<html> <body> You got it TOYOTA!   <G>   Do it this way even when you don't think there is a problem, and note the results.  You are going to be surprised.   On some Concert grands for favorite pianist,  I will have the cheek blocks in and tight, and just tension the rail a little,  then restore after touch by lowering the hammer line. Neat trick for a big concerto, for a not so big piano.  Shush!  did I say that. Have a good week end. Roger At 12:49 PM 5/23/2003 +0200, you wrote: <blockquote type=cite class=cite cite>Thanks muchly Roger... seems to be the description that makes the most sense so far. Very roughly then, adjust the glide bolts so that they all are in contact with the bed, AND all lift the balance rail to the point that the Front Rail is just a nats butt away from being lifted as well... Key height and the rest is set afterwards. Correcto ?   Roger Jolly wrote: <blockquote type=cite class=cite cite>Hi Avery & Ric,                           I have a good minds eye view, of what is going on, but I'm not so sure I can explain it well.   But here goes.  (Send me a deluxe flame suit Conrad). If you have the bolts just touching, there is no compression force acting on the balance rail.  With rapid forceful playing, there is a small amount of bounce taking place at the balance rail, robbing the action of a lot of energy.  It gets dissipated within the frame. Jack the bolts a little further down,  you start to bow the cross struts.  and putting some compression into the rail. , and firmly seating it to the bed.   At the Yamaha Technical Academy, they spend a good deal of time teaching you how to tune these rails in aurally.  takes more than a little practice to get optimum results. The front rail is done first, by tapping on the front rail with a kind of 45 degree blow, to the leading edge of the rail.  (You can hear better than the traditional method of holding a key down and thumping on the key, the front rail punching absorbs a lot of noise,) Then the bolts are adjusted so the front rail just starts to lift, then back off about 1/4 turn.  Next step is get all the glides bedded so the tone is the same when lifting up on the hammer rail, and thumping down on the balance rail. The closest analogy I can think of,  is like string bearing across the bridge.  Too much bearing and a loss of tone, too little loss of tone. Now I will crawl under my rock and smile. Regards Roger    </blockquote>Cheers RicB -- Richard Brekne RPT, N.P.T.F. UiB, Bergen, Norway <a href="mailto:rbrekne@broadpark.no">mailto:rbrekne@broadpark.no</a> <a href="http://home.broadpark.no/~rbrekne/ricmain.html" eudora="autourl">http://home.broadpark.no/~rbrekne/ricmain.html</a> <a href="http://www.hf.uib.no/grieg/personer/cv_RB.html">http://www.hf.uib.no/grieg/personer/cv_RB.html</a>   </blockquote></body> </html>