Re: Steel wool for metal polishing...when to use and when not to use?
Well, I guess I can write more words:
The steel wool will leave little fibers in the scratch pattern's jagged edges. These little fibers will rust, meaning the exhaust tips will show rust marks. It's not the exhaust tips themselves, but the fibers leftover from steel wool.
Even though the steel wool used was 0000, it's coarse by comparison to the smooth finish that the exhaust tips had. That's why the tips now have a brushed/raw look to them. They can be polished back up to a higher shine, but since stainless is hard, the process will require more effort than aluminum would.
If you do want to return a high shine to them, stainless is one area where speed will be your friend if you use a mechanical aid - polish and a higher speed on a drill with an attachment will help reduce the effort and time involved.