I like to get .050" (my punchings are calibrated in inches) of key movement after jack leaves knuckle. This can be adjusted by dip or hammer height or both. this allows for a considerable safety factor for generic regulation. Specific applications can result in less for performance, as an example. Place .050" punching on pin and adjust so the hammer falls just at the bottom of the stroke without compressing the felt. Newton nhunt@jagat.com
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