> am I asking for trouble with the action geometry? Yes, unless done properly. You need to run a line from wippen center pin to key balance point and determine where the capstan and wippen cushion should intersect this line. Get a sample of the Renner wippen that has the cushion closest to this line. Then build a block of wood with a capstan in it that you can adjust up and down and move front to back to determine it's optimum location to get the location that provides the proper "strike ratio". A piano action is a series of levers. David Stanwood has empirically determined that a strike ratio of 5.5:1 is near optimum. Strike ratio is determined by weighing the hammer weight from center pin to strike point, weighing a wippen from pivot point to capstan contact point, weighing the key from balance rail to key front, weighing the key from capstan to key front through the balance pin hole, the up weight and down weight of the key and subjecting this information to a formula that gives you the exact ratio. You have a unique opportunity to do this job right and well the first time. It will take a little forethought, planning and experimenting but it can be done. Be careful to get a set of hammers that very closely conform to the old ones in weight. If these are not original you can determine what the weight should be by placing hammers from you junk drawer on shanks until you get an average of up and down weight in the 36 to 38 gram range. You can do sort of the same thing with your up and down weights by installing a few hammers and your new shanks, install the new wippens and go though the up and down weight measurements and try to find an average location for capstan location by getting the average of the up and down weights to 38 to 40 grams. If your capstan location is far off the center of the wippen cushion you have hammer that are too heavy or too light. THere are a number of folks on the list than help step you though this process. Newton
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