Most all effective spinning weapons work off of momentum. Speed and weight combine to form momentum, the more momentum you can build up in a heavy object, the larger the impact you make when you hit with that object. however you have two huge issues to deal with in high mass/speed spinners. The first is a common law of physics, all actions incur equal and opposite reactions,.. when you hit another robot hard with a traditional spinner your bot absorbs nearly as much impact energy as the other bot receives. So basically both bots take a nearly equal hit, (depending on what you hit and at what angle some variations exist of this rule) but regardless its basically true. Hopefully your bots spin weapon is designed to properly absorb that hit, and wherever you hit on the other bot, is not. The other problem traditional high mass spinners have is that they need a few seconds to build up speed after a solid hit brings there spinning mass to a near or total stop after only one or two hits. and additionally if not managed properly a motors stall current, witch is often many times its no load current, can easily fry electronic speed controls or the motor itself. this is a weakness that can some times be worked with particularly with fast low wedges, and is probably one of the reasons entanglement devices are prohibited (unfortunately).

Hammer Mills seem to be a hybrid of momentum based spinning weapons, with a Hammer Mill you have a little less impact mass than a traditional spinner all of the speed, but the impact does not travel back to the drive train. and the best part is, your spinning weapon does not lose all of its momentum from one or two single hits. If designed right, you rarely if ever stall out, because of this, you commonly get multiple hits especially if you have the torque to keep the weapon spinning..

Hammer mills basically work off of centrifugal force. A spinning mass pulls outwards away from the center point of its axis. (when you spin a pizza in the air, when it comes back down from its spin its a larger diameter pizza, due to syntrifical force and the fact that the dough is easily stretched) the faster the spin the more outward force. in a hammer mill you typically have a spinning disk that holds a balanced number of swinging "hammers" along its outer edge. these hammers are allowed to swing freely (preferably only on the same plane as the spin, and not able to touch each other) only the hammers make contact as a weapon, and when they hit they transfer some of there momentum energy into the strike surface, but because they are not tightly fastened to the primary disk or drive train, they take most of the return impact themselves and simply fall backwards After they pass there strike point. Then centrifugal force pulls them outwards again, often times ready to hit the surface again by the time they make a full revolution. Plus, while consecutive hits will slow down the hammer mill, you will rarely ever stall out and can usually get back up to full speed quickly after a series of strikes. With this method you don't make one extremely hard hit, instead you make many medium hits. and need to absorb very little of that impact yourself. The only downfall is that hammer mills have more moving parts and are more complicated to get just right than a simple spinning disk with a "tooth" in it. so often lots of testing is needed to perfect what your trying to accomplish.