Importing this old post just for reference - and expanding on it a little.
[2018 Aside and a very little bit of history: The Custom Classic is a full mech squonker made in the USA. And no, this is not a Coppervape. Just getting that out of the way . The Custom Classic was based on pdib's mods (with pdib's blessing), but is not a 1:1 cone and is in metal rather than wood. The Coppervape was later based on the Custom Classic - in the early pictures on their web site, they actually used pictures of genuine Custom Classics, but the final Coppervape was not a 1:1 clone.]
The aluminium has a tendency - for some people/in some climates? - to tarnish where there is skin contact, leaving dark, dirty-looking areas.
At this stage it's something like 5 weeks since I did anything other than occasionally wipe the CC over with a damp cloth. I take this mod everywhere - it had multiple fine scratches and you can clearly see where my fingers rest near the squonk hole:
The first step is to use grey Scotchbrite pads (ultra-fine 7448) to refinish the brushed surface and remove those fine scratches. The grey pad sheds very fine grit, so put it on paper towelling and then then move the mod across it, always moving in the same direction as the original brushed finished.
[2018 update: These days it's a titanium Custom Classic that I take everywhere. Of course the Ti doesn't tarnish, but it does get fine scratches which I occasionally remove with a slightly coarser pad: maroon Scotchbrite pads (very fine 7447). There are other brands such as Bear-Tex with similar grades of Ultra Fine and Very Fine pads.]
It's looking better already:
Now it's time to get out the Simichrome polish (bought mine from Amazon, but they now say it doesn't ship to Australia) and start adding a bit of shine.
[2018 update: There are many other metal polishes that can be used - Autosol is just one example. All are at least mildly abrasive. If you polish and then find the finish is too shiny, you can always use the hand pads again to restore that brushed look.]
For that special finishing touch, some Renaissance wax for a real shine, and finally a fresh wick and a dab of something (NO-OX-ID "A Special" in my case) where the lid meets the body etc.
And now I feel as though I should have invested in white cotton gloves:
The Ti is fabulous. It's a pity Corey's not making them any more. I'm going to send mine back to him some time this year for a spa bath treatment. It's been dropped multiple times, and it's used so much (all day every day for 18 months) that the magnets in the lid are looking a bit scungy. Still fires beautifully, but needs a pretty-up. I can live without it while it's at the spa because I have two Ti's