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I went to a house today that had a Yamaha Studio Piano where about 1/3 of the hammer return spring cords were broken. We've all seen them. To many clients, they can't tell the difference between a key with a broken cord and one that is still intact. Much like a broken or intact bridle strap. It often doesn't make any perceptible difference.

In this case, however, the two teenage girls really play and they have been complaining about "sticking keys" which actually translates to "poor repetition". The cords are broken randomly, so the young pianists encounter keys which "don't play" when they expect them to randomly as well.

This was a referral from the dealer I work for, so I contacted him. His first reaction was to tell the customer that the piano is useless but it is still quite a good piano that stays very well in tune and has good tone. It is their piano! They don't want a new one! "Can't you just fix those 'sticking keys'? That's all we really want."

So, the solution will be to replace all of the hammer butt flange cords. I have tried replacing the flanges before and that is impractical for two reasons: New flanges cost far too much and they won't really fit properly either and leave a nightmare job of realignment.

What is needed is a method for cord replacement that can all be done in a day's time at the house (without taking the action elsewhere). The clients don't want any down time on the piano. One day without it is enough.

I do not really have time for this, so I suggested that my apprentice, Lucas Brookins RPT do it and he is scheduled for January 6. We had spoken previously to his Technical Examiner, Dave Davis RPT about that kind of job and that it would eventually come up. Well, only a few months later and here it is! He had a fancy way of doing it that had been recommended by Bill Spurlock in year's past.

I suggested that all the dampers would need to be removed for access but Dave said that was not necessary. He had a way of quickly cutting all cords to the same length.

I would like to know from any other technicians who may have done this job whatever tips they may have. I promised to go there that day for my first period and get Lucas started but then, it would be up to him to get the job completed.

So, here are my questions:

• What general procedure would you use? Remove dampers or not? How do you remove the old material?
  
  
• What material to you suggest as a replacement? Heavy duty thread? Fishing line? If so, what gauge or test strength?
  
  
• What method do you use to make sure that each cord is cut to exactly the same length and what do you cut it with?
  
  
• What kind of tool do you use to press the new material into the slots?
  
  
• What kind of adhesive to you recommend to affix the new cord into place? How do you apply it?
  
  
• Would you take the opportunity to retension the springs and if so, how?
  
  

Thank you in advance for any experienced advice you may give. Please don't bother to say that you would have to charge more than the piano is worth. That would not be helpful in the least. That is why I am not doing the job. It's not worth doing to me. This is a job better left to a younger technician who needs full employment and can earn a day's wages from it.

I replaced a set of flanges once, and kept the old flanges and replaced the cords. So whenever I run into this problem, I just replace the flanges with ones that I have in stock.

To replace the cords, first, the old ones are rotten, so they just scrape out. I use some hemp cord that I got from a art supply shop which is used for stringing beads, but I think other materials would work as well. The problem is with cotton. Do not use cotton.

To cut them to length, I carefully wrap the cord around a piece of cardboard whose width is the length of the cord that I want. The coils of the cord should not overlap. Then I take scissors and cut them down the middle of the cardboard. The cord is the exact length, and nicely creased in the middle.

I use Elmer's tacky school glue for this. It holds well enough right away, so no clamping is necessary.

All in all, it is mindless entertainment, sort of like watching television, but far more useful!

Thank you very much, DBD! I am thinking that if I go to a fabric store and ask for the strongest, most resilient thread (nylon), I will get what is needed. Fish line curls. I too, was thinking that a small pair of very sharp scissors was the best cutting tool. I was thinking that once the length of thread is determined, one of those rulers with a slide could be used. You had made a gauge. Your idea was much like that I had heard of from Bill Spurlock but did not have completely in mind.

The glue you recommended was also interesting. NOT CA glue! Something that could soak into the thread after it is inserted into the groove just to hold it there would be sufficient. No toxic substances, any excess easily removed (like with a Q-tip).

Titebond trim glue works well for this too. Strong initial grab.

Someone had posted a method with a dremel to drill holes from the spring(?) side so that the hammers flanges never get taken off the piano. He used monofilament pushed in with glue.

It might have been Terry Farrell??? Anyone else remember?

Ron Koval

If the hammer butts have butt plates, it is a fairly easy repair.
Put the action in a cradle.
Remove the dampers, remove the hammer rest rail, loosen the hammer butt plate screws and let the hammers hang from the bridle tapes.
Scrape out the old cord with a piece of hacksaw blade.
Cut new cord to lengths by wrapping around a strip of cardboard and cutting. I prefer holding the cord tight with a straightedge and cutting with a sharp blade.
Glue the cords. I use medium viscosity CA for a quick set. Press the cord into the groove with a piece of wire.
Reassemble the hammers. The flanges have never been moved, so alignment is done.

If the hammers do not have butt plates, I prefer removing the flange from the rail, punching out the pin to remove the hammer, replacing the cord, repinning, returning the flange to the rail, and then realigning the hammers. No need to remove dampers for this. You may find it easier to realign the hammers before replacing the rest rail, but you will probably need to use the rail to support the hammers and wippens while putting the action into the piano, then take the rail out of the way.

