<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <html xmlns:o="urn:schemas-microsoft-com:office:office" = xmlns:w="urn:schemas-microsoft-com:office:word" = xmlns:st1="urn:schemas-microsoft-com:office:smarttags" = xmlns="http://www.w3.org/TR/REC-html40"> <head> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; = charset=US-ASCII"> <meta name=ProgId content=Word.Document> <meta name=Generator content="Microsoft Word 10"> <meta name=Originator content="Microsoft Word 10"> <link rel=File-List href="cid:filelist.xml@01C586BD.063366A0"> <title>Message</title> <o:SmartTagType = namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="PersonName"/>  <style>  </style>  </head> <body lang=EN-US link=blue vlink=purple = style='tab-interval:.5in'> <div class=Section1> Check also the damper spring = tension.  What may be happening is that if = the damper spring is excessive it will slow down the acceleration of the = whippen as the spoon contacts the lever. But the = hammer will continue on. I can see where this would show up on a slow blow. = <o:p></o:p> <o:p> </o:p> I just reset all the damper springs = on a U3 with very good results. Here is what I posted last week if you missed = it:<o:p></o:p> <o:p> </o:p> FWIW, I played around with the = tensions and ended up with the following settings. Force was measured at the = damper head where dowel was glued. <o:p></o:p> <o:p> </o:p> Bass singles- = 45g<o:p></o:p> Bass wedges- = 25g<o:p></o:p> Tenor- 25g down to 15g at upper = break<o:p></o:p> Upper treble- = 15g<o:p></o:p> <o:p> </o:p> It was interesting that after = training my touch with the gage I could pretty accurately hit my targets just by = feel with the finger.<o:p></o:p> <o:p> </o:p> <o:p> </o:p> <div> Dean<o:p></o:p></fon= t> <st1:PersonName>Dean May</st1:PersonName>       &nbs= p;     cell 812.239.3359<o:p></o:p> PianoRebuilders.co= m   = 812.235.5272<o:p></o:p> Terre Haute = IN  = 47802<o:p></o:p> </div> <o:p> </o:p> -----Original = Message----- From: = pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org] On Behalf Of Geoff Sykes Sent: Tuesday, July 12, = 2005 1:04 AM To: Pianotech@Ptg. = Org Subject: Mysterious = unsolvable Yamaha double-striking uprights <o:p> </o:p> <div> Greetings = --<o:p></o:p> </div> <div>  <o:p></o:p> </div> <div> I did a dealer prep on a = brand new, fresh out-of-the-box, Yamaha MX500 P upright today. Every single note double-struck when played softly. I checked regulation and had to adjust = lost motion on every key. Let-off also needed to be adjusted, but only on = about 10 keys. When I finished these two adjustments the regulation may = not have been perfect but it was certainly close enough. Still, every single = note was double striking when played softly. (Definition of = "softly": Playing the note faster then when you are checking let-off but slower than it = takes to actually check.)<o:p></o:p> </div> <div>  <o:p></o:p> </div> <div> What I am witnessing is this: When I play the note, just before the jack releases from = under the butt the hammer jumps off the jack prematurely and strikes the = string. After striking the string the hammer then bounces back onto the jack, which is = still in it's pre-release position. Continuing through the keystroke results = in the hammer striking the note a second time as the jack finally releases from = under the butt. <o:p></o:p> </div> <div>  <o:p></o:p> </div> <div> This was something new to = the store manager so I called an associate. He suggested I go through the routine = I had just completed, but otherwise could offer no further suggestion. OK, so = I decided to tune the thing while I pondered the matter further. = <o:p></o:p> </div> <div>  <o:p></o:p> </div> <div> Aha! Tuning finished. Let's = see what the other Yamaha uprights are doing. I checked six other, (not used), Yamaha uprights on the floor, (none of which I had prepped, = but all of them allegedly prepped), and every single one of them exhibited the = same double-strike behavior. For comparison I then checked some NON Yamaha = uprights and they all behaved properly. I finally checked the showroom Yamaha = action model, and it, too, was behaving correctly. BUT... It was then that = I noticed that all the Yamahas used in this test had plastic jacks. The = Yamaha action model, as well as the non-Yamaha uprights used in this test, all = had wooden jacks. <o:p></o:p> </div> <div>  <o:p></o:p> </div> <div> That's all the clues I = have. Anybody have any idea what's going on, and what can be done to correct = it?<o:p></o:p> </div> <div>  <o:p></o:p> </div> <div> Geoff = Sykes<o:p></o:p> </div> <div> Assoc. Los Angeles = Chapter<o:p></o:p> </div> </div> </body> </html>