[CAUT] huge pitch raise question

[ed440 at mindspring.com]

A good experiment is to intentionally break strings on a piano that's going to be junked. WEAR EYE PROTECTION.  Tune a string as unison with it's upper neighbor, and the next  upper neighbor, and the next....

The breaking point will vary depending on where you are in the scale.  You will come away with a clear sense of what kind of overpull it takes to break a normal string.

I recently raised pitch on a 1990's Kimball console.  Three midrange strings in a row broke just as they approached pitch. That clearly was a problem with the wire.

Another time  bass strings were popping from a container shipment of Korean vertricals. A careful check showed the strings had been seated with a sharp edged screwdriver, leaving nicks in the wire at the top bridge.

Work hardened strings (heavily played) will break when they are ready, raising or lowering pitch, or with a pianissimo hammer blow.  They break because they are so close to breaking that any disturbance does the job.

There is also some chance that a #4 tuning tip on a #2 pin could work like a becket breaker and snap the becket.

If you're using the right tool on the right tuning pin and not massively overpulling, it really is the string's fault or the piano's fault if a string breaks.
Break a few on purpose and you'll give up lots of guilt.

Ed Sutton

-----Original Message-----
>From: Mitch Staples <staples.13 at osu.edu>
>Sent: Jan 9, 2007 2:07 PM
>To: College and University Technicians <caut at ptg.org>
>Subject: Re: [CAUT] huge pitch raise question
>
>Michelle,
>
>Tuners don't break strings, strings break when they're under stress.  Often
>tuning is when the strings are most stressed -that's my story and I'm
>sticking to it.
>
>I don't break a lot of strings but if the piano has gone a long time without
>tuning I tell the owner to expect a string or two to break.  Then when the
>tuning's done and no strings have broken we all breath a sigh of relief and
>hopefully they don't wait so long to have it tuned next time.  I would say
>that each year about two or three strings break.
>
>In 20 years I've only had one string break on the second pass so I don't
>know what to say about that (maybe I broke 'em all on the first try).  If
>it's happening a lot maybe you're rocking back and forth over the object
>pitch a bit too much.
>
>I usually don't move the pin to the left first, but if I feel some initial
>friction I do.  I think that rocking the pin back and forth increases wear
>on the pin block.  Also I think that my tunings are more stable if I move as
>directly as possible from point A to point B.
>
>I try to bring the whole piano to pitch in one pass without more that 10
>cents or so over pull.  If the piano is new I'll go as much as 30 cents.  If
>the piano is old, no over pull at all.  It's seems to me that older pianos
>don't need so much.  95% of the time one pass will do it.  For improved
>stability the quicker I can get through a pitch raise the better.  You can
>get through many pitch raises without using mutes accept in the temperament
>8ve.  It takes some practice but it saves about 10 minutes of what I
>consider pure torture.  An ETD helps as it will usually ignore the incorrect
>pitch in favor of the target pitch.  As long as the piano is generally at
>pitch the fine tuning is as solid as ever.  I usually warn people that after
>a big pitch raise the fine tuning won't be as stable as it will when the
>piano is maintained properly.
>
>I've noticed the increase tork you mentioned.  I figure it's a combination
>of increased tension and the pin being screwed deeper into the block.
>
>
>Mitch Staples
>
>-----Original Message-----
>From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org]On Behalf Of
>Michelle Stranges
>Sent: Monday, January 08, 2007 2:07 PM
>To: College and University Technicians
>Subject: [CAUT] huge pitch raise question
>
>
>Hi folks-
>
>Happy New Year!
>
>:D
>
>It happens more often than I'd like (and once is enough to be honest)
>and while I "feel"  that it's not my lovely hammer technique ;)  ,
>maybe it's something to do with some sort of "string thing"..
>
>Has anyone else run across this?
>(Or maybe a PTG article I have overlooked?)
>
>Upon visiting a fairly new piano and finding it dreadfully flat (50
>cents or more) , I carefully yet quickly, raise it up at least half
>of what it was.
>And I do have a (good?) habit of initially moving the pin in the flat
>direction before moving it sharp in order to loosen any friction from
>any rust or whatever that may have accumulated. Just a *quick* jerk
>to the left- nothing serious at all.
>
>Now.. having raised the piano up (with a second pass to at least get
>it up to pitch) I start doing a "fine tuning".
>
>it is either at this second pass or my fine tuning where strings
>start to break.
>In the usual places too- nothing out of the ordinary.
>
>(Am I doing "too many tunings" (up to 3  times) to raise this
>completely up? Seems like that wouldn't be an issue,  especially if
>it's new(er)?
>Have I introduced some sort of unusual friction/heat or something??
>
>
>Now this doesn't happen all of the time, but I am acutely aware that
>it could and I wonder if there's something in my technique or my
>sequence of pitch raising that makes these newer strings break. (I
>could understand some strings breaking if the piano was older..)
>
>I know tuners who on the first go, bring the whole piano up tp pitch
>but I've always been a little leary of that.
>I'm wondering if they also have strings break on their second pass/
>fine tuning..
>
>I fully realize that they (the strings) are now at different spots on
>all of the contact and termination points so I would assume that
>would add to the puzzle.
>And I'd like to also add that it seems that the tork alone on this
>1/2 way-to-pitch, pitch raised piano feels MUCH higher than it did
>before (and more than "normal") and I chalk that up to the higher
>tension I have just introduced.
>
>I am a jerk tuner.
>
>(Stop laughing  :)
>
>I would be VERY interested in viewing the number of passes you folks
>do to bring a  piano up to pitch and whether or not you've
>experienced this-especially on ones that aren't so old.
>
>Hope this post reads OK- and I look forward to your responses!
>
>:)
>Michelle
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