I also take issue with Mr. Stern's article. Mr. Stern states that if an applied force is not aligned in the direction of travel, then there are energy losses. He also claims that these energy losses are due solely to the "vector" effect and are separate from losses due to friction. The fact is there are no inherent energy losses when a force is applied off-axis. And unless there is friction involved, the force will be the same for both directions of travel. In the particular example of the capstan-heel cushion interface cited by Mr. Stern, there may indeed be energy losses. But these losses are due to the friction as the capstan slides slightly on the heel cushion. This observation should in no way detract from the practical value of Mr. Stern’s article, which is that the geometry of the capstan-wippen interface can affect touchweight. -Robert Scott Detroit-Windsor Chapter, PTG
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