Hammer tails are too short. Tail shape is improper. Backchecks at the wrong angle to tail. It is not easy to lengthen hammer tails, although I am thinking of ways and means, but have nothing to suggest at this time. The shape of the tail is critical to good checksing. More so than would be thought. 2.5 to 3 inch radius works best. I have a little pin in a piece of wood that allows me to rotate a shank around while the hammer tail is being shaped by the disc sander. Roughness is critical and too rough can prematurely wear the backcheck leather. Push the key all the way down and tap the top of the hammer into check. If the hammer goes though check real easily that angle of the backcheck needs to be changed by bending the top of the bachcheck (bck) away from the hammer. If the hammer will not go into the bck the top of the bck head needs to be bent toward the hammer. If the hammer goes deeper into checking with maderate to heavy tapping the angle is good. If the heels have a great amount of wood missing from the tip end you may consider bluing on a piece of wood to replace what was removed before reshaping the tail. If you need more information there was an article on the subject several years ago by Chris Robinson. Newton nhunt@rci.rutgers.edu
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