Al will weigh in on this on in a bit and give the correct answer. He is an expert on this. But I do want to say that do not use the same wheel for wood that you have used for the bands. It will just move all that black into the pours of the wood, and then you will have a real mess. I have a wheel for tripoli and one for white diamond that I use exclusively for the metal bands.
Also, when I am buffing my calls that have a metal band installed, I put that blue painters tape on the metal band so I don't get the metal fouling up my buffing wheel.