On the vertical, move the let-off rail in just far enough so that on escapement, the jack will wedge lightly between the rail and the butt buckskin on some keystrokes. This makes it appear to the casual observer that there is simply a sticky key. The great thing about this is that if you haven't come across this before, you can sit there and stare right at the problem and not see what is going on. Guaranteed to be a laf riot! Dave Bunch
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