This is a multi-part message in MIME format. ---------------------- multipart/alternative attachment I mentioned the plastic jacks because it was the only difference that I could see. I don't see why they would make any difference either, though = I have not actually taken one out and held it side-by-side a wooden one. =20 Loose hammer flanges sounds like a real likely culprit. How many times = have we checked the pinning on a brand-new hammer flange only to see eight or = ten swings? Since this is dealer prep I think I was actually avoiding that = as a possibility. However, now that it's been suggested as a possible = solution I can take that back to the dealer and find out how much they want to = invest. =20 Springs will be the test after that. All I need to do is slip it out = from under the loop and stretch it out a bit, right? =20 -- Geoff =20 -----Original Message----- From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org] On = Behalf Of Susan Kline Sent: Monday, July 11, 2005 11:29 PM To: Pianotech Subject: Re: Mysterious unsolvable Yamaha double-striking uprights Interesting about the plastic jacks, though I don't see what difference = it would make.=20 For some kind of relief, you might try repinning the hammer flanges = firmer. Also make sure there isn't a rail set up to stop the motion of the jacks = too soon.=20 If it's still driving you crazy, you might widen the letoff a hair, and maybe strengthen the hammer springs a little bit.=20 Good luck - I've seen this on Yamaha big uprights and also on Kawai big uprights, though not all of them, or this bad. For some reason, I = haven't found it on consoles or short uprights. Maybe I just didn't look ...=20 Susan At 11:04 PM 7/11/2005 -0700, you wrote: Greetings -- =20 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.) =20 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.=20 =20 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.=20 =20 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.=20 =20 That's all the clues I have. Anybody have any idea what's going on, and = what can be done to correct it? =20 Geoff Sykes Assoc. Los Angeles Chapter ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/89/7a/77/5e/attachment.htm ---------------------- multipart/alternative attachment--
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