Hi Will, I am no action ratio genius, but here is my contribution anyway. I am going to throw out question which you probably thought of and addressed already, but just in case you didn't: did you bed the keyframe or check the keyframe bedding? As I'm sure you know, this can affect key height and key dip (among other things), sometimes in unpredictable or relatively extreme ways. Probably not it, but worth a minute to check, especially the glide bolts. If everything else is working, would you consider compromising by shortening the blow distance just a bit? After all, folks rarely complain that their Young Changs are not loud enough. That would help you to more easily achieve a key dip with enough aftertouch, and would allow you to position the hammer rest rail in a more comfortable spot. You wouldn't have to bury the capstans as much, either. I usually prefer to slightly adjust a couple of parameters so that "everybody gets along" instead adhering to a setting in one place that pushes other parameters near their extremes. Thanks for describing your brass action spread setter/gauge - I'm going to remember and use that method in the future! Good luck with it, Joe DeFazio Stillertown > -----Original Message----- > From: Will Truitt <surfdog at metrocast.net> > To: pianotech at ptg.org > Sent: Tue, 27 Jan 2009 2:20 pm > Subject: [pianotech] Young Chang Growing Brackets > > To the List: > > I am hoping to get a little bit of advice from my action ratio > genius friends on the forum. I have a Young Chang G-150 which I > have gotten and installed new action brackets to replace the old > growing problem brackets. As best I can tell, this piano was built > in early 1992, which would put it on the cusp between two action > spread values of 112.5 and 113.5 mm. The spec sheet from Young > Chang which I got some years ago says, “Action spread should be set > to 112.5 mm. Models newer than 1992 = 113.5 mm.” I took that to > mean that pianos made after 12/31/92. Which probably means that > this piano should be set at 112.5 mm. But it is a little ambiguous, > and I have been trying to call Derrick Cornejo at Young Chang for > the past few days for clarification, but he is MIA, his mailbox is > full, EVERYBODY’s mailbox is full, and even the operator is missing! > > I set the spread at 112.5 yesterday. This I did by taking a thin > piece of 1/8” brass stock, and carefully drilling two holes in it at > exactly 112.5 on the drill press, and then installing two .050 > center pins through these holes. Removing the shanks and whippens > from their flanges at the ends, I screwed the flanges to the rail. > Then I loosened the whippen rail screws, and moved that rail back > and forth until the two center pins would go into their respective > holes in the flanges. I then tightened the whippen rail screws, > locking in the action spread at that position. So I am pretty > confident that I have been very accurate at setting the spread at > 112.5 mm. > > I also needed to retap the screw holes in the rails, as the old > screws would not go in very far. Once I did that, they turned > nicely. I also had to plug and redrill the holes in the keyfram > that screw the stack to the keyframe, as the two center brackets did > not line up with the old holes. And longer screws for the taller > bracket feet. No worries here. > > I took the action back to the piano today. Installing it, the > hammers were still blocking against the strings. However, when I > set the hammer drop f ar enough away to be sure to get let off, I > was able to back off the let off screws and achieve proper let off > on several test notes. I set the drop then. I had already set the > jack height and position in the window. > > The anomalies here are thus: I was just barely achieving cycling > through let off, with little or no aftertouch, without removing > front rail punchings. The manual asks for 64.5 mm key height (which > the piano was properly set at). I was getting about 9.4 to 9.6 mm > key dip, and could achieve the 10.2mm by removing cardboard > punchings. And it feels ok. I set the hammer blow distance at the > factory spec of 47mm, but had to LOWER the capstans to achieve 4 or > 5 mm to get it down to that value. At which the bottom of the shank > is sitting about 3/16” above the hammer rest rail felt, which is > adjustable and at its lowest setting at that point. The bottom of > the let off rail is sitting about 1/8” above the back edge of the > whippen. So everything is working, but there is not much room. > > I also took touch weight readings on two notes: Note 27 was 55 g. > DW, and 29 g. UW. Note 88 was 53 g. DW, and 36 UW. (These test > notes had been regulated). > > At first I was wondering if the plate was set too low. I didn’t > have my string height guage with me, but I was able to get a string > height at note 77 of about 198 mm. > > But I think the hammer bore is sufficiently accurate to the string > height. Note 1 was bored at 57 mm, note 27 at 51 mm, and note 88 at > 49.5 mm. There is very little wear on the hammers. At let off, the > test notes shanks are parallel to the string plane, not over or > undercentering to any degree. And, with the hammer blow distance > set at 47 mm and the jack position in the window adjusted to line up > the back of the jack to the back of the knuckle core piece, they > form a straight line. At let off, the bottoms of the hammer tails > are even with the tops of the back checks. All of these things are > good signs for action set up. Capstans are centered under their > cushions. > > At least on my test notes, it seems like the piano is going to > regulate ok. It FEELS ok (for a Korean piano) > > The only thing that is holding me back is the fact that I am having > to lower the capstans to achieve the 47 mm blow distance, and remove > punchings to get the 10.2 mm dip (which yields plenty of > aftertouch). That part is odd, but I am assuming that the piano was > set to the correct values for blow and dip at the factory way back > when. > > The essence of it is that if I decide that I need to change the > spread after I have regulated the action, the values I have set will > go out the window and need to be done over again. So I want to be > right the first time. > > So what will it be, boys and giris – is your antenna going up, or > does everything seem hunky dory and I should keep the spread value > of 112.5? > > Thanks for your contribution. > > Will Truitt > > > A Good Credit Score is 700 or Above. See yours in just 2 easy steps! > > > > From: Ryan Sowers <tunerryan at gmail.com> > Date: January 28, 2009 2:19:04 AM EST > To: pianotech at ptg.org > Subject: Re: [pianotech] Grand Mute Rail > Reply-To: pianotech at ptg.org > > > It actually looks like a very clever product. I'm looking forward to > seeing it at the Cal Sate conference. It's about time someone came > up with a practical muting system for grands. > > On Tue, Jan 27, 2009 at 5:17 PM, William Monroe <pianotech at a440piano.net > > wrote: > Al, > > www.grandpianomuffler.com > > WRM > SNIP > > Who sells the grand mute rail/system? > > Al > > > > -- > Ryan Sowers, RPT > Puget Sound Chapter > Olympia, WA > www.pianova.net > > > > From: David Andersen <david at davidandersenpianos.com> > Date: January 28, 2009 2:44:28 AM EST > To: pianotech at ptg.org > Subject: Re: [pianotech] Young Chang Growing Brackets > Reply-To: pianotech at ptg.org > > > > On Jan 27, 2009, at 4:20 PM, Will Truitt wrote: > >> The only thing that is holding me back is the fact that I am having >> to lower the capstans to achieve the 47 mm blow distance, and >> remove punchings to get the 10.2 mm dip (which yields plenty of >> aftertouch). > So what? If everything works, and clears, you're good. 47mm blow and > 10.2 mm key travek is about is about ideal. With a Balance Weight > of 42, it's a little stout for my taste; maybe that can be helped > with lubrication, close checking, and agressive distal jack position > (moved toward the player.) > > >> That part is odd, but I am assuming that the piano was set to the >> correct values for blow and dip at the factory way back when. > Bad assumption, and remember: specs are a guide only. Each action is > custom. > > David A. > > > > _______________________________________________ > pianotech mailing list > pianotech at ptg.org > http://ptg.org/mailman/listinfo/pianotech_ptg.org -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech_ptg.org/attachments/20090128/3dd9c1fa/attachment-0001.html>
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