Notice the bend of the hitch pin. When the string "releases", the hitch pin sends the string up at about 45 degrees and with that angle, it usually has enough upward momentum to clear the rim of the piano.
Ken Gerler
----- Original Message -----
From: Kerry
To: pianotech at ptg.org
Sent: Saturday, April 18, 2009 8:29 AM
Subject: Re: [pianotech] Tuning dangers (was Brands prone to breaking plates)
I've wondered about that too, and also puzzled over how the string escaped from the case. It sure seems that between the struts and the end of the case, most of the kinetic energy would have been absorbed before it got out, so how could it come out straight enough and with enough force to fly that far that fast? I wonder if the amount of twist on the string, like rifling on a bullet, could be a factor. Also, the fact that there have been no incidents of concert pianist injuries (that I know of) would seem to speak to the rarity of the phenomenon.
Kerry Kean
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From: Avery Todd [mailto:ptuner1 at gmail.com]
Sent: Saturday, April 18, 2009 5:22 AM
To: pianotech at ptg.org
Subject: Re: [pianotech] Tuning dangers (was Brands prone to breaking plates)
Claude,
I've also had one break that way at a church where I was pianist years ago. Thankfully, any "body" was far enough away, no one got hurt!
The nested pianos is something I'd never thought about that way before. When I was at the university (& other places), I've tuned many times with the pianos in that configuration. One other thing about that is that the piano one (or both) of them usually always has the lid removed. Wonder where the string might go in that case? Especially if they're in front of an orchestra!
Avery Todd, RPT
Houston, TX
On Fri, Apr 17, 2009 at 11:26 PM, Claude Harding <charding88 at comcast.net> wrote:
Kerry,
I've had a couple of bass strings break like that. I usually lower the lid when I tune the bass section, especially if there is anything precious or expensive in harm's way.
I also wonder about the danger duo pianists might be in while playing "nested" grands in concert. The pianists in this set-up are often in the direct "line of fire" if a bass string were to break.
Claude Harding
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From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of Kerry
Sent: Friday, April 17, 2009 8:43 PM
To: pianotech at ptg.org
Subject: [pianotech] Tuning dangers (was Brands prone to breaking plates)
That reminds me of an incident when I was tuning a Baldwin SD-10 for a visiting artist at a local college. I had the lid up, and one of the low single bass strings broke at the pin and shot out the back of the piano and flew over 40 feet like it was fired from a gun. Fortunately all it hit was a heavy curtain. I've never had one fly out of the piano again, but needless to say I'm very careful about having anyone behind the piano when I'm tuning!
Kerry Kean
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From: John Ross [mailto:jrpiano at win.eastlink.ca]
Sent: Friday, April 17, 2009 7:11 PM
To: pianotech at ptg.org
Subject: Re: [pianotech] Brands prone to breaking plates
The plate that broke for me, was due to pinblock separation.
I was just new in the business, only instruction, an inferior correspondence course.
In the 70's tuners around here would not help as they were thinking you would be their competition.
I hadn't joined the Guild, or started going to conventions, so my knowledge was minimal.
The piano was away down in pitch. Now I would look for the signs of the separation, as indicated in previous posts.
The strings were vibrating against the plate on hard playing.
I, naively thought, that when I brought it up to pitch, it would push the soundboard and strings away from the plate.
It kept on slipping back in pitch as I was taking it up, and suddenly, BANG. I nearly had a heart attack, my heart beat went away up.
Now I check if the pitch is down a large amount, and inform the customer of the possibilities.
Another tuner told me a plate broke on him, and a piece of the plate went through his pant leg. If it had been a little closer, it would have shattered his leg.
John Ross
Windsor, Nova Scotia
----- Original Message -----
From: Andrew Remillard
To: pianotech at ptg.org
Sent: Friday, April 17, 2009 5:42 PM
Subject: Re: [pianotech] Brands prone to breaking plates
Back to the list.
J. Bauer open face 1910's
Bechstein same period
Weber 11910's open face
I am starting to see a pattern here. I have found four different type of harp breaks. The open face harps tend to have too little iron through the pin field and fail often across what little strut material they have.
Struts often break because of poor factory setting, improper "rebuilding", and tooners who have strange notions about using nose bolts to adjust voicing. (I am not making this up!)
Pin field failure. Since the stress here shouldn't be that severe I would imagine most are caused by casting problems or a very poorly fit pin block which led to more pressure on the harp from the tuning pins than should have been present.
And the finale one is the treble hitch pin field breaking off. This tends to be the loudest and most frightening. I had this happen once while tuning a spinet. I had just pulled my head up from looking at something under the key bed when it happened. As others have said, it does get your attention.
--
Andrew Remillard
ANRPiano.com
2211 Curtiss St.
Downers Grove, IL 60515
630-852-5058
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