Hi. I purchased a Yamaha brass snare drum recently. It has some rusted spots (some pretty deep). What would you recommend to get rid of them? I cleaned it with Brasso and I could only get rid of the ones on the surface. Should I polish it? Also, I need to use the drum as it is on a gig. Should I apply a coat of lacquer? or will it be alright if I take it out as it is?

Thanks a lot.