Hi, Bill! I have a tiny bit of info to bring to the table. I ran into this problem shortly after starting to tune pianos for my friends, knew I'd be in over my head, and referred the job to a local tech. Then, I asked the tech what he did.

He used Northland brand "Bionic Musky/Pike Braid", gap filling superglue, and an accelerator. Here is the kind of fishing line:

http://www.lake-link.com/newproduct...-Fishing-Tackle-Bionic-Musky-Pike-Braid/

He said this cord is stronger than the factory replacement stuff and holds up better to humidity. Probably easy to find in Wisconsin!

--Andy

One further suggestion:
Moisture will accelerate CA glue. If you dampen the cord you can avoid the spray accelerator.

I think there was an article in the PTG Journal about this a couple of years ago, describing doing the job without unscrewing flanges. I'm abroad at the moment and don't have access to my Journals so can't check. Bass string maker John Delacour also had an illustrated article, but I can't find it on his website.

Hey Bill, Merry Christmas! For thread material look into fishing line used for "bait caster" type reels. One brand in particular is spider wire. It's braided, and tough as nails, but will never get memory in it like plain monofilament. This stuff is almost impossible to snap yet remains supple.

Once I asked the very same question in a German tech forum. In my opinion the best answer was this: change the flanges. Get the original flanges from Yamaha (or from a piano supply like Jahn in Germany). They are not expensive and they fit because they are original Yamaha. Then exchange the flanges, but only every second flange. That means, change the first flange and leave the second one. Then change the third one and so on. This helps to do the correct alignment. Then let the hammers travel. After doing so, repeat the whole procedure with the other half of the old flanges. For changing the flanges you have to put out the whole hammer/hammer but/hammer but flange unit.

If there are only some chords to exchange in field service, just put in a new cord. You can buy the cord in every piano supply shop. But it makes no sense in a Yamaha piano because you know that more chords will break in the future. In old pianos it may happen that only single chords break, but with Yahamas this is a systematic failure. To remove the old chord just scratch it out with a small screwdriver. Use any white glue like Titebond and press the new chord in the slot with a screwdriver.

Gregor

Wood glue to fix surgical thread as a replacement. Ibuse a piece of card wedged between the flange and loop sized from an intact loop as a template and a coping saw to clean out slots for new thread.

>What general procedure would you use? Remove dampers or not?
https://www.youtube.com/watch?v=k4XItZfiMIE (3:50-
http://okamotopiano.jp/?page_id=473
Details of the above typical YAMAHA method.
Hammer filing and reinstall new chord.It is completed in 120 minutes

>How do you remove the old material?
1:paint 100% alcohol or acetone　with brush on　the flange.
2:remove old material with following tool.
http://www.watanabemusical.com/products/details/index.html?id=jr1291367098

>What material to you suggest as a replacement? Heavy duty thread? Fishing line? If so, what gauge or test strength?
Genuine YAMAHA parts. T0102000
http://ameblo.jp/miurapiano/entry-10194212312.html

>What method do you use to make sure that each cord is cut to exactly the same length and what do you cut it with?
If you get Genuine YAMAHA parts then it's easy to cut the same length.

>What kind of tool do you use to press the new material into the slots?
tweezers　and thin metal scale.
http://www.itoshin.co.jp/products/find_input.php?find_mode=product&product_category1=%E8%AA%BF%E5%BE%8B%E5%B7%A5%E5%85%B7&product_category2=%E8%A8%88%E6%B8%AC%E5%99%A8%E3%83%BB%E5%AE%9A%E8%A6%8F&product_category3=%E3%82%B9%E3%82%B1%E3%83%BC%E3%83%AB

＞What kind of adhesive to you recommend to affix the new cord into place? How do you apply it?
glue for handcraft.
http://shibuhori.com/?pid=14870054

>Would you take the opportunity to retension the springs and if so, how?
I widen an angle and attach it

Thank you, Pro-TAK for your reply. Although my apprentice and I have already completed the job successfully in one day (along with other service requirements), your suggestions are the best and most complete I have seen so far.

I have one question: If "genuine Yamaha parts" are ordered, are the cord segments pre-cut and if not, what is the "easy way" you have to cut them?

I have photos of the job we did but it is far too difficult and time consuming to try to post them on here now. Somehow, I did not like the idea of "fishing string" as a replacement for the original cord. (Too stiff and too thin unless a thicker kind were chosen and then it would be far too stiff). Just not the right material. I found, at a fabric store, some 100% nylon thread that was the very strongest offered, intended for upholstery. We used a craft glue found at the same place, as you suggested.

We ended up detaching each hammer assembly and bridle strap so that we could work on each piece at a table. The re-installation of each hammer and flange assembly was a little slow but the alignment afterwards was not at all difficult.

There are many complications that can come with such a job. Your video shows deeply grooved hammers which I would agree must be reshaped with such a job as this. I had expected to need to reshape the hammers but in the end, the amount of wear was so slight and with time running short, we did not do that. The ultimate tone of the piano was very good and even in spite of that.

