Original Message:
Sent: 11/15/2024 6:40:00 PM
From: Peter Grey
Subject: RE: Restringing Baldwin acu-just with interesting issue
I have dismantled several grands that turned out to have seriously contorted plates straight out of the factory. Flexed so badly that, had I done it, I would have anticipated breaking the plate. But no damage. There's more wiggle room there than we were led to believe. I will of course correct what I can, but I can't always eliminate all of it.
Peter Grey Piano Doctor
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Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com
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Original Message:
Sent: 11-14-2024 21:20
From: William Truitt
Subject: Restringing Baldwin acu-just with interesting issue
Not in my experience. If you are lowering or raising the plate, the nose bolts need to be reset also. There may still be some flexing of the plate near the pinblock area, but I believe that would be small
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William Truitt RPT
Bridgewater NH
(603) 744-2277
Original Message:
Sent: 11-14-2024 12:06
From: John Pope
Subject: Restringing Baldwin acu-just with interesting issue
Veering off subject, but I have to ask the following:
If you raise or lower the plate with WNG bolts after stringing, with the plate firmly screwed to the pinblock, you are flexing the plate. Is this a problem?
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John Pope
University of Kentucky School of Music
Lexington, KY
Original Message:
Sent: 11-04-2024 04:48
From: William Truitt
Subject: Restringing Baldwin acu-just with interesting issue
Roger, I believe that you are a rebuilder, yes? If so, you can have it both ways by using WNG plate bolts or making your own.version thereof. You can set plate height globally with the adjustable plate bolts, and dial it in for each string with the vertical hitch pin modification. It can be adjusted after stringing also.
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William Truitt RPT
Bridgewater NH
(603) 744-2277
Original Message:
Sent: 10-31-2024 11:47
From: Roger Gable
Subject: Restringing Baldwin acu-just with interesting issue
Chris,
I've always reasoned that Baldwins acu-just system was an excellent method to adjust downbearing, especially on aging boards. Unfortunately, it only addresses the duplex side of the bridge. There are caveats when you only address the duplex side. There could be excessive downbearing on the speaking side, creating too much net downbearing or there could be excessive negative downbearing. If so, the net downbearing could possibly pull the bridge/soundboard up - although that would be a rarity. I have found these imbalanced conditions are not an exception as you state. They are a condition that exists almost 100% in both new and old pianos.
It's unfortunate my false beat treatise took so long to complete and submit for Journal publication, as this issue is addressed in great detail. Scott Cole informs me it won't be published until possibly January and I'm unwilling to address this subject in a condensed form for this forum.
P.S. Chris, may I suggest you place a disclaimer on the YouTube video stating your acu-just demonstration is not for educational purposes.
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Roger Gable RPT
Gable Piano
Everett WA
(425) 252-5000
Original Message:
Sent: 10-30-2024 19:27
From: Chris Chernobieff
Subject: Restringing Baldwin acu-just with interesting issue
Hi Roger,
Lets just say for a moment you are correct on point, but I believe that would be more the exception and not the rule. On old boards you have to make compromises and use common sense to make things work with "damaged" goods. I for the most part work on new soundboards with a 50' radius and set the the bride height and bearings within my preferred tolerances. My videos are not educational videos per se, but are more "in the moment" videos that can be learned from. So, every possible scenario is not implied.
All the best.
-chris
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Chernobieff Piano Restorations
Inventor of Inertia Touch Wave (ITW)
Advanced Resonant Compression Engineered Soundboards (ARCHES)
865-986-7720 (text only please)
Original Message:
Sent: 10-29-2024 15:03
From: Roger Gable
Subject: Restringing Baldwin acu-just with interesting issue
Tremaine,
The original bubble gauge was made by Tom Lowell sold through Pianotec. Over the years I purchased two from them. When Schaff took over Pianotec I purchased another one for my false beat research. I was disappointed. The construction was compromised. The glass bubble tube fell out, the bearing pin bound up prohibiting any meaningful reading and the calibration angle was so far off that the adjustment screw always needed to be set at the extreme end for most pianos.
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Roger Gable RPT
Gable Piano
Everett WA
(425) 252-5000
Original Message:
Sent: 10-29-2024 14:40
From: Tremaine Parsons
Subject: Restringing Baldwin acu-just with interesting issue
I meant to also include that I have most often seen rebuilders use the bubble gauge method to set accu-just hitch pins. I can't recall off hand who initially sold the downbearing bubble gauge and if they are still available. Can anyone update on availability?
I personally believe that this would be the best method.
