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String calculator?

  • 1.  String calculator?

    Registered Piano Technician
    Posted 05-25-2024 21:55

    I ended up with this interesting old string calculating tool, but have no idea what to call it so I have no idea how to find out how to use it or even if it has any usefulness these days. Can anyone enlighten me?

    Thank you!



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    Tim Foster RPT
    New Oxford PA
    (470) 231-6074
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  • 2.  RE: String calculator?

    Registered Piano Technician
    Posted 05-25-2024 22:10

    It looks like one I have from Renner  I believe. It can calculate string tensions/lengths/sizes, also has functions for bass strings.

    As an apprentice, my job was to measure all the string lengths and calculate the tensions for all the unwound strings. Obviously before computers generated the first very thick hard copy readout of all that info.

    Not much good without the book; I'll see if I can dig it up.



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    Steven Rosenthal RPT
    Honolulu HI
    (808) 521-7129
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  • 3.  RE: String calculator?

    Posted 05-25-2024 22:36
    Hi,

    I have one, too...used it a good deal years ago before someone came up with the early computer modeling software. Perhaps Tremaine was involved in that?

    Agreed as to needing the book. Mine is probably around here...somewhere. It is, no doubt, quite "safe".

    Kind regards.

    Horace



      Original Message




  • 4.  RE: String calculator?

    Registered Piano Technician
    Posted 05-26-2024 01:12

    That is a TF65 or TF65/2 developed by Klaus Fenner in the 60's. I know 2500 were manufactured for retail sale between 1979 and 1981 and retailed for about 27.00 US. Ted Sambell sent me one of his as a gift many years ago. I do not have any instructions to go with mine. Klaus Fenner and Lothar Thoma collaborated on a book regarding its use but think it is in German and out of print. If anyone has any instructions in English I'd love to have a scan to go with mine which I thinks is just a TF65. Gregor Heller told me that they will still use one if they get string data for which they have not previously run the calculations.



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    Tremaine Parsons RPT
    Georgetown CA
    (530) 333-9299
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  • 5.  RE: String calculator?

    Posted 05-26-2024 05:42

    I have the German manual but I'm not sure if it's complete, send me an email at hzxasdf@live.com,I also sent instructions to Tremaine Parsons,The instruction manual is a section taken from a piano design book.Can anyone provide me with an English manual?



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    Zhanxi Huang
    Benxi
    86-18741420582
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  • 6.  RE: String calculator?

    Posted 05-26-2024 05:51

    TF 65/2 duplex slide rule : for figuring the lengths, diameters, tensions and inharmonicity coefficients of all strings for pianos, harpsichords, etc.

    There is also this book in the library, please go to this website 

    https://search.worldcat.org/en/title/17708195

    You go to this library to borrow this book。

    Or if anyone is interested, and is close to this library, you can borrow it.



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    Zhanxi Huang
    Benxi
    86-18741420582
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  • 7.  RE: String calculator?

    Registered Piano Technician
    Posted 05-26-2024 11:30

    Clicking more info at that link indicates a 31 page booklet and it also says that it is in English. Maybe someone posting here can find the booklet.



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    Tremaine Parsons RPT
    Georgetown CA
    (530) 333-9299
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  • 8.  RE: String calculator?

    Posted 05-26-2024 11:36
    Hi, Tremaine,

    I'm working on it...no promises.

    No fun to have such a tool; and to have "misplaced" the instructions.

    Kind regards.

    Horace




      Original Message




  • 9.  RE: String calculator?

    Posted 05-27-2024 18:12


    ------------------------------
    Zhanxi Huang
    Benxi
    86-18741420582
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  • 10.  RE: String calculator?

    Posted 05-29-2024 08:23

    book

    <<Fachkunde Klavierbau>>
    U. Laible

    P88-P102



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    Zhanxi Huang
    Benxi
    86-18741420582
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  • 11.  RE: String calculator?

    Posted 05-29-2024 12:42
    Dear Zhanxi Huang,

    That’s not a string calculator but a regular old slide rule. According to Wikipedia: 'a hand-operated mechanical calculator consisting of slidable rulers for evaluating mathematical operations such as multiplication, division, exponents, roots, logarithms, and trigonometry. It is one of the simplest analog computers.’

    Regards
    Arnold




  • 12.  RE: String calculator?

    Registered Piano Technician
    Posted 05-29-2024 22:20

    No, Sorry Arnold, it is a specialty slide rule developed by Klaus Fenner to determine proper string sizes/tensions for pianos and harpsichords called the TF 65 or TF 65/2



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    Tremaine Parsons RPT
    Georgetown CA
    (530) 333-9299
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  • 13.  RE: String calculator?

    Posted 05-30-2024 03:22
    Hi Tremaine,

    I am familiar with the T65, or rather the second version, but the image from the book "Fachkunde Klavierbau" written by Ulrich Labiel is a standard slide rule.

    Best regards,
    Arnold




  • 14.  RE: String calculator?

    Posted 05-30-2024 03:37
      |   view attached

    The T65 does appear in the book with examples on how to use it, but that's shown with a different image.

    Best regards,

    Arnold



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    Arnold Duin
    Krommenie NH
    31-75-6211529
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  • 15.  RE: String calculator?

    Registered Piano Technician
    Posted 05-30-2024 09:29

    OK, That may well be the case but this thread has been about the TF 65 or TF 65/2. BTW, would you happen to know the difference between 65 and 65/2?

    Respectfully,

    Tremaine



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    Tremaine Parsons RPT
    Georgetown CA
    (530) 333-9299
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  • 16.  RE: String calculator?

    Posted 05-30-2024 10:40
    Mr. Zhanxi Huang posted an image of a normal slide rule, to which I responded with a picture of the T65/2 from the relevant book. It seemed fitting for the topic. Unfortunately, I am not aware of the improvements made to the T65/2.
    I found online that Klaus Fenner first made a prototype, and later, at the request of the publisher Boschinsky, around 2500 units were produced by IWA.

    Regards, Arnold




  • 17.  RE: String calculator?

    Registered Piano Technician
    Posted 05-30-2024 11:10

    OK, I get it now. I missed the picture of the regular slide rule.



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    Tremaine Parsons RPT
    Georgetown CA
    (530) 333-9299
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