The complaint about the piano from the young girls who played it was about "sticking keys". We all understand that the client may call any key that does not respond as expected, a "sticking key". In this case, the accumulation of debris and remains of mice that had once been in the piano interfered with the free movement of the keys. Although the mice had done no real damage, the first operation to be done was to vacuum clean the keybed and lubricate the key pins, the key pin holes and key bushings. Now, the keys could all operate smoothly and evenly.

Another very serious complication that often occurs with such a job is hammer butt plates becoming loose and hammer center pins moving out to the side. Hammers may then rub against each other and therefore cause "sticking keys". There may be a severe and unusual wear pattern on the hammers that would certainly indicate the need to reshape the hammers. Fortunately, in this case, that was not a problem.

I had, in fact, taken care of this piano for many years. I had never looked under the keys, however. I had maintained the regulation and I may have even reshaped the hammers at one point. I do not remember if I did or not but if I did, that would account for the fact that marks on the hammers were very slight.

We found that all flange screws were tight but the wippen flange and and damper flange screws were re-tightened anyway. Each only took a small turn. So, in the end, there was no regulation needed. The piano itself was still so nicely in tune that a 30 minute tuning at the end was all that was necessary.

[Some of you may now want to say that complete record keeping of all services performed on each piano would have been in order. I would not disagree with that. But, as a technician just doing my work, that means even more work that most of the time, is never necessary. I usually remember most anything about a piano when I see it. I certainly had remembered this piano but I did not retain every detail about its service record.]

We found also that all of the hammer butt plates were very secure (due to my previous efforts with the piano). So, none of them needed to be tightened and there were no hammer center pins protruding outside the flanges.

In this case as well, the mute rail (operated by the center pedal) had a problem with the hole in the case on the Bass end. It had worn enough that the fixture for the mute rail slipped out of place easily. That caused the mute rail to sag low enough that the mute rail felt would catch some of the hammers intermittently. Another cause for "sticking keys!". The hole was repaired so that the fixture held in place normally.

Although the client was initially concerned about the price for an all day service, the lady of the house was very happy and satisfied at the completion of the job. She gave us more money than we had asked for! First, my apprentice, Lucas Brookins RPT played a piece that the girls recognized and were dazzled with the sounds and could see and hear that the repetition from the studio vertical piano was as good as could be expected from a grand piano.

It could have been a far worse situation! The pitch of the piano could have been far off. If, after repairs, the action could have needed regulation. The keys may have been unlevel. All of that may have taken another half day to remedy.

After completion of the job, the girls then sat down to play the duets that they knew and loved to play. The mother had tears of joy in her eyes as she heard them play and finally not complain about "sticking keys".

As part of the operation, we also did re-tension the springs as you indicated. When at rest, the spring stood out at about 80 degrees but after a quick re-tension operation (performed only with the fingers), the springs stood out at 90 degrees.

This was an example of how the piano owners loved their
piano. It had a good tone and it had always stayed in tune very well. The owner did not want to even think of replacing it! The person who paid the bill, (the lady of the house), was very happy to pay for the needed repairs and services so that they could keep the piano that was theirs and not seek to replace it.

In any case, such a piano may be traded in for a new one and what is a person who sells pianos supposed to do? Certainly not offer it "as is"! An ethical piano seller would do these repairs. It may cause a piano to be higher priced, for sure but if it had been acquired for little or no money, then the cost and time spent on repairs would be worth the investment.

There are many such pianos out there approaching 50-60 years in age but may have this singular problem to remedy. It is a good opportunity for a piano technician to work. A good method as you have offered is very much needed.

In home, vertical piano service quite often needs to be limited to one day at the price for that day's service. Otherwise, it is not practical for either the client or the technician.

Thank you again, Pro-TAK for providing the information necessary to complete such a job in one half, to actually one quarter of the time that many technicians have said it would take.

Dear Bill Bremmer .

＞I have one question: If "genuine Yamaha parts" are ordered, are the cord segments pre-cut and if not, what is the "easy way" you have to cut them?

Genuine parts T0102000 --- fine line --- easy to　put into gap　---　 well absorbable glue.
Please see following URL.

http://www.bbpianos.com/works/archives/252
http://negisi-san.blog.so-net.ne.jp/2012-06-14

Best regards
Pro-TAC (^_^)

Thank you, Pro-TAC,

The photos are excellent. However, since I cannot read the Japanese writing, was the cardboard tube from which you cut the cords included with the kit or did you make it yourself?

Spring cord will come supplied from Yamaha cylindrical form.
You just only cut it.

(ﾟ∀ﾟ)

I did that wotk last week. and so report it.
https://goo.gl/photos/WH7mQwtH2EZ3kCkA6

thanks pro-tac
what liquid did you brush on to help remove the old loops ?

athetone or 100% alchole.
I use 95%methyl 5%ethyl. It's for alchole lamp fuel.
please see the infomation detail each photo's.