<html> <body> Al - Don't despair.  Your thoroughness and dedication will pay off.  You will find the answer, and the light bulb going on over your head had better be an LED.  Here are a few more questions: Are you SURE that the key frame is COMPLETELY bedded at the back rail as well as balance rail? What do you mean, in your description below, by "floating"? Can you get hold of a digital camera and post pictures of the parts?  David Skolnik At 09:09 AM 3/19/2008, you wrote: <blockquote type=cite class=cite cite="">Truth be said, I have no answer. I made it work, but didn't really solve the problem.   Keep in mind that everything worked perfectly on the bench but not in the piano. Furthermore I set up my bench with upside down front rail glides (as Baldwin does in their grands) to be able to copy the keybed in the piano. No matter how I set it up, (front action rail floating, center action rail floating, rear action rail floating, or right on the money, that hammers checked perfectly in all the situations, but not in the piano.   How did I make it work? <ol> <li>I repined the balancier to almost no friction. <li>I set the spring to where the hammer would barely rise. (of course I had to re-regulate the flys again) <li>I repined the hammer shank flanges to 7 or 8 swings. (learned that from Fred Drasche at Steinway) <li>I took some of the radius off the hammer tails. </ol>With all that I could not get hammers 1 and 2 (A0 & A#0) to check and on the softest blow some other would not check, but all in all quite satisfactory.   I feel I use a band-aid to correct the problem. Never being able to know the real problem. The customer will be happy, but I have what I believe to be an unsolved problem   I want to thank everyone for their help and input.   Al Guecia Allied PianoCraft PO Box 1549 High Point, NC 27261 (336) 454-2000 <a href="mailto:PianoTech@alliedpianocraft.com"> PianoTech@alliedpianocraftcom</a> <a href="http://www.alliedpianocraft.com/" eudora="autourl"> www.alliedpianocraft.com</a>       ----- Original Message ----- From: "David Skolnik" <<a href="mailto:davidskolnik@optonline.net"> davidskolnik@optonline.net</a>> To: "Pianotech List" <<a href="mailto:pianotech@ptg.org">pianotech@ptg.org</a>> Sent: Tuesday, March 18, 2008 10:47 AM Subject: Re: Steinway M Backcheck Problem > At 08:06 AM 3/15/2008,  Al Guecia wrote: >>OK.......... back to the piano on Monday and check all of this out. > > > OK Al - It's Tuesday.  What's the answer? > > David Skolnik > > No virus found in this incoming message. Checked by AVG. Version: 7.5.519 / Virus Database: 269.21.7/1334 - Release Date: 3/18/2008 8:52 PM</blockquote></body> </html>