Allen Leigh rote, 2/7: <<Newer pianos I've tuned don't have the high friction to string movement that I encounter in old pianos, and I don't do as much hard pounding on them as I do on older pianos, although I still hit the keys hard several times.>> Sad but true. When the string friction is higher than the pin friction, the only thing which will set a stable unison is brute force. As long as pin friction is the higher, you at least have the chance of finding out where the segment tensions are, using the "bump-up-bump-down" technique. If you're looking to avoid trashing your hands and wrists, you'll be glad to know that this takes far less energy and gaves you far more mechanical advantage than seeing what gives when you slug the string and it gives a yank outwards along its length. Fellow NH Chapter member Doug Kirkwood and I made a spreadsheet model of note #52 on a Steinway B. Given a maximum 0.47" upward displacement of the string observed at the strike point upon a blow by the hammer, the tension increase in the segment from the point of impact back to the capo was a measley 11oz! About lubing high friction bearing points, Stephen Brady rote: <<.....I've found that applying a lubricant such as CPL with a brush at the juncture between bridge pin and string, followed by pressing the strings on the bridge with a "false-beat suppressor" type tool, will suddenly make the piano tunable. Some pianos in this category that come to mind are Steinway verticals and certain Wurlitzer studio uprights from about 30 years ago.>> Yup, the two most notorious high string friction models in my experience, and I'm not shy to back off the pressure bars on them. But I keep getting my heart broken everytime I try someone else's magic wand and it doesn't work for me. If the pin torsion breaks before the friction grip at the capo/vbar is overcome, solid unisons are a shot in the dark. If lubing bearing points advances the overcoming of string friction so that it follows the breaking of pin torsion more closely (read less at a distance),it's nothing which is useful to me. String fricton has to be lower than tuning pin friction. It's the coordination between these two whcih determines how easily a piano will let me tune it. Bill Ballard RPT NH Chapter, PTG "There are fifty ways to screw up on this job. If you can think of twenty of them, you're a genius......and you aint no genius" Mickey Rourke to William Hurt, in "Body Heat", discussing arson.
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