It would be helpful to know the current bore specs, but I would consider replacing the shanks with either 16 or 16.5mm whichever gives you the proper ratio for the given SW you intend to use and gets the action to regulate properly at 10 mm dip and 43 - 45 mm blow. Then I would check the magic line to see where the capstan falls with the action regulated with the new parts. If raising the stack puts the magic line more on target, I would raise the stack which will take up some of the gap at the rest cushion. The remainder of the gap I would fill by adding felt or installing a thicker rest cushion. David Love davidlovepianos at comcast.net www.davidlovepianos.com Case in point. (here is the puzzle part) I am currently preparing to rehammer and reshank a 10 year old D which has a very high string height and a very low ratio (4.9). At 1 7/8 blow, the shanks are almost 1/2" off the cushions. This action currently has 17 mm knuckle distance, SW in the upper middle range, FW in the average range, and ridiculously low DW of 50 gr. in the bass, 44 gr in the area of note 25, and 40-42 gr. from note 32 on up. BW on A0 is 40, tapering down to 33 at note 73. I could elect to reduce the FW, keeping all other things near the same. However, this would not address how high the hammers are off the rest cushions. It would not increase the power,either. What would you do? ( I already have a plan of action, which entails three changes, but will be interested in other's interpretation.) Regards, Ed Foote RPT http://www.uk-piano.org/edfoote/index.html www.uk-piano.org/edfoote/well_tempered_piano.html
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