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ivory whitening experiment

  • 1.  ivory whitening experiment

    Posted 08-11-2020 19:57
    I did an experiment with Ivory. I placed this single piece in direct sunlight and recorded the number of total hours of exposure. Nothing else was done to it.  The conclusion is that is became 50% more white during the first 16 hours, but to achieve another 50% increase in whitening required 48 additional hours of direct sunlight exposure.






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    Gary Howell
    Buckeye Piano Tuning
    Massillon OH
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  • 2.  RE: ivory whitening experiment

    Registered Piano Technician
    Posted 08-11-2020 23:30
    Thank you Gary so very much for doing this work and posting it!

    Question. When you say 16 hours or 24 hours do you mean hours of a day or actual daylight exposure?

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    Edward McMorrow
    Edmonds WA
    425-299-3431
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  • 3.  RE: ivory whitening experiment

    Posted 08-12-2020 08:12
    the hours were counted as actual sunlight exposure. So 24 hours equals the ivory laying on my driveway from the moment the first rays hit the driveway until the sun dips below the trees on the western edge of our property, and then again the next day and the next, while adding up the hours to reach 24, or 48 or 64 hours.

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    Gary Howell
    Buckeye Piano Tuning
    Massillon OH
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  • 4.  RE: ivory whitening experiment

    Posted 08-12-2020 10:08
    Great data points Gary, thank you!



    - Jonathon





  • 5.  RE: ivory whitening experiment

    Registered Piano Technician
    Posted 08-12-2020 00:16
    Dear Gary

    Looks wonderful, thank you for sharing. 

    A brilliant tip. 

    Elizabeth

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    Elizabeth Pearson
    Gaithersburg MD
    240-751-5900
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  • 6.  RE: ivory whitening experiment

    Registered Piano Technician
    Posted 08-12-2020 09:15
    Thanks for this - especially since I thought direct sunlight turned ivory brown.
    Nancy Salmon, RPT





  • 7.  RE: ivory whitening experiment

    Posted 08-12-2020 10:13
    Why does your hand also get lighter?
    -chris

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    Chernobieff Piano Restorations
    "Where Tone is Key"
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Lenoir City, TN
    865-986-7720
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  • 8.  RE: ivory whitening experiment

    Registered Piano Technician
    Posted 08-12-2020 16:28
    I wonder if ultra violet lamps would do the trick.

    Meanwhile, here's a story about Prat Read's all glass ivory bleach house. They put them in the sun for 21 days.
    http://deepriverhistoricalsociety.org/about-drhs/bleach-house/

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    Steven Rosenthal
    Honolulu HI
    808-521-7129
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  • 9.  RE: ivory whitening experiment

    Member
    Posted 08-12-2020 16:45
    UV (black light) tubes work well.  Typically 14 days of 6 a.m. - 8 p.m.  The benefit is that there is no heat so ivory on the keystick does not loosen even with repeated (light) applications of 40 peroxide.  I have one set up that is a four foot workbench portable unit and another that I can hang from the ceiling.  I keep the bulbs about 3-4 inches above the ivory.

    --
    5 Tarr's Lane WEST
    Rockport, MA  01966
    978-546-8428





  • 10.  RE: ivory whitening experiment

    Registered Piano Technician
    Posted 08-12-2020 17:25
    I found this exhaustive history of ivory key making and bleaching here, it's free to read with a registration.
    https://www.jstor.org/stable/40968261

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    Steven Rosenthal
    Honolulu HI
    808-521-7129
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  • 11.  RE: ivory whitening experiment

    Posted 08-12-2020 17:28
    Thank you Steven, I don't have access. Can you PDF it?



    - Jonathon





  • 12.  RE: ivory whitening experiment

    Registered Piano Technician
    Posted 08-12-2020 18:07
    Jonathon, actually if you click the x on the "log in through your library..." box covering the page there's a button to read it free online. They have the same prohibitions that our journal has, also their online version isn't clear enough to make a pdf. It's worthwhile, about 26 pages plus pictures. 
    The registration is very brief.

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    Steven Rosenthal
    Honolulu HI
    808-521-7129
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  • 13.  RE: ivory whitening experiment

    Posted 08-12-2020 21:32
    I felt it was important to take each day's photo under the same light source in my workshop. But using only an iphone to take photos, I did the best I could.

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    Gary Howell
    Buckeye Piano Tuning
    Massillon OH
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  • 14.  RE: ivory whitening experiment

    Registered Piano Technician
    Posted 08-13-2020 07:00
    I have done the same as Debra, with good results as well. Good to know that I can do it without electricity though. ☺

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 15.  RE: ivory whitening experiment

    Member
    Posted 08-13-2020 07:09
    Peter, Around here it's good to know that I can do it without sunshine!
    Deb

    --
    5 Tarr's Lane WEST
    Rockport, MA  01966
    978-546-8428