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Tremaine Parsons RPT
Georgetown CA
(530) 333-9299
Original Message:
Sent: 10-29-2024 14:32
From: Tremaine Parsons
Subject: Restringing Baldwin acu-just with interesting issue
Roger,
You have raised an excellent point. David explained this method around 1990 and he may have refined it. I should have mentioned that I believe the method was intended to be a guide and did not intend to give absolute correct numbers. Unfortunately we can no longer consult with David on this. I should update the web page to include this point. I've always been mostly a messenger so you have given me a "heads up" with good food for thought.
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Tremaine Parsons RPT
Georgetown CA
(530) 333-9299
Original Message:
Sent: 10-29-2024 14:00
From: Roger Gable
Subject: Restringing Baldwin acu-just with interesting issue
Tremaine,
Reading from David Betts diagram (http://goptools.com/dbearing.htm I'm unsure if his calculation is correct regarding proper downbearing. Help me here. It appears he is simply calculating from some arbitrary point on the top of the bridge to that of the aliquot to acquire an appropriate downbearing angle. If my understanding is correct, then his angle calculations are incorrect. Proper downbearing angle is not derived from some arbitrary point at the top of the bridge but calculated from the surface plane line of the bridge to that of the aliquot.
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Roger Gable RPT
Gable Piano
Everett WA
(425) 252-5000
Original Message:
Sent: 10-29-2024 12:17
From: Tremaine Parsons
Subject: Restringing Baldwin acu-just with interesting issue
Tim,
You can also use the below method taught to my by the late David Betts of NBSS. You can use this as a reference depending of the crown on the soundboard. You can use drill bits for gauges.
http://goptools.com/dbearing.htm
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Tremaine Parsons RPT
Georgetown CA
(530) 333-9299
Original Message:
Sent: 10-29-2024 03:25
From: Delwin Fandrich
Subject: Restringing Baldwin acu-just with interesting issue
Marketing hype aside, this system was developed to aid manufacturing. It allowed the company to fully process the bridges 'on the bench' before they were glued to the soundboard and installed in the piano. It also allowed the workers to "properly" set string bearing regardless the ambient relative humidity (hence variabilities in soundboard crown). The floating string frame mounting was intended to get the string frame relatively close to 'ideal' and then the strings could be adjusted up or down on the pins to fine adjust for string bearing no matter what.
Others have given suggestions for setting the string height on the pins. I'll just add (in response to your question #2) that it was my preference that the strings should never, ever, be more than 10 mm above the surface of the string frame. Five mm (or even less) is better. Yes, I've seen them higher. But, remember, the higher the string on the hitch, the greater the stress on the string frame. If you can't get down to this, raise the height of the string frame. It's not all that hard to do but I can't imagine why it should be necessary in an older piano.
Think in terms of an ordinary string frame. There is a bearing bar back there someplace. How would you go about setting string bearing on that? This is not all that different except that you have some adjustability.
Don't bother trying to set each string pair to some individual height. Establish a reasonable string angle at the first and last string of each section (and, perhaps, one in the middle of the section) and level them all to that height. It's not all that different from a "normal" configuration. You don't see those wandering all over the place, neither should these.
ddf
-- Delwin D Fandrich
Fandrich Piano Company
Piano Design and Manufacturing Consulting Services -- Worldwide
6939 Foothill Ct SW -- Olympia, WA 98512 -- USA
Phone 360.515.0119 -- Mobile 360.388.6525
Original Message:
Sent: 10/28/2024 9:49:00 PM
From: Tim Foster
Subject: Restringing Baldwin acu-just with interesting issue
Hello,
I'm restringing my first Baldwin (model L) with acu-just hitch pins. I spent some time with factory documents and I think I have my head wrapped around the system. To set downbearing, I have a digital level/angle gauge placed on top of a downbearing rocker gauge, zeroed out when tilted on the speaking length. I then rock towards the hitch pin for exact angle. I'm puzzled: when restringing, I placed the strings towards the top of the hitch pin and was still getting positive bearing. Moving the string up any more is not possible, and the portion that needs to be set with 0.5 degrees (notes 23-40 off the top of my head) is reading around 1 degree. I took photos prior to removing the strings, and the strings were significantly farther down the hitch pin in the original configuration.
I believe the piano did spend years in a much drier climate before being moved to South Central PA. It has had a Dampp Chaser for many years at this point as well.
Questions:
- Is it possible downbearing was set for a drier climate?
- How close to the top of the hitch pins can I safely set the string?
- Additional advice in this situation?
- Am I missing something
Thank you!
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Tim Foster RPT
New Oxford PA
(470) 231-6074
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