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Verdigris Experiment

  • 1.  Verdigris Experiment

    Registered Piano Technician
    Posted 30 days ago
    Looking for participants for a verdigris experiment.  If you have action parts that are contaminated and wish to participate here are the procedures.  I'm interested to see if this procedure is effective and long lasting.  Use Steinway discarded hammer flanges that are affected by verdigris.

    1.  Get six shank and hammer flange assemblies, the nastier the verdigris the better. Label them A, B, C, D, E and F. Measure the strike weight and modify so that each assembly is equal (somewhere around 9-10 grams SW preferred).
    2.  Measure the resistance of the flanges with a gram gauge and record the data.  Also swing each assembly and record the number of swings (if any).  Hold the hammer at 3:00 and if it swings to 9:00 that's one swing.  Back to 3:00 is two swings.  Each swing counts until the hammer stops moving.
    3.  Soak the hammer flanges in a narrow necked jar filled to cover the flange with Goof-Off.  You might want to put some foil over the mouth of the jar to slow evaporation and check to be sure the flange remains covered for the required time.
    4.  Soak A, B and C for 24 hours and D, E and F for 48 hours.
    5.  Once the flanges are dry, test again with a gram gauge and swing test and record the data.
    6.  Put them in a paper bag and store somewhere for 6 months and measure again.

    Email me the initial data (after soaking) and, if you can remember, send me the data after 6 months.  davidlovepianos@comcast.net

    Note: Goof-Off is toxic so take necessary precautions.

    Thanks.

    Your data chart should look like this

      SW  Before soaking (g) Swings  After soaking (g) Swings   After 6 months (g) Swings
    A (24)                
    B (24)                
    C (24)                
    D (48)                 
    E (48)                
    F (48)                



    ​​​​

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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
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  • 2.  RE: Verdigris Experiment

    Member
    Posted 29 days ago
    I am interested in doing something like this but have had my own ideas on what I want to use as the treatment. Maybe I can follow your protocol to some extent . I am not sure how many S & S  assemblies I have but if you have six you can send me with nasty verdigris I will follow your procedure to the letter and be a tester. One thing I am wondering about is how to measure and modify the strike weight to get 9-10 grams

    In step 2 it may be good to clarify how you measure the flange resistance with the gram gauge - ie where you put the gauge.  also I was taught to measure the swings by holding the flange at 12 oclock raise the hammer felt to 3 oclock and let it swing.Any swing past 6 oclock counts as a swing.

    A client here has an S&S and the hsf where replaced however there are problems with the whippen flanges. New whippens where installed but the flanges where reused along with verdigris bushings. I am not sure if they repinned and rebushed but there was a ton of either talc or teflon all over the place.

    Susan Kline sent me a bunch of old verdigris Steinway HSF but i did not begin to do anything. Maybe I can follow my plan and you yours and in 6 months check/compare results ... If I have 12 I will do a split test...

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    James Kelly
    Owner- Fur Elise Piano Service
    Pawleys Island SC
    843-325-4357
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  • 3.  RE: Verdigris Experiment

    Registered Piano Technician
    Posted 29 days ago
    Since the probable cause of the verdigris is acids from the fats used in the original treatment I have often wondered if an ammonia treatment wouldn't neutralize the acids.  An ammonia and detergent solution might remove enough of the fats and neutralize the acids enough to eliminate the verdigris.

    Its an easy enough experiment!

    Current Goof-Off is orange oil and is probably not very toxic.

    The old Goof-Off formula was mostly xylene which was though to be very toxic.  It was actually a contaminant of the xylene that was dangerously carcinogenic and that was removed, but Goof-Off went with orange oil which is considered non-toxic (anything is toxic in a  large enough concentration).
    ------------------------------
    Blaine Hebert
    Duarte CA
    626-795-5170
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  • 4.  RE: Verdigris Experiment

    Member
    Posted 29 days ago
    My bottle of Goof-Off had a sludge formed around the base of the cap. So when it dries it gums up. I discarded it because CBL is more effective in removing labels and their glue residue.

