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Bridge re-cap on C.F. Stein with Sound Chamber

  • 1.  Bridge re-cap on C.F. Stein with Sound Chamber

    Posted 09-28-2022 21:58
    Hi guys, 
    I need advice on what kind of  plexiglass-vinyl to use to copy the pattern for bridge recap job. The sound chamber is part of the bridge so I need to make very price jig to notch it out so to speak. I've tried painters blue tape , but I was way off.    

    Thank you in advance

    Robert

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    Robert Vasiliauskas
    Wheeling IL
    (847) 220-1414
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  • 2.  RE: Bridge re-cap on C.F. Stein with Sound Chamber

    Posted 09-28-2022 22:40

    Simply map out the new pin placement once the new cap is installed. I never relied on the original being accurate, and chances are that it wasn't which may have caused its failure. Hairline cracks as seen in the second photo are the result of the usual stress placed on the cap.

    There are punches available once your center line is located. I made my own punches with a block of plexi-glass and bridge pins.



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    Regards,

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


  • 3.  RE: Bridge re-cap on C.F. Stein with Sound Chamber

    Posted 09-29-2022 12:02
    A thin plastic like this. Index it to the bridge root or something. I would use an ice pick as it finds the old pin holes easy. 
    Then when you put it on the new cap,, use a tool like Jon described to  punch the location, making adjustments so all the ducks are in a row and looking the same way. Drill and notch.
    Cap pattern.jpg



    Original Message


  • 4.  RE: Bridge re-cap on C.F. Stein with Sound Chamber

    Posted 09-29-2022 12:52
    Dale Erwin would probably ship you some. He has a large roll and is now Pianoforte Supply. 
    We have to thank Dale for keeping the options for quality rebuilding materials open.

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    Keith Roberts
    owner
    Hathaway Pines CA
    (209) 770-4312
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    Original Message


  • 5.  RE: Bridge re-cap on C.F. Stein with Sound Chamber

    Posted 09-30-2022 17:13
    Thank you , I've ordered polyester-mylar type of material for book covers. Which is 12" by 20 yards. From Amazon that should cover me for years to come. As far as the geometry for pins, is there more info on this subject . I would like to know more of the subject. Thanks 

    p.s. by the way there is a DVD on bolduc website about bridge recap. Would you recommend getting that?


    Robert

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    Robert Vasiliauskas
    Wheeling IL
    (847) 220-1414
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    Original Message


  • 6.  RE: Bridge re-cap on C.F. Stein with Sound Chamber

    Registered Piano Technician
    Posted 09-29-2022 15:42
    Jon,
    What’s your procedure for locating the center of the unisons on the bridge? It takes very little to make to make the side bearing too much or too little, it seems to me.

    Joe Wiencek
    NYC


    Original Message


  • 7.  RE: Bridge re-cap on C.F. Stein with Sound Chamber

    Posted 09-29-2022 17:00
    A thread/string drawn from the appropriate side of the hitch pin to the center of the agraffe. In the treble capo section it's a little trickier. You can either mark under the string or on either side; depending on the degree of side bearing you want and the thickness of the string. It should be a straight line from the hitch pin to the tuning pin broken only by the bridge pins; I read that somewhere.

    I might add measuring from the side of the hitch pin or center depending on whether it's a loop or tie-off to the agraffe or side of the tuning pin.

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    Regards,

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


  • 8.  RE: Bridge re-cap on C.F. Stein with Sound Chamber

    Posted 09-29-2022 17:03
    A unison punch might be better aligned with the mark under the thread/string unless you punch the front and rear separately (3-pin punch) to keep the pin line
    perpendicular to the wire.

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    Regards,

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


  • 9.  RE: Bridge re-cap on C.F. Stein with Sound Chamber

    Posted 09-29-2022 19:33
    Ahhh, Which hitch pin do you use Jon? There are 2 per note. Even if you go off the center wire side, there are differences. Unless the factory bridge pattern looks obviously out of place, I would go with what's there. Many times there was a reason it got done that way and it was not always lousy workmanship. What works in practice sometimes does not work in theory, 



    Original Message


  • 10.  RE: Bridge re-cap on C.F. Stein with Sound Chamber

    Posted 09-29-2022 20:22
    Whichever side of the hitch pin serves the center wire of that particular unison. Just because it was done that way at the factory doesn't mean it was supposed to be that way. It a long way between the drawing board and loading dock. One guy at a station might not get it quite right and the next guy doesn't send it back but makes due. Eventually, it might get compounded. Especially action geometry which is hit or miss.

    If there weren't room for improvement, our jobs would be rather boring.

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    Regards,

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


  • 11.  RE: Bridge re-cap on C.F. Stein with Sound Chamber

    Posted 09-29-2022 20:28
    On a scale that has all looped wires, there are three hitch pins for two notes. So it would be the left side of the hitch pin for C8, skip a pin and it's the right side of the hitch pin for B7; etc. But if the center wire happens to be a tie-off, it's centered on the pin.

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    Regards,

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


  • 12.  RE: Bridge re-cap on C.F. Stein with Sound Chamber

    Posted 09-29-2022 20:33
    It'll work out well if the hitch pins are drilled properly. Otherwise the unisons on the bridge are spaced evenly for appearances. It's usually fudged somewhere along the line.

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    Regards,

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


  • 13.  RE: Bridge re-cap on C.F. Stein with Sound Chamber

    Registered Piano Technician
    Posted 09-29-2022 19:33
    Thanks for detailing the procedure. Sounds simple, especially with practice.

    Joe


    Original Message


  • 14.  RE: Bridge re-cap on C.F. Stein with Sound Chamber

    Posted 09-30-2022 19:06
    With regard to improved bridge pin location it has been my experience that most of this improvement is to
    be found in the manipulation of string length. As to left right positioning, I would be cautious relying on hitch pin
    location as I've found these guys to not line up as nice as they could.
    Unison spacing typically has me looking at all factors then deciding on a first and last and maybe one in the middle of each section, 
    then 'fitting' the rest for best compromise.  I see tails show varying angles as they depart their rear bridge pin to find a hitch pin.
    That said, starting with a pattern is a very good idea, especially on ones first attempt, then make improvements as you see fit.
    Fenton

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    Fenton Murray, RPT

    Fenton
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    Original Message