Pianotech

  • 1.  Re-stringing and pinning after CA treatment

    Posted 04-18-2021 13:24
    I have recently had the question posed to me of re-stringing a non-bushed
    piano that previously had been treated with CA for loose pins.
    Would there be adverse ( or any ) side effects from the CA treatment with regards to pinning up the old pinblock.
    I do remember a plate that I actually had to knock loose from the block from a previous treatment, not a big deal, I cut that block out as I usually do so I have no real data.
    Thank you,
    Fenton

    Virus-free. www.avg.com


  • 2.  RE: Re-stringing and pinning after CA treatment

    Member
    Posted 04-19-2021 10:20
    Hi Fenton,
    I would think there would be positive effects. Repinning a failing old block is going to cause problems. You might find inconsistencies in feel due to the different amounts of CA that got in the hole. Then again you are going to find inconsistencies in an untreated old block.
    Basically the CA is glue sizing the top of the hole where a flagpole tuner damaged it. Since the pins aren't jumpy with CA, I like it.
    Addition of glues to a laminated pin block would seem to be a plus. Gluing the block to the plate would add stability,,, lol,,
    CA glue is becoming widely accepted in piano use. There was an initial skepticism.
    The negative effects are the complaining you hear from some rebuilders though we all know each piano is different, even ones built in the same year.
    So we have to try and see what works no matter. The plus of using a drill bit to clean the hole and the larger lo-torq pins would even out the feel. There are other options.
    There might be a few hassles you weren't prepared for when repinning but we develop our methods and then the only difference in time is due to how much complaining you do.
    Didn't factories use to dip the pins in Varnish when installing in a new block?  A few at least?


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    Keith Roberts
    owner
    Hathaway Pines CA
    209-770-4312
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  • 3.  RE: Re-stringing and pinning after CA treatment

    Registered Piano Technician
    Posted 04-19-2021 12:55
    I would simply tell the client (unless YOU are the client) that it is slightly uncharted territory and the job should (in theory) last just as long as an "untreated" block. But don't guarantee anything. 

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 4.  RE: Re-stringing and pinning after CA treatment

    Posted 04-20-2021 13:01
    Dear Peter and KIETH,
    Thank you for your kind replies.
    Would love more data, or educated opinion on the subject.
    Fenton

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    Fenton Murray, RPT

    Fenton
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  • 5.  RE: Re-stringing and pinning after CA treatment

    Member
    Posted 04-20-2021 18:34
    Real data that correctly indicates the cause of any failure would be very difficult.
    When you take a block that has failed enough to be treated and drive new pins in it,, is any subsequent failure due to: the larger pin, the block continuing to fail or the off chance some Ca glue around the pin accelerated the failure.
    First I would toss out #3 as the reason, when you consider the other factors. That amount of CA glue most likely would have minor effect on the hole holding the pin. If there was that much room around the pin that excessive glue got in there,,, then I would say the block was shot to begin with and never should have been repinned. CA glue will not withstand a metal pin driven in. I think of it as rosin. Kind of a sticky granular. Sure beats sandpaper in the hole.


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    Keith Roberts
    owner
    Hathaway Pines CA
    209-770-4312
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  • 6.  RE: Re-stringing and pinning after CA treatment

    Posted 04-21-2021 13:19
    Here's a closely related question.  I'm about to tackle a c. 1965 Yamaha C3 with severe rust on the strings.  It's a university instrument, one of a pair that had the same problem.  I've restrung the first one, and it turned out very well indeed.

    The budget situation is unusually fragile/uncertain at the moment, so I'm planning to run an experiment on the existing bass strings, adding a step to a protocol I learned from a video series by Craig Hair.  I'm going to soak them in Evapo-rust, then wash them out in household ammonia, followed by a vinegar rinse, water rinse, blowing out with compressed air, and then will dry them out in an aluminum pipe with a blow dryer at the end.  I've done this once before without the Evapo-rust step, and ended up with a set of serviceable (not "like-new"!) strings.  I will either end up a set of usable strings and some education, or just some education.

    In any case, I will be restringing this piano.  I will be upsizing the tuning pins by one size.  I don't remember whether the sister piano I did a couple of years ago had 7.0 mm pins (.0272 inches) or something closer to 1/0 (.0276 inches)  I may be upsizing to 1/0!  In any case, I face the prospect of stringing the bass again with the existing set, then replacing with new at some point in the perhaps not-too-distant future.

    I figure I have three options for bass tuning pins:
    • Restring with the new size, then, upon replacing the bass strings later, reuse the same pins without removing them.  This will involve a level of working the pins on the later restring that may leave them looser than I want them.
    • Restring with the new size, then up size again on the later restring
    • Swab the holes in the bass section with CA before restringing, and use the original pins, then up size when I do the later restring.

    Any thoughts on these options?  I am planning to lift the plate out of the piano to service the bridge, so leaving the original pins in place in the bass section is not an option I am considering.

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    Floyd Gadd
    Regina SK
    306-502-9103
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  • 7.  RE: Re-stringing and pinning after CA treatment

    Registered Piano Technician
    Posted 04-21-2021 15:58
    Floyd, considering the labor costs associated with preserving the old bass strings (and later replacing them again), is there really much savings over a new fresh set? Also, I've observed in the past that reusing tuning pins can lead to breakage owing to heat etc. from extracting them.

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    Steven Rosenthal
    Honolulu HI
    808-521-7129
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  • 8.  RE: Re-stringing and pinning after CA treatment

    Registered Piano Technician
    Posted 04-22-2021 12:46
    Keith,

    Am I missing something? You refer to #3 and a large gap, but nowhere do I see them mentioned in the discussion thread.
    To what are you referring?

    Thanks!

    Dave​

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    Dave Conte
    Owner
    Knoxville TN
    817-307-5656
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  • 9.  RE: Re-stringing and pinning after CA treatment

    Member
    Posted 04-22-2021 13:26
    I gave three options for subsequent failure. Number one driving in a larger pin. Number two the block had failed then continued to get worse. Number three, the CA glue. Out of those three reasons for uneven or loose pins after re-pinning , which do you think is least likely to cause failure?
    Sometimes there is a huge gap along one side of the pin. I suggest in that situation repinning is not the best option. Whether or not CA glue had been used

    Sent from my iPhone