Greetings List! I have a question regarding this absolute nightmare of a piano action (1927 Chickering - 5'8") I've been fortunate enough to have on my bench for the past few weeks. After countless repairs, I get it back together and while rough regulating it I find it impossible to get consistent backchecking. When the action is on the bench, I can get he hammers to check, a bit low... but at this point I'll take what I can get. When I duplicate the string height over the hammers with a jig and then play a mezzo forte/fortissimo blow - I get mostly no checking and a lot of double bouncing. The jack is escaping... so I can only come up with a few reasons why this is happening... 1. The rep spring is too strong... unfortunate because they are really difficult to get to on this beast. I don't think this is the culprit, or at least the only one. My guess is... 2. The fact that the backcheck leather is 80 years old, misshapen and worn smooth as a baby's bottom where the hammers should be making contact. It is almost to the point of being spongy in look and consistency. Not leather like at all. This leads me to a few questions... is friction in regards to backchecking coming more from the wedge like positioning of the hammer and backcheck when they come into proper contact? Or, is it from the tail rubbing up against the rough surface of the leather? (I know the answer is probably a combination of both - but what I really want to know is how important is it to have good condition leather on the backchecks? - thus justifying their replacement.) 3. Also, at some point in this piano's lifetime a well meaning fellow attacked it in an attempt to repair it. I can go on and on about the old botched repairs I've fixed and crooked keytops etc... But I won't. But one thing I will mention is whomever it was put new hammers on the old shanks, could it be possible that they were bored and/or had their tails shaped incorrectly (too short) - thus leading to the checking problems. Now if it is determined that the misshapen and ancient backchecks are indeed the guilty party and we ignore the misshapen hammer tail/improper boring hypothesis... I have never had the pleasure of replacing a set of backchecks, how difficult is it? I removed one as a test and it sure wasn't easy to get out, I can't imagine it being very easy to get the new ones back in. There is little information out there on backcheck replacement... so I turn to you my esteemed colleagues! Please offer up any hints, experiences, help, aid, sources of information, etc. that you may have to offer. Thanks in advance. Richard Cromwell Cromwell's Piano Service Detroit-Windsor Chapter
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