I´m not much into polishing, but I do have some stuff for it. Sisal, felt and cotton flap wheels, and four sorts of sticks to do the trick. I think the recommendation is, Red is for "coloured" soft metals, brass, bronze, copper, silver and gold (the last two haven´t appeared in the shop lately in significant numbers, I´m afraid). The Green stick is for "hard" metals, chrome plated, stainless, hardened steel, nickel, platinum, etc. The blue and white sticks are for anything else. I usually try what works best, and use that, disregarding what they´re actually intended for... The white stick is often best with aluminium, but not always, there are different grades of ali, also cast and drawn pieces behave differently, etc. Blue is often best for cast iron.
I seem to work with red rouge by far most often, the green stick I´ve used for a few cm´s while I´ve bought 3 sticks of rouge. Or it might be because the red stick is softer? I do a lot of my stuff in brass, so that might also explain it. And rouge seems to polish just about anything pretty good. Even wood.
There are special polishing compounds available for horn material, but I´d first try the metal polishes. They work usually just fine, with non-metals also.
So, what you might do is to try what works best. The green stick I´d probably skip, horn is far too soft for it. When buffing, use very little of the compound only and don´t overheat the workpiece (don´t press too hard!). Polishing horn should not be smelly - if it is, you´re slightly burning it.
And of course, before you even try polishing, the surface must be smooth and without scratches - the usual wet´n dry emery paper routine, 100, 280, 400, 800, 1200, as you know. That´s the smelly work...
And, when you try what works best, wash the workpiece between each trial, so there´s nothing left of the previous compound!
I wouldn´t worry about speed control, as long as the wheels are of "normal" sizes (15-20 cm dia.). If the wheels are a lot bigger, and they turn really fast, they will start to disintegrate, throwing lint everywhere, and easily catching the workpiece, throwing it into the worst accessible corner of your shop... Then it would be a good idea to slow the machine down.
Hope this helps, although it is mostly about polishing metals. Good luck with the antlers!
