I had a little bit of time after work today before it got too dark. I would polish inside but it is way too messy so weather permitting I will try to make some real progress this weekend. Polishing aluminum is a multiple step process, but just for a teaser I went over a couple feet with some white coloring compound.
The problem with extruded aluminum is that it has a grain to it. If you just polish it like it is, it will have a orange peel type texture to it. It will be shiny and fairly reflective, but my selective OCD will not allow that grain to stay. To buff it out I will first have to go over it with a brown (tripoli) compound. It "cuts" better than white. Hopefully I can get most of the grain out with that. If I can't I may do some wet sanding starting at 1000 grit or so, then buff it. Since brown leaves a hazy finish you have to go over it again with white to brighten it up. Then I will have get out all the very fine scratches left by the buffing wheel (in this case a vented, untreated 8" cotton buff). I will probably just use some Fritz, a microfiber towel and some elbow grease, but this may be the hardest step. But tomorrow I will get you all some pics of my equipment and setup and try to make some progress. It will be cold (45F) and cloudy/rainy all day so don't be too disappointed if I don't get much done.