Wim said: "Lim Sometimes, unless you've got a lot of time on your hands, and are prepared not to charge the customer for the amount of time it will take you to tune and regulate the piano, perhaps the best advice I can give you for working on a square grand is, DON"T." Willem, Although your advice is sound, most of your statements are just not so! 1."Tuning a square grand is challenging, to say the least." If that were true, then how is it that I've done 3 in one day? It just takes special tools and techniques.<G> 2."The strings do not line up with the tuning pins, like on a grand or upright." No they don't, but the tuning pin area has the notes "penned " in. A thorough cleaning before tuning will usually make them ledigle. (Yes the lid has to come off!) 3."The first thing I would do is remove the rail that goes across the dampers. That makes it a little easier to follow the strings to the pins." Nope. The first thing to remove is the music desk. (right side bracket and then the vertical...carefully.) Second thing is to remove the lid. the third thing is the damper upstop rail. (be very careful not to drop the nuts into the action cavity...it's easy to do DAMHIK!) 4."If you have never worked on a square grand, I would advice you not to try to regulate one without a very good understanding of regulating a grand action. " Wrong again! The principles are the same to a certain point. However, the square grand is a "Single Escapement Action" and is quit easy to regulate! The hardest part is getting the hammers aligned to the strings, (special tools needed!). Once that is accomplished, do the let off, (1/8" throughout, if the hammers are in good condition and haven't had over 1/16" filed off, (Not usually the case). If more than 1/16" has been 'ground' off, then compensate for that by allowing more let off distance. All of that is predecated on a 3/8/" dip and the keys need to be leveled, of course. Key leveling can only be accomplished with the 'stack' removed! Do Not try to do that with the stack on! You'll screw up things fer sure!<G> Set the back check to 5/8" and you can get it real close, simply by doing the test where you have one hand on the hammner and the other on the key. Rock back and forth. If the tail drags, at all, on backcheck, it's set too high! One final criteria: You must have a minute amount of lost motion between the jack and the hammer butt leather! Of course, all of the jack springs need to have good spring cord, properly installed. The amount of spring tension is the most critical of all! Too much and the jack will hang up on the butt...too little and the jack cannot force it's way under the butt leather. With a key out, lift the jack to where the spring cord "just" becomes tight with the spring. The jack should be at 45 degree angle when that happens, give or take 5 degrees! Well, that's the short version, but it's really not difficult. Tedious? Yes. Difficult? No.<G> Regards, Joe Joe Garrett, R.P.T. (Oregon) Captain, Tool Police Squares R I -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech.php/attachments/20100826/abb0eec3/attachment.htm>
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