Pianotech

  • 1.  Sohmer Cupid restringing

    Posted 04-11-2021 21:30
    Hello, I am a new member of the community and I write from Italy, so I excuse in advancefor my english.
    I am not a professional piano technician but during this last year when I had so few possibilities of having a normal life and so much available time, working on pianos has been one of the things that allowed me to keep a decent mind equilibrium.
    Some months ago I found an ad of an used grand piano for about 500 usd (obviously it was in euros), and I bought it without hesitations. Sometimes I can be very impulsive.

    It was a 1927 Sohmer Cupid, the keyboard was half stuck and the pedal lyre and the music desk were missing, but the soundboard was in good condition, the bridges were ok, all the strings were at their place and the general appearance was acceptable.

    I had never heard of Sohmer before, and as I checked later, these pianos are essentially unknown in European market.
    When I could extract the keyboard and the action (not easily, as many hammers were stuck in high position) I realised that the keyboard problem was worse than I could imagine, as the leads were heavily oxidated and had forced the keys to literally explode.

    So I removed the leads, had to rebuild many keys and to repair all the others by inserting wood gussets and gluing them together, pressing the wood fibers with clamps to have back a correct key shape.

    The hammers were grooved but had never been reshaped before, so they could get back an acceptable shape and functionality, and the action was in very good conditions and just needed a good registration.
    It took some time to restore the cabinet but now the worn and scratched surface has been substituted by a high gloss black paint, the new pedal lyre is at its place and also the new music desk is ready.

    I was amazed about the construction quality of the piano and proud of the general result of the restoration, but the sound quality had not satisfied my expectations.
    The sound is quite brilliant, as one can expect from the bridge agraffes, and the sustain is very good, but the low tenors and the last five bichords in the basses sound really horrible.
    This leaded me to the decision of restringing the piano.
    I bought the Travis book, so I have the original scales, but I read in many previous posts that this piano model has some of the worst scales in the story of piano making, so I don't think it would be a good idea to restring it repeating old mistakes.
    I read that an important improvement would be to add four or five wound bichords in the low tenor section, and change most of the strings gauges, in order to have a more even tension.
    I also read about pianos like this restringed with hybrid scales using Paulello wires with different breaking point characteristics, obtaining very good results.
    I planned to buy a scales calculating software and I will, but I think that I am still too inexperienced on scales parameters to have immediately safe results from it.
    I wouldn't like to restring the piano  with poorly calculated scales, so I think that for this first time it is better to ask help from someone with more experience.
    I think that this is not a new problem for any of the members of this community and that this model of piano has already been restringed successfully many times.
    May someone help me?
    I thank you all in advance for any suggestions, that will be greatly welcomed.

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    Fabrizio Loi
    33100 Udine
    Italy
    +39338 4444485
    fabrloi@yahoo.it
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  • 2.  RE: Sohmer Cupid restringing

    Posted 04-11-2021 21:55
    Welcome,
    One of my worst rebuild experiences was with one of those many decades ago. I went a little further than you and had replaced the strings (i copied the original scaling and used Mapes bass strings). I also had put new Ronsen Hammers. And it sounded not so good. My current thinking is the bridge agraffes just produce too nasal of a sound for my liking.  If i was to rebuild another, i would also try the Paulello wire, and Abel Naturals to try to sweeten the tone.

    -chris

    ------------------------------
    Chernobieff Piano Restorations
    "Where Tone is Key"
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Lenoir City, TN
    865-986-7720
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  • 3.  RE: Sohmer Cupid restringing

    Posted 04-12-2021 10:00
    Thank you for your replay.
    I agree about the nasal tone, but I realised that with some hammers voicing the tone could be greatly improved. 
    Unfortunately in the mid/low section of the keyboard, from F2 to E3, the issue is too great to be solved that way.

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    Fabrizio Loi
    33100 Udine
    Italy
    +39338 4444485
    fabrloi@yahoo.it
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  • 4.  RE: Sohmer Cupid restringing

    Posted 04-12-2021 13:05
    hello Fabrizio.
    I have bought several sets of used sets of hammer assemblies from Lindeblad to use on old pianos when the customer did not want to go with brand new hammers. Some of their sets are in very good condition. 
    I think their website is lindebladpiano.com:  ask for Eric.
    Of course, you have to do some measuring of the original hammers and make sure that what they have, will fit your piano.
    Peter

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    Petrus Janssen
    Peachtree City GA
    678-416-8055
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  • 5.  RE: Sohmer Cupid restringing

    Registered Piano Technician
    Posted 04-11-2021 23:21
    Fabrizio

    You did an amzing job restoring the piano, especially the lyre. Congratulations. 

    Regarding the keys. The leads weights are in the keys to help balance them, and give proper touch to the keys, You might find that it won't play very well without adding some weight back in them.  This is a delicate operation, and you might need help doing that.

    As far as the sound of the piano is concerned, changing the scale is not going to make a significant difference. The problem is the agraffs on the bridge. That is what makes the tone sound the way it does, especialy in the low tenor.  

    The bright sound is produced by the hammers. I would suggest you replace the hammers with Abels.

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    Willem "Wim" Blees, RPT
    Mililani, HI 96789
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  • 6.  RE: Sohmer Cupid restringing

    Posted 04-12-2021 10:09
    Dear Willem, thank you for you reply and for the appreciation of my efforts.
    I posted the pictures of the keys without leads but that was an intermediate step of the restoration. 
    I already re-balanced the keys to 51 grams and the keyboard is actually very pleasant to play.
    I agree about the hammers, I could voice them down a little bit and now the tone on the main bridge has been improved, but unexpectedly the worst notes, from F2 to B2, are all on the bass bridge, that has traditional pins, so I hope that a better calculation of the bass scales, together with new hammers, can improve the final result.
    P.S.
    Also I am very proud of the pedal lure, thank you for remarking it.
    :-)

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    Fabrizio Loi
    33100 Udine
    Italy
    +39338 4444485
    fabrloi@yahoo.it
    ------------------------------