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J.F Harris and Co. Square grand. teaching myself how to be a piano tech I have so many questions.

  • 1.  J.F Harris and Co. Square grand. teaching myself how to be a piano tech I have so many questions.

    Posted 05-24-2022 11:51
    To start I had no idea how pianos work until I got this piano. but I am not afraid to teach myself new things.

    Had the chance to get this square grand piano, My wife fell in love with it, most of the keys did not work but I said how hard can it be ... *que laughing* If anyone has any information on this particular brand that would be swell, so far my research has taken me to that they were a piano retailer and maybe had someone else make these for them. They won some awards at the 21st Ohio state fair best square piano silver medal. found in the 26th annual report of the Ohio state board of agriculture.

    So far I have replaced the back rail felt, balance rail felt, front key felt, hammer rail felt, replaced all the thread on the jacks, replaced all the dampers, (not period accurate dampers as i have learned after reading many threads on here), I fixed one damper arm on the piano.

    what I still need to do is replace the 2 last missing treble hammer assemblies, eventually replace all hammers and all strings. For right now I am just trying to get this to play well enough for my wife to enjoy, I have done two tunings on the piano so far at A435 seems to hold tune well just still slightly flat (piano has been sitting for many many unknown years)

    Questions I have. I have a substantial gap below the nameboard and the keys, as well as when the key is depressed the key sits 1/8 to 1/4 above the front rail cloth and the jack is just pressed up against the jack stop button. and I get roughly a little less than 3/8 key dip so far. MY guess is the back rail cloth is too thick that I got as the piano had little to no felt so I had no examples to go off of. If I add more punching's to bring the key height up I will have even less key dip. I am just unsure where to start to get this piano as good as I can knowing it will not be perfect.

    Below is a link to all photos I have taken so far and will update the album as i add more.

    https://photos.app.goo.gl/THusKDZwQXLghkxe7

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    Joshua Sharp
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  • 2.  RE: J.F Harris and Co. Square grand. teaching myself how to be a piano tech I have so many questions.

    Registered Piano Technician
    Posted 05-24-2022 13:19
    Joshua.

    First of all, my "condolences" to you for taking on a project like this. Very few full time piano technicians even bother working on square grand pianos, much less doing any major repairs. So kudos for that. 

    Second, your wife is going to owe you "big time", for encouraging you to tackle this job in the first place. At least when you get done you know you can keep it. 

    Now, to the technical part. Again, the first thing I would do is get a solid door, 3' x 7', to put on your table so that the action will sit flat. Having the ends of the keyframe dangle over the edge of your table makes it very difficult to do any kind of regulating. When I did a job like this, even I had difficulty regulating the action on a large, and I had a big, flat work bench. 

    Now to the exact question you asked about. Key dip is the first step in regulating an action. You said there is a gap between the tops of the keys and the rail across the keys. (I saw the picture). That is the first step you should do. Key height and key dip are a balancing act. You need enough back rail felt and balance rail punching to lift the keys up high enough to get a little more than 3/8" key dip, (filling ion the rest with front rail punchings). But not high enough not to allow the rail to go across the keys. Since you didn't have a sample of the back rail cloth, you have to experiment with different thicknesses. You want to keep in mind that you also need a thin felt balance rail punching under the middle of the key. 

    Once you've got those dimensions figured out and working, then the fun starts, regulating the action. 

    Wim