Thank you all for tossing out your best ideas. So many responses, so little time!
Photos at end of post.
I apologize for any ambiguity when I said "note before treble break." It seems some people thought I meant the last note on the bass bridge. This piano has 3 sections of strings, and I refer to the strut between bass and treble bridges as the "tenor" break and the strut between middle section and higher treble as the "treble" break. Maybe that's not proper or consistent terminology and I should get my jargon straight.
So to clarify, this was the top note in the "middle section" of the piano, right before the plate strut separating it from the high treble. And it was the middle string in that note that was dropping suddenly. So no, it was not a single, wound string.
Also, I was always confused myself because people use becket to describe both the hole and the wire that goes into the hole. So I think now I'll use "tail" for the part of the wire that goes in the becket.
I only mentioned my PTG test results in the first post because I had already ruled out "faulty hammer technique" in my mind as the culprit and that was the only way I could think of to justify ruling it out. Three years ago I did a 30-50 c (bass to treble) pitch raise on this piano, and a few weeks ago I did a 5-15 c pitch raise. All other strings on the piano were stable. No way I could blame it on poor hammer technique. And I really don't want to get into the whole bending, flexing, messing with tuning pin controversy. I was taught to set the pin (straighten it out because the part of the pin outside the hole twists, especially when pins are very tight - and this has been demonstrated to be true) and use firm test blows to even the tension among all the speaking and nonspeaking lengths of strings. It works for me. Any other theories or techniques ... I would want some engineer type to show me experiments that demonstrate how they work.
Back to this Baldwin.
I had already squeezed the wire against the pin, even tho the slight gap there was no more than on many other pins on this piano (which were not slipping).
I had already checked to make sure no string was binding against a pressure bar screw, but the middle string COULDN'T be binding against that anyway.
Of the theories I got as feedback, I considered the most likely suspects to be:
- Binding at the hitch pin (because of the plate being bumpy, the hole for the hitch pin being recessed, and there being a sharp upward rise of the string against a sort of V bar molded into the plate just above the hitch pin. The wire definitely could not ride up on the hitch pin (see photos).
- Tail of wire not long enough in the becket, and wire working its way out. However, I should have seen that gap at the becket get bigger if that was happening between visits, and I didn't. But still ... who knows?
I liked the idea of filling the recess around the hitch pin hole in the plate with epoxy to try to keep the string from getting pulled into the recess, so I got some quick setting epoxy to take with. I borrowed back my stringing box, which I bequeathed to my "protege" a couple of years ago, so I would have the right tools and supplies whether just rejiggering existing string or replacing it.
So on trip 4 (trip 1 was tuning a few weeks ago, then 2 more to pull up string) here is what I found and what I did. I will give my conclusions, such as they are, at the end.
I backed out both tuning pins enough to pull wire off hitch pin. This required more than the usual backing out because the hitch pins had been bent down towards the plate at the factory. You can see this in some of the photos, and that the pins have been pounded down by a hammer. When I could see the hitch pin without the string around it I realized that, because of location of the hitch pin (sort of behind the keybed) and the pin being bent down, even if I used the end of an opened up jumbo paper clip to try to get epoxy around that hole, there was no way I could clean the epoxy up tidily and it might make a rougher surface than the plate already was. So I dropped that idea.
Then I checked the bridge pins. Well, the top RIGHT bridge pin was completely loose. But that was not the string that was dropping in pitch! The other bridge pins on that note were all tight. But I epoxied that bridge pin in.
After the expoxy set, I decided to try to keep the existing string, but put about a half turn more on one pin and a half turn less on the other, which would move the part of the string that might have been binding under the hitch pin over a little. At the suggestion of one of you, I put a thin balance rail felt punching on the hitch pin, also to try to prevent binding against the plate.
I got the right tuning pin (not the problem string) turned some, pushing the tail back into the becket every time it started sliding out. Once I had the coils on that one tight enough to not slide around, I started on the middle tuning pin. And guess what? The tail of the wire had broken off when I was backing the pin out!! Was it too short? I don't know. Maybe it broke because I had to turn the pin so far counterclockwise. In retrospect, I should say that on this Baldwin, on some of the tuning pins the wire was obviously poking out the other side of the hole, but on this particular pin it was not. I didn't use a piece of wire from the open side to see how far the tail was in the becket, but I'll remember that idea in the future.
