>Then put a 45 gram weight on the front of the key and begin to screw down >the whippen magnet so that it gets closer and closer to the key. At some >point the key will just start to move on its own. And as it does, the distance between the magnets increases and the touch weight does too as the magnet repulsion lessens. The down pressure from the repulsion on the back of the key lessens too, but to a lesser degree because of the leverage differences. First class lever in the key, second class lever from the magnet lift of the wippen. From a play standpoint, that shouldn't be a problem since the increase progression should be shallow and smooth, and everything is already moving. There is one more thing though. You have a second class lever doing the lifting, but you also have extra inertial mass on both the second class lever (key) and the third class lever (wippen). Where the magnet lift is a second class lever, providing a mechanical advantage, the inertial mass presents a third class lever and an increased penalty. The weights involved here may not prove to be a significant problem, but it at least needs looked at. Oh, and non-magnetic capstan tools. If it works out, you can also claim the advantage of automatic paper clip control.
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