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replace trichord agraffe and save the strings?

  • 1.  replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-05-2022 21:37
    Hi Everyone,
    I have someone asking me whether I can save their trichord strings during an agraffe replacement on G3 below middle C on a grand.
    I can see saving one string but not all three easily. Even that one string is going to have to be either a knot situation or a way to preserve some structural integrity of that string whilst threading it through a new agraffe. I don't like old string when I do this repair because its more brittle and breakage prone after any manipulation. I'd prefer to put new string in and do the careful work of stabilizing the wire as best as possible, and then stopping by to tune up frequently to keep everyone super-happy.
    As far as clipping and knotting more than one string on a unison in an area where there is not much space from tuning pins to the downbearing felt leading down to the agraffe, it would be pretty tight I'd say. I wouldn't be thrilled to do it. But I'm not generally a knotty or naughty person.

    Have you ever saved all three strings during an agraffe replacement? And if so, what dark magic did you use? LoL
    Thanks, I appreciate it.

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    Tom Wright, RPT
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  • 2.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-05-2022 21:59
    Greetings,
       It is my normal to keep the original strings when an agraffe is replaced.  I take them off the pin, clip the becket off and then pull them straight by putting a rod in the coil and pulling it towards me.  Keep the old agraffe on the strings to keep them orderly.  
       Thread them through the new agraffe and make a coil on a dummy pin.  Install and pull up to pitch.  It helps to keep even tension on the strings when pulling them up so that you don't cause the wire to "migrate" around the hitch or bridge pins, causing more instability than otherwise. 
    Regards, 
    Ed Foote RPT





  • 3.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-09-2022 02:40
    I agree with Ed on this one.  No need to replace strings.  I do pretty much the same method as Ed. Except, 95% of the time, I'm able to bend the becket out slightly, just enough to feed it back out of the agraffe.  (I know that weakens the becket and it will be more likely to brake with time.  But I've been doing it for years and so far no problems.) Then feed through new agraffe,  on to the dummy pin, recoil. and back on to  old pin.  Keeps the piano sounding the same with all old, dingy strings, and note is way more stable...
       Question: How does everyone like to remove the agraffes?  I carefully get a hole started with a small drill bit and then drill down into the brass.   If the agraffe doesn't just come out when I back out the bit, I just use an easy out and done. Occasionally, I'll find the demon agraffe that is really embedded in the plate, that requires more, but rarely..

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    Matteo Crudo, RPT
    DC Piano Co.
    dcpianos.com
    Berkeley, Ca.
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  • 4.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-09-2022 06:42
    Funny that I'm right in the middle of replacing an agraffe.  I'm just soaking up the comments.  My patient is a Steinway D at UCSD, currently being used mostly as a "prepared" piano. 
    Regarding removing the stem, I've tried a lot of the traditional ways with various degrees of success.  My most reliable method is a left-handed drill bit.  The first bit I used was fairly small, and it was just drilling a hole and not "catching".  I went up a size, and it just started backing itself out.  Cheap bits from Harbor Freight in a nice little case.  The hardest part is getting the bit centered.  I wish they made a left-handed Grab-bit, which works great for removing stripped screw heads.

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    Paul McCloud, RPT
    Accutone Piano Service
    www.AccutonePianoService.com
    pavadasa@gmail.com
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  • 5.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-09-2022 09:53
    The hardest part is breaking a bit in the agraffe stem....
    N Salmon, RPT





  • 6.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-09-2022 10:44
    "The hardest part is breaking a bit in the agraffe stem....:

    Or, a hardened E-Z-out.  I have successfully removed them with this problem by taking several of the smallest grinding bits in a Dremel tool and spending 15 minutes letting them grind down through the brass and steel.  It took three bits last time.  Two hands, paying attention to the vertical centering, and light pressure.  When the last of the steel is powdered, the sound and feel instantly changes, at which point a reverse drill will take the remainding brass out.  
    Regards, 
    Ed Foote RPT
     





  • 7.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-10-2022 08:15
    Left-handed drill bits are also useful for this purpose.

    Bob Anderson
    Tucson, AZ




  • 8.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-06-2022 00:21
    I have replaced an agraffe with original strings, though I did it more on a personal dare.