At first I felt I would need to put a new string on. But I was not looking forward to going back to pull it up over and over. So I did something I've never done - I flattened out the end of the coiled wire, pushed it into the becket, and crimped it around the pin. I figured if it broke when I tightened the wire, I wouldn't be any the worse for it. It was worth a try. I was already not planning to have exactly 3 coils on each pin anyway, so what the heck?
I made sure there was enough wire in the becket that I could feel it poking out the other end and that it didn't pull back as I worked on getting the coil tight, etc. Tuned up both strings and checked neighboring strings (still almost perfectly in tune).
That was Thursday around 4:30 pm. After the last two attempts at just pulling up the string, the owner texted me within an hour saying the string had dropped significantly in pitch.
The result this time: owner texted me Friday morning saying "So far so good" and hasn't contacted me since. (It is now Saturday night.)
As a person who likes to know the "why" of everything, I know the scientific method would say make only one change at a time if you want to know which thing worked. I did not want to keep going back trying one idea each time so I did a couple of things and we don't know for sure which of them worked.
Would the result have been the same if I had:
just glued in the loose bridge pin, even tho the problem string was not against that pin?
just lowered the strings but not so far as to take the string off the hitch pin and then just retuned, as the Yamaha person suggested?
left out putting the felt punching at the hitch?
not noticed or corrected the loose bridge pin?
Sadly, we will never know. But I think the problem is corrected.
As evidence that this piano was not Baldwin's finest hour, I include a photo showing a slathering of glue on top of the bridge in a totally different (higher treble) section of the piano, and a string on the note just above the treble break that shows notches in it from some kind of mishandling.
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Barbara Barasa
Ashland OR
541-552-9349
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Original Message:
Sent: 10-09-2019 00:28
From: Barbara Barasa
Subject: Baldwin Hamilton - one "string" drops suddenly in pitch, but not on test blows
I am calling this piano a Baldwin Hamilton because that's what I know it as. Label is Baldwin, but I've always thought of the "flip top" studio pianos (with built in lid prop) as Baldwin Hamilton.
Anyway, I tuned this piano once 3 years ago, did 30-50 cent pitch raise, no issues. However at that time no one was really playing the piano. Now the owner is taking lessons and practicing every day.
Tuned the piano 2 weeks ago and almost immediately the owner emailed me to say one note was very out of tune. I was out of town then but went to see the piano the day I returned (2 days ago) and one "string" of the three strings on the F# just before the treble break had dropped VERY noticeably. I thought maybe I had committed some terrible oversight and left it that way when I tuned it but owner said it was perfectly in tune when she first sat down to play it, but quickly went out of tune.
Weird. Piano is in perfect like-new condition. Hammers barely worn, tuning pins SUPER tight like a new piano. I am extremely rigorous with test blows. (Passed my PTG tuning exam at over 90% with entirely aural tuning back in the '80s.)
So I pulled up the middle string, whacked it hard with a bunch of test blows. Nothing changed, and I told the owner I had no idea what had caused the string to drop and that I have never encountered this before (which is true). I had no theory, but told her to let me know if it happened again. She texted me that night and said the note went out of tune shortly after I left.
The owner is a woman of about my age (73) and is the only one playing the piano. She is definitely not a pounder, plus I DID pound it and nothing happened!
Went back yesterday. Only possible thing I could think of was that no matter how hard I pounded my test blows, the string was getting "hung up" with friction somewhere. The weird thing is, why only on that half of the wire? The middle "string" is the same wire as the right "string", but right string is unaffected!
On that theory (friction somewhere along the string) I took the action out to see if there was any obvious problem (no), dropped a little ProLube at all the bearing points. In doing so I noticed that at the hitch pin end, the strings all rise up sharply from the hitch pin and run across a sort of high bearing point on the plate - a plate that is not smooth but very bumpy/rough finish - before reaching the bridge. Also, each hitch pin goes thru a hole in the plate and it seems to me the string kind of gets pulled around the hitch pin and down into the recess of the hole - an opportunity for a lot of the string to bind. Put lube there too.
Then pulled up the string, set the pin, pounded like crazy. Told her if it happened again, I would post it to the forum.
She texted me and said she sat down to practice and about 15 minutes after I left the string dropped again.
My next attempt at a solution will be to replace the string. And lube all bearing points before putting the string on.
But before I do that, maybe there is an Baldwin dealer of yore out there who has encountered this kind of thing who can offer advice. I used to do warranty and warehouse tunings for Baldwin in Chicago in the '80s, so it's not like I never tuned a Baldwin piano.
Any other suggestions?
Barb
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Barbara Barasa
Ashland OR
541-552-9349
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