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Today's Dilemma

  • 1.  Today's Dilemma

    Member
    Posted 20 days ago
      |   view attached
    During a rebuild, the keyboard was replaced but the original action frame (split rails) was retained.  (?)   But at least it was painted gold.
    There is 1.5 mm difference in the action spread from bass to treble.  I'll shim to correct.
    The HCH is 1 mm difference b~t.

    To get 45 mm Blow Distance, the shanks rest on the felts (except #1)​. Notice the L/O button height between #1~2.​​
    The customer would rather I cut the felts than the wood. Constructing a jig, etc...

    Capstans align towards the rear of the cushion in the bass, center/front in the treble.
    After correcting the spread, I'll move the bass bracket back (maybe 1 mm) to position the capstans equally; this will also have the strike surface contact the bass strings better.

    How does it get out of the production facility like this? Last year, I had another re-re-do.  I am not impressed.

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    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
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  • 2.  RE: Today's Dilemma

    Member
    Posted 20 days ago
    <How does it get out of the production facility like this.

    the frame is an insane piece of engineering...literally.  Having rebuilt these frames for a while as a subspecialty, on precision, dedicated equipment, I have seen spreads all over the place as a normal condition, I can tell you how easy it is to solder the rail in the wrong angle or wrong xyz location. Plus, keep in mind, the extruded rails often have a twist end to end. If you use a rare straight tube, paired with a twisted tube, spread will wander wildly. In a production setting there is no way they would or could spend the time we spent setting these up to solder. In the factory, you've got some ridiculous about of time to position and solder, and then out it goes, accuracy be damned. The trick is to avoid QC'ing the finished frames.

    They spent a fair amount of time setting up a CNC to tightly broach the tube holes in the brass frames, a couple of years ago. But twisted extrusions, and tubes that bow after drilling are the name of the game, even with the CNC broaching. This means the entire frame takes on a twist, or can take off sometime in the first year, making bedding impossible without cranking the thing down and upsetting bedding. Split rails is another thing they have not been able to get a handle on in 150 years. This, mainly, because the fit of the tube/dowel, given the inside of the rail is not reamed, is impossible to get right anywhere near 100% of the time...plus, dowels move after drilling often as well.

    The whole thing, not even taking into consideration how the tube ears make alignment/travel  imprecise by design, is absolutely insane.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 3.  RE: Today's Dilemma

    Registered Piano Technician
    Posted 20 days ago
    But "We've done it this way for 150 years so why should we change now"?

    "Precision" is not synonymous with "accuracy".

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 4.  RE: Today's Dilemma

    Registered Piano Technician
    Posted 20 days ago
    Mr.Ialeggio,
    When you see that the machine that is used to make the rails still has a pulley on it from the time when the factory ran on steam driven belts you begin to understand.

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    Karl Roeder
    Pompano Beach FL
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  • 5.  RE: Today's Dilemma

    Member
    Posted 20 days ago
    Its called, being a victim of your own BS marketing.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 6.  RE: Today's Dilemma

    Member
    Posted 16 days ago
    After taking everything apart I was better able to make measurements. It turns out the the difference in action spread was due to the short-felted rep.
    I shimmed that out to make it even with the others (112.75 mm). The shanks are close to the felt and I might get by without having to trim. The overall problem was that it was purchased about 20 years ago, rebuilt. Nothing had been done to it other than tuning. L/O was 5~6+ mm, dip was ~11 mm.  Spacing hammers to the strings was difficult with the tubular rail, it will need constant tweaking. I had to move a few treble unisons.

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    Regards,

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