I’ll add more pictures are the project progresses.
Thanks again for your compliments on the polishing,
Dave