I wrote: "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). " >>Dale asks: Before I comment further what's the dip at the pin or wherever you measure it. This is very interesting and peculiar.<< The dip is not consistant,( I ain't gonna regulate it before I do all the other work), but averages around .400" with .30" aftertouch. David writes: << 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. >> Raising the stack leaves the backchecks behind, so I try not to do that any more than necessary. Current bore specs? These are stock Steinway factory original hammers, I didn't measure them, but did check to see what was necessary for a 90 degree meeting of hammer to string. I will need to bore the bass at 58 mm, middle sectionat 49, and then 48 mm for notes 54 on up. There is just enough room on new Steinway hammers to do this and still have 26 mm of tail lenght. The 16 mm shanks do not leave enough room for the jack between the knuckle and backstop felt. I didn't check action spread, but I suspect it is either correct or slightly wide. The rest cushions have already had an additional spacer put in them through the middle section to prevent repetition failure. Alan writes: >>How's the convergence between key and wippen<< didn't measure it >>What's the key ratio? << didn't measure it,(there will be no time or budget to change it, and I don't see that I will need to ) >>Are the bore specs (string height minus hammer center height) in the normal range?<< Yes >>What is the knuckle diameter?<< 10 mm >>On a well-regulated note, how does the jack relate to the knuckle at full dip? << It is acceptable, >>What is the dip?<< see above >>What are the friction numbers?<< I don't use them for my action analysis, anymore (unless something is just too weird). 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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