Terry, Ed has been doing this for years. It is an important part of my termination conditions for numerous reasons. Also as the tone of my instruments is finally approaching my "grail" tone consistently, this is part...not all...but part of the attention I now lavish on optimizing termination conditions. It:
1- helps encourage a pivot termination, which in my model, given the stiffness of high tension wire, is a more efficient termination, rather than the semi-clamped, restrained termination a wide radius presents
2- allows the string itself, given the point load on the actual termination, to self machine the shape of the actual termination into the capo or agraffe
3- benefits rendering, reducing long term friction at the termination, depending on the contact radius area, potentially, by an order of magnitude
4- assures on the speaking length, that transverse wire movement does not inadvertently cause portions of wire near the termination to contact the cast iron and make noise
5- the pivot is, as Ed said, easier on the wire. encouraging a pivot rather than flexing the wire as it vibrates
As a side note, look at Fazioli treble terminations...a sharp V shape (point of a triangle) triangle extrusion, both as an insert under the capo bar and as treble counter-bearing...a dream to tune, outstanding treble response
As far as accomplishing it, I just flip the plate, and use a combination of die grinder and mill file to remove whatever radius is there at the termination, bring it to a point. Then, after I have a sharp point, very gingerly create a 0.5mm wide flat at the point of the V. I don't try and save the old string marks, as I am often re-spacing strings a bit.
Getting one's hands in there with a file can be uncomfortable, so I have taken a file, clamped it in a vice, and whacked it off with a hammer to create several small files which are easier to manipulate in that area.
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Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
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Original Message:
Sent: 01-05-2021 23:04
From: Steven Rosenthal
Subject: breaking strings at da capo bar
Edward, octave tremolos in the bass.
Btw, what do you think is being done in the factories that damages the wire?
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Steven Rosenthal
Honolulu HI
808-521-7129
Original Message:
Sent: 01-05-2021 23:01
From: Jim Ialeggio
Subject: breaking strings at da capo bar
Floyd...are you sure about that F6 157mm? That's crazy long and super high tension 216 in/lb...crazy high...you sure about that measurement?
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Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
Original Message:
Sent: 01-05-2021 22:42
From: Edward McMorrow
Subject: breaking strings at da capo bar
Most Yamaha's I have tested have hard metal at the capo bars. It is hard enough that it also is abrasive in nature, and as you tune flat spots are worn in the wire at the V-bar. Some Steinway's also have this issue. And a few Kawai's from the 1980's that I have seen. Too round V-bars make the wire flex rather than pivot, this increases elastic deformation too.
I have also come to believe that many factories damage new piano wire during the stringing/chipping process. This doesn't show up as string failure for many years. Then there are some wound scales that place the BP too high and this makes for easier breakage.
I think if a piano is designed with proper BP, termination points, wire type and stringing/chipping processes; string breakage would be rare and we wouldn't be tempted to tell people they can't play the piano with full force.
That said, I still can't fully explain why the gospel style of playing will break wound strings so readily. I suspect chaos theory is involved.
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Edward McMorrow
Edmonds WA
425-299-3431
Original Message:
Sent: 01-05-2021 19:48
From: Jim Ialeggio
Subject: breaking strings at da capo bar
yeah...Paullelo's "stress weight" is BP%
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Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
Original Message:
Sent: 01-05-2021 18:34
From: Floyd Gadd
Subject: breaking strings at da capo bar
I restrung a 1965ish Yamaha G3 using Paulello XM in the treble. Working from Paulello's "Typogram", I see that using standard wire, F6 (157mm/.9mm) would be at 85% of breaking tension. Using Paulello XM, the wire of the same diameter and same tension (and, I understand, same inharmonicity) is sitting at 69% of breaking tension. Am I using the right language to describe this? The chart lists the column in question as Stress %. In any case, I see this as a significant advantage. A great tool to have in the toolbox.
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Floyd Gadd
Regina SK
306-502-9103
Original Message:
Sent: 01-05-2021 17:52
From: Peter Grey
Subject: breaking strings at da capo bar
It's a little like drivers who accelerate aggressively and then stomp on the brakes at the last minute. They just can't figure out why they have to replace their brakes every 10k miles and their tranny fails at 35k. Must be defective. Operator error. 😩
Pwg
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Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com
Original Message:
Sent: 01-05-2021 15:00
From: Geoff Sykes
Subject: breaking strings at da capo bar
I've had several piano owners who were breaking strings because they were overplaying the instrument. At least two complained that the piano was defective. In one case the customer finally listened to me and the manufacturer, understood, and upgraded to a larger piano. Problem solved. In another, the customer had purchased a small entry level upright but his kids were incredibly talented power players. Their teacher insisted that the loud parts be played as powerfully as possible, and they would break plain wire strings weekly on this new piano. They wouldn't listen to either me or the manufacturer and I finally had to walk away. On a third piano I have to agree with Wim. Customer had a new Yamaha U3 and instantly started breaking bass strings at the top termination point. She, too, was a power player, but admitted that much of her banging was not because she wanted it loud but that it was a way to express aggression. With her approval I increased let-off by a good 1/4". The result, while I never would have accepted it on my piano, was that she didn't have to change how she played, stopped breaking strings and actually loved the change in performance. I still tune for her. She hasn't broken a string since and insists I leave the regulation as is.
An interesting demonstration is to show the customer how a string behaves at the termination point with how a wire bends. With the customer that I could not help I used a wire coat hanger as an example. I held one end of the coat hanger wire with a pliers and sort of plucked the wire as a demonstration of how a normal string should behave. With that minimal amount of movement there should almost never be a problem at the termination point. But, with excessive hard playing that wire moves much further and is actually bending at the termination point. Still holding the coat hanger with the pliers I then bent it back and forth a bit more aggressively and within a minute or so I had successfully broken the coat hanger wire at the pliers termination point. I saw by their faces that they understood what I had demonstrated but then they immediately went back to insisting the the piano was defective. It's a good demonstration of what's actually going on but you still have to have an audience that's willing to accept the results for it to be effective.
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Geoff Sykes, RPT
Los Angeles CA
Original Message:
Sent: 01-04-2021 22:09
From: Petrus Janssen
Subject: breaking strings at da capo bar
Greetings and Happy New Year to All with lots of health, joy and happiness.
One of my customers bought a new Yamaha GB1 in 2005 and the strings in the treble section keep breaking (different gauges), all at the capo d'astro bar which is a weird place to break after 15 yrs of use.
Could this possibly be because the bar was not polished properly?
Thank you,
Peter
Janssen Piano Services
678 416 8055
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Petrus Janssen
Peachtree City GA
678-416-8055
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