Hey all, in one of the boat forums I belong to, someone said they used GOJO pumice hand cleaner as an aluminum polish all the time. Since I needed some anyway for working on my greasy old van, I tried it on my grandfather's '55-or-so Grumman boat (which I'm pretty sure has never had anything other than hose rinses in its lifetime). This is about half an hour's elbow grease with an old t-shirt on the dinged-up bottom, and a quick rinsing (man it's hot out there standing over that solar oven of a boat). I wouldn't use it on skins because it does scratch, but for a first cleaning on window frames and j-rail I think it will work pretty well. It's wet and slippery, it doesn't have the sticky friction of say, wiping off car wax, so you don't have to rub very hard, and the corrosion comes right off. I'm going to try it on my window frames with a cloth buffing wheel on my drill.