I have an old motorcycle and the metal on the engine is discolored. I thought it was dirt at first but it does not clean off but if I scratch it it shines. My question is should I sand it first or can I use a compond and a buff? I am only looking for a brushed finish not a mirror like shine. I would also like to know what the difference is between compond and greaseless? And finally I was looking to make some exhaust pipes for the bike from stainless and I want to get a mirror shine and would like to know what to use.
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