Richard, There are several points to look at in fitting (I prefer this term to easing) keys on the keyframe/keypins. I won't get into procedures for dealing with overly large balance rail holes since Roger has done such a good job already. First, remove the action stack so you can remove the keys. Keys that have a mortise drilled in the wood and no shoe at the balance rail require several points. When the mortise is drilled, the bottom of the hole is often uneven. Several supply houses sell a tool that is sometimes called a "balance rail hole reamer." Actually, the design doesn't do anything to the hole but to the thickness of the wood at the bottom of the key. A better name would be "balance rail hole counterbore" or "key mortise thicknesser" (is that a word?). This tool is inserted through the keybutton and pressed down to the bottom of the key then rotated clockwise to remove extra wood at the bottom of the mortise (top of the balance rail hole.) A finger held over the bottom of the balance rail hole tells you when the tip (which approximately 1/8" long) begins to protrude. This way you can easily get a consistent thickness to all of the keys. (Pianotek has this listed as part #KCS-1B.) Note - I find this step unnecessary on keys that already have a hardwood shoe at the bottom (Baldwin and Steinway for example.) Second, while still holding the key in hand, I insert the balance rail hole easer or burnisher (the tapered pointed tool) through the button, rotate it 90 degrees to engage the sides of the balance rail hole and gently work it to ease the sides, but not the front and back, of the hole. This eases the hole clearance but does not cause the key to be "pully" or "chuck" fore and aft. CAUTION - this tool used improperly does far more harm than good. Third, I flip the last mentioned tool over and ease the balance and front keybushings. (Pianotek tool part #JKE-3 or Schaff #R-33) Fourth, polish the keypins and lube with Teflon powder. Different folks prefer different dry lubes but I've found Teflon powder applied with an artist brush to work very well for me. Reassemble the keys to the keyframe, polish the capstans and lube their tops with Teflon powder, reinstall the action stack and you're all set to regulate, tune, and voice. By holding both tools in my hands and picking up each key only once for work I do all of these steps on an entire action in about 45 minutes (once it's out of the piano.) Several years ago I did a few experiments, and shared the results in a class at the Institute, on changes in upweight and downweight from doing these procedures. It typically evens out the feel and puts actions in a good general operating range. We do these procedures on all of the new grands that come through our store (with the exception of the "thicknessing" on the actions with shoes.) Okay, you knew it was coming, here's the shameless plug for the Annual Convention and Institute: Several of the classes that will be offered in Arlington this summer provide all of these details and much more. Exhibitors will also have the above-mentioned tools on display. Note - I mentioned the above suppliers because their catalogs happen to be lying on my desk while writing this. I hope this helps, Allan Allan L. Gilreath, RPT Assistant Director - PTG National Institute July 5-9, 2000 - Arlington, VA email: agilreath@mindspring.com Visit the Institute 2000 web page at: http://www.equaltemperament.com/PTG/ -----Original Message----- From: owner-pianotech@ptg.org [mailto:owner-pianotech@ptg.org]On Behalf Of Richard Brekne Sent: Wednesday, February 23, 2000 5:12 PM To: PTG Subject: Balance pin holes Hi list. It has come to my attention that I should seek advice on proper sizing techniques for balance pin holes in keys. I find often that these are too tight (symptom... keys ride up the pins with play making key leveling an impossibility). Yet as known if they get too loose you get checking problems.. noises.. and other un-nice results. I need someone to write out a complete description of the entire hole preperation process. Not just sizing the bottom of the key.. but the whole tomato..grin Newton.. you are great with this kinda thing.. so if you got the time.. or anyone else for that matter. I would be most apreciatofortisimo. -- Richard Brekne Associate PTG, N.P.T.F. Bergen, Norway
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