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    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
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  • 5.  RE: Verdigris Experiment

    Registered Piano Technician
    Posted 28 days ago

    Not sure what kind of goof-off you had but the original formula doesn't do that.  There are several different Goof-off products.  The one I'm interested in is this one.  It does not gum up when it dries.  I think you were likely using some other product.

     

    https://goofoffproducts.com/wp-content/uploads/2017/08/ProStrengthRemoverMSDS.pdf

     






  • 6.  RE: Verdigris Experiment

    Registered Piano Technician
    Posted 29 days ago
    My own experiments show that goof-off works quite well for this when the parts are soaked (the original formula, which is quite toxic--I don't know about the orange oil stuff).  I'm looking for others to perform the experiment as well.  I understand that people have their own opinions and treatments.  I'm not interested in that right now.  If you can perform the experiment great, if not, that's fine too.  I don't have enough parts to send them out to everyone.  I figure those who do action rebuilding may have these parts available to them.

    https://www.ewg.org/guides/cleaners/5686-GoofOffProfessionalStrengthMiracleRemover/

    ------------------------------
    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
    ------------------------------



  • 7.  RE: Verdigris Experiment

    Registered Piano Technician
    Posted 29 days ago
    I use engine starting fluid (the kind with ether in it). That, combined with vigorous joint working and serious compressed air, cleans it up good. However, it ALMOST always comes back.

    Didn't we determine that it was the paraffin dipping that caused this?  I think it was James Kelly that produced an advertisement by SS where they actually admitted to this.

    It seems that post clean out, followed by a pre-cut, rolled SS center pin (to eliminate exposure to open copper alloy) would be the best solution if replacement is not an option.

    My .02

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 8.  RE: Verdigris Experiment

    Registered Piano Technician
    Posted 28 days ago
    There is little in paraffin that could cause corrosion (In chemistry, paraffin is used synonymously with alkane, indicating hydrocarbons with the general formula CnH2n+2.  see Wikipedia, paraffin:  https://en.wikipedia.org/wiki/Paraffin_wax).

    On the other hand, natural fatty acids such as tallow and vegetable oils contain an acetate group, which is essentially vinegar and can cause formation of copper acetate which is green (https://en.wikipedia.org/wiki/Copper(II)_acetate).

    Treatment with ammonia should produce ammonium acetate (https://en.wikipedia.org/wiki/Ammonium_acetate) which should be less corrosive.
    Add a little detergent and the verdigris should wash out with water.

    I doubt that an oily solution such as orange oil kerosene or naphtha (lighter fluid) would work.  I watched a dealer dose dozens of corroded Steinway actions with many, many cans of lighter fluid followed by baking them in the sun and it never worked.  You aren't removing the acids.
    A better solution is to replace the parts!


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    Blaine Hebert
    Duarte CA
    626-795-5170
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  • 9.  RE: Verdigris Experiment

    Registered Piano Technician
    Posted 28 days ago
    Yes, I agree with replacement usually.

    So, the acids are in...the cloth?  Now the rails turn green also. What would bring this about?

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 10.  RE: Verdigris Experiment

    Registered Piano Technician
    Posted 27 days ago
    It was probably the wood that was treated, but the treatment would wick into the bushing cloth eventually.
    Any treated wood that is in contact with brass (or copper) would eventually turn the brass green.

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    Blaine Hebert
    Duarte CA
    626-795-5170
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  • 11.  RE: Verdigris Experiment

    Registered Piano Technician
    Posted 27 days ago
    David,

    That Goof off MSDS looks "wonderful".  ☺

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 12.  RE: Verdigris Experiment

    Registered Piano Technician
    Posted 28 days ago
    Household ammonia is diluted with water which introduces another element into how the bushing will respond.  Anhydrous ammonia (99% pure) is very toxic to breath the fumes.

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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
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  • 13.  RE: Verdigris Experiment

    Registered Piano Technician
    Posted 27 days ago
    My own "treat and keep the part in a bag for a year" experiment showed good results with.....
    (drum roll)...
    Rain-X.
    Haven't tried in real-world conditions though.

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    Scott Cole, RPT
    rvpianotuner.com
    Talent, OR
    (541-601-9033
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