Re: What is the the best polsiher for oxidation, small scratches
I would recommend trying a good polishing compound, such as 3M, Meguiar's, Mother's, and there are many others...By hand first in a small area to see if that is all that will be needed to bring back the shine...
Depending on the surface finish, gel coat or paint, you may have to use a rubbing compound first, or even have to sand/wet sand...
Once you have a working plan, I recommend a variable speed polisher and you should practice on either a not too visible section of the boat, or a separate test piece...start out with a slow speed and very light touch, carry the weight of the polisher...
To actually learn to use a polisher and all of the other steps involved in getting a superior shine, requires practice, patience and some more practice...
Sometimes it is best to try and do it all by hand, to prevent the very likely possibility of burning through the surface...
Once you get everything looking nice and shiny, keep it protected by applying a good quality marine wax at least twice a year...
You might also, get some better advice if you post up some good pictures of the scratches, etc...so the real pros can give you some tips...
Good Luck!