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Chinese spec piano makeover

  • 1.  Chinese spec piano makeover

    Member
    Posted 03-03-2021 09:42
    I've got a Chinese grand 5'3" spec makeover  that we are starting on. It's getting WNG shanks/Rosnen Bacons, Long bridge and bass bridge new caps, some soundboard work, and correction of Chinese counterbearing clue-less friction configurations (it will be compliant to tune), Paullelo wire and new Bass strings of my design....a Falconi.

    My quandary:

    Sales price, for 5'3" Chinese instrument will I think be limited to what I can get, even with a real nice sounding instrument and responsive action, and compliant tuning friction...meaning 10K tops, I think. This limits how much work we can do. I am prioritizing the work outlined above because I know that will improve the sound of this thing by an order of magnitude, in the biggest bang for the buck department. Pin torque is perfect...no reason to touch it (bushed pins #1 pins).  I need to remove the plate for the bridge/soundboard work. I don't want to touch those perfectly fitting pins. I know I could get the plate back on later with the original pins still installed, and install new bushings (I have an idea how to do this, which allows me to compress the bushing over the already installed pins).

    The question is, can I get the plate off while the original bushings are in place? The stretcher is  removable...we will remove that today.  I'm thinking, with the chain hoist lifting, and the stretcher out of the way, we, in theory, should be able to pry the tuning pin section of the plate away  from the block with the bushings still installed. Any thoughts on this?

     ​

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 2.  RE: Chinese spec piano makeover

    Member
    Posted 03-03-2021 11:07
    Interesting idea. Perhaps you can use some machinist jacks or small bottle jacks placed in different sections to provide an even slow lift of the plate . Maybe you need to lift from above using some type of bar the width of the plate with lift straps. A gantry crane instead of a chain hoist may be worth investigating. Since the pins have a slight angle going into the block that will need to be factored in . Maybe there is a way to fabricate a device that is like a forklift to get in under the plate but above the pinblock ???

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    James Kelly
    Owner- Fur Elise Piano Service
    Pawleys Island SC
    843-325-4357
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  • 3.  RE: Chinese spec piano makeover

    Registered Piano Technician
    Posted 03-04-2021 11:24
    I would just keep my fingers crossed that the pinblock is not glued / doweled in , but just screwed into the plate and shelves.  If the stretcher comes off, that's a good sign.  You may possibly be able to just remove screws on the outer edges that screw the plate down through the pinblock to the shelves and pull the plate out with the pinblock still attached.  Otherwise, possibly using some sort of jack at the front in conjunction with a hoist to gently pry the plate off the pins , at the right angle could work.  Best of luck!
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    -Matt Crudo, RPT 
     





  • 4.  RE: Chinese spec piano makeover

    Registered Piano Technician
    Posted 03-03-2021 11:45

    Jim,

    I hope you come up with some good ideas to remove the plate, My question is whether you can install new bushings around the existing tuning pins without breaking them. Plate bushings are under outward stress from the tuning pin and under inward pressure from the plate. I foresee all the plate bushings breaking as soon as you drive them around the tuning pin.



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    Roger Gable
    Gable Piano
    Everett WA
    425-252-5000
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  • 5.  RE: Chinese spec piano makeover

    Member
    Posted 03-03-2021 12:22
    Check out Rigging.com there are many different types of jacks, air bags, hoists, straps to look at however maybe it would not be a bad idea to consult a qualified rigger about your plan. Getting the plate out and back in so as not to destroy the tuning pins will be tricky but probably not impossible. maybe some jigs using guide rails/tracks can keep the plate aligned.

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    James Kelly
    Owner- Fur Elise Piano Service
    Pawleys Island SC
    843-325-4357
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  • 6.  RE: Chinese spec piano makeover

    Registered Piano Technician
    Posted 03-04-2021 18:06
    You many not have to separate the pinblock from the string frame. Chinese makers do this in different ways, but you should be able to remove the screws at each end--those that go into the inner rim--and lift the whole thing out intact.

    ddf

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    [Delwin D] Fandrich] [RPT]
    [Piano Design & Manufacturing Consultant]
    [Fandrich Piano Co., Inc.]
    [Olympia] [WA]
    [360-515-0119]
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  • 7.  RE: Chinese spec piano makeover

    Member
    Posted 03-04-2021 19:00
    That would be nice, and would be my favorite preference. I can however, unfortunately, see the edge of a large countersunk hole, peeking out past and underneath the plate edge right by the case side on both treble and bass. So that says to me, there is something large screwed in there, under the plate. Also the PLate screws at the corners seem to bisect the edge of the rim, so I'm guessing they only go into the block. However, that's easy to prove, tomorrow we'll back them out and see how long they are. Still, if it turns out there are screws under the plate, with a multi tool, I could slice that, as long as the screws are not hardened.