    Today I replaced a Steinway agraffe and installed two new strings (tenor #17).  Rather than bother with tuning I did a touch up and schedule a return in two weeks.

    I just wish I knew why its often Steinway agraffes that break.

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    Blaine Hebert RPT
    Duarte CA
    (626) 795-5170
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  • 9.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-06-2022 05:51
    Thanks for reply!
    Its one of two things or both: imperfections in the brass agraffe alloy at the time. and secondly, overtightening which weakens the agraffe because it puts it under tremendous additional tension.

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    Tom Wright, RPT
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  • 10.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-06-2022 11:31
    John Zeiner, Sr. did a class with a deep dive into that question.
    Maybe he'll respond.
    Ruth Zeiner

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    Ruth Zeiner
    ruth@alliedpiano.com
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  • 11.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-07-2022 00:26
    The reason they break is because the old Steinway agraffes are improperly threaded and the threads stop short of the top of the stem. That, combined with the flat bottom of the seated portion, puts stress on the stem joint which is where they fail. Always replace agraffes when restraining. The new agraffes have a somewhat different design.

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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
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  • 12.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-07-2022 13:42
      |   view attached
    Here are some photos with notes. There will be a part 2 which will be a separate email.
    John

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    John Zeiner RPT
    Allentown PA
    (610) 437-1887
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    Attachment(s)

    docx
    Why agraffes break.docx   22.98 MB 1 version


  • 13.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-07-2022 13:44
      |   view attached
    ​This is part 2, related to stress fractures.
    John

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    John Zeiner RPT
    Allentown PA
    (610) 437-1887
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    Attachment(s)

    docx
    Why agraffes break 2.docx   10.08 MB 1 version


  • 14.  RE: replace trichord agraffe and save the strings?

    Posted 07-07-2022 16:47
      |   view attached
    Here is a photo of the threading problem provided by Ron Nossaman.

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    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
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  • 15.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-07-2022 13:24
    The only S&S agraffes I’ve ever seen break are the ones with the stem not threaded all the way to the shoulder, Blaine. The serial # range is somewhere between 220,000 and 280,000. Isaac Sadigurski documented a more precise # range.

    Bob Anderson
    Tucson, AZ




  • 16.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-06-2022 00:51
    Last time I had to replace an agraffe I seriously did not want to have to replace the strings. This is what I did, and there have been no problems. Knowing how to do a string splice can save you a lot of time and aggravation. 

    saving the strings with an agraffe replacement


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    Geoff Sykes, RPT
    Los Angeles CA
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  • 17.  RE: replace trichord agraffe and save the strings?

    Posted 07-06-2022 11:09
    Hi Tom,
    The last time I replaced an agraffe (Steinway L) I replaced the strings, as well. When and if this happens again, I will try to straighten the original strings and reuse them. It will take two years for a new string to stabilize. And, because one of the new strings will probably be shared with an adjacent note, the stabilizing issue becomes even more apparent on that note's unisons. Splicing the strings would work and still be more stable than a new string but that seems like even more work. In my case, the client lives an hour away which doesn't help matters.

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    Randy Prentice RPT
    Tucson AZ
    (520) 749-3788
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  • 18.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-08-2022 12:39
    Splicing is my preferred method as well. 

    Ed F.: It took me about 5 readings of your post to figure out WHAT you were talking about. I finally got it though. Not bad, but I'd still splice probably. 

    Peter Grey Piano Doctor

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    Peter Grey
    Stratham NH
    (603) 686-2395
    pianodoctor57@gmail.com
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  • 19.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-08-2022 15:15
    I am a little confused about why one would splice a string as part of replacing an agraffe?? 
    Regard,s 





  • 20.  RE: replace trichord agraffe and save the strings?

    Registered Piano Technician
    Posted 07-08-2022 18:04
    In my case it was 100% because I didn't want to have to replace the strings and cause instability on two adjacent notes. I've tried breaking the becket and straightening the leftover string for a new coil, as Wim suggested, but for me the splice, as I posted, was SO much easier and didn't require any callbacks to touch up those notes.

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    Geoff Sykes, RPT
    Los Angeles CA
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