Quote Originally Posted by Cornelius View Post
I haven't found a 'squirt on' solution that truly works. I use a quality metal polish (i.e. not brasso) that I found at Home Depot. I've always taken apart carts to use it, though one could maybe figure out how to make it work without.

For system connectors I've actually had really good luck with very fine grit sandpaper wrapped around a credit card, then a 'wash' with rubbing alcohol on cotton paper wrapped around a cc. The sandpaper I use I believe is usually used for first-pass sanding on auto paint.
If you've got the name of the metal polish I'd love to know

I've used sandpaper before as well on connectors, works pretty well. For carts I'll use rubbing alcohol + art eraser + very fine steel wool (only if it's very stubborn). Don't like using steel wool too much though since it's essentially filing away the contacts over a long period of time.