    I'll pull one of the other screws, and see if the shank is hardened

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 8.  RE: Chinese spec piano makeover

    Registered Piano Technician
    Posted 03-03-2021 12:20
    Is the pinblock attached to the case sides?
    If not (just hoping), you may be able to pull out the plate with block attached.

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    Ed Sutton
    ed440@me.com
    (980) 254-7413
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  • 9.  RE: Chinese spec piano makeover

    Member
    Posted 03-03-2021 13:50
    Pinblock is epoxied in on the ledge. I could deal with that, but there are screws also into the rim, that I can see, underneath the plate. So we ditched that plan. RE installing bushings after the fact, I have an idea on that. Make a tool the OD of the bushing and long enough to fit over the pin, that slightly compresses the bushing. Make a second tool as a ram that fits over the pin but is machined to contact the bushing. So you force the compressed bushing over the pin. I think it might work.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 10.  RE: Chinese spec piano makeover

    Member
    Posted 03-03-2021 15:23
    Too much work for experimentation which is of dubious success.  Just remove the pins, ream the holes and install 2/0' pins. Stringing will go faster too with new pins.

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    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
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  • 11.  RE: Chinese spec piano makeover

    Registered Piano Technician
    Posted 03-03-2021 23:30

          Wow! 220 places to bind. In addition to hoist I'd consider putting upward pressure directly on the plate flange from supported keybed as wedges can only be tapped in on the stretcher side.

            What's back up plan if the web cracks? If it lifts easy fine. Otherwise hear Jon, #2s are not so bad. As James cautioned, the pins are angled (the wrong way).

            Now that I think about it, how can the plate flange move that way if it's presumably already tight against the front of the block? Hmmm? It may be a non- starter. I don't know….. Good luck if you try it. Hey, hey!

    Paul




  • 12.  RE: Chinese spec piano makeover

    Registered Piano Technician
    Posted 03-04-2021 00:16
    Drill out the bushings with Pianotek #BSE-2?

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    Floyd Gadd
    Regina SK
    306-502-9103
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  • 13.  RE: Chinese spec piano makeover

    Member
    Posted 03-04-2021 07:35
    Interesting.  I have made custom boring bits before, using tubing...its actually pretty easy...I may give this a try...hmmmm...

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 14.  RE: Chinese spec piano makeover

    Member
    Posted 03-04-2021 15:08
    Don't over-think the procedure. Keep It Simple...

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    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
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  • 15.  RE: Chinese spec piano makeover

    Member
    Posted 03-04-2021 15:10
    Over Engineering, not because it's expedient but because we can.

    It's the age old question, "Can I or Should I."

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    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
    ------------------------------



  • 16.  RE: Chinese spec piano makeover

    Member
    Posted 03-04-2021 17:42
    What are the huge phillips type screw heads on these Asian plates. Are they in fact phillips?  I don't think they are Pozidriv. Just ordered a no. 4 phillips, and no 3 Pozidriv, but I think its larger than that.​

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 17.  RE: Chinese spec piano makeover

    Registered Piano Technician
    Posted 03-04-2021 19:10
    I'm with Jon, just restring with 2/0 pins.

    My .02

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 18.  RE: Chinese spec piano makeover

    Member
    Posted 03-05-2021 20:18
    We jumped ship and pulled the pins. Turns out, as I surmised, the block was not only screwed with two quite large screws to the rim, accessible only underneath the plate, but there was also a tuning pin in there as a dowel. Forget that. Tried prying up against the bushings briefly...forget that one two. Oh well, so much for the perfectly fitting previous pins...sigh. I buried my sorrows and went skiing.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------