Pianotech

  • 1.  Notching the low tenor in a concert grand or long piano

    Member
    Posted 23 days ago
    My bridge notching these days is pretty nice.  But I still struggle with the lowest octave of the long bridge in a long piano like a concert grand. On the rest of the bridge, the chisel, flat side down, 25 deg bevel on the chisel, is used at a fairly steep angle and works quite well, even on tough grain. However, those really long flatish notches at the low low tenor, require, at least the way I use the chisel, a flatter angle to traverse that very long notch. This tends to lift grain, for me, even with a razor sharp tools

    Checking out various youtube demonstrations, of course, they all show notching the easy part of the bridge....I see no demonstrations of this long notch area.   Some folks notch bevel side down, but I have never been able to control a cut with the bevel side down. I use rather short Japanese chisels

    Any perspectives on this particular part of the bridge?

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 2.  RE: Notching the low tenor in a concert grand or long piano

    Posted 23 days ago
    I'll bite.
    First of all, i successfully notch hickory, and i mention that because it can be trickier than maple. The shallow angles aren't necessarily better either. I use a lie Nelson chisel and have tried different angles but the original recommended angle seems best which is 35 degrees. If you are only razor sharp, then that could be the problem. It should be scalpel sharp!! Anyways if your chisel is sharp enough, then the notching will not be a problem. Sometimes in the hickory, i have to massage the notch by approaching from the side.
    Lie Nelson did a nice video of how to sharpen by hand with a proper chisel angle holder and a proper holding board for the stones. I went a little farther by making a leather strop and using automotive buffing compounds. Sometimes the wheel with red rouge is a quick touch up during the job. My chisel tip is pretty much a mirror. I also have a couple high quality logging chisels and just recently made a vertical Steinway style chisel for the vertical cuts (very nice to have). I got these from an antique store hear that has many old tools.
    Hope that helps.
    -chris

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    Chernobieff Piano Restorations
    "Where Tone is Key"
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Lenoir City, TN
    865-986-7720
    ------------------------------



  • 3.  RE: Notching the low tenor in a concert grand or long piano

    Registered Piano Technician
    Posted 23 days ago

    Use a longer handled chisel. First cut, at the saw cut line and tilt the chisel toward the saw cut and cut the full length of the notch so the width of the cut starts very narrow and widens to only about 1/4" at the end of the notch. Subsequent cuts starting toward the end of the notch and work back toward the pin line with each subsequent cut flattening the chisel gradually until the last stroke when the chisel should be flat as you make the cut at the pin line and you're just removing a very thin layer the length of the notch. 

    I use Japanese chisels and hone them frequently. 



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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
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  • 4.  RE: Notching the low tenor in a concert grand or long piano

    Member
    Posted 22 days ago
    Do you scoop at the start of the pin line, or just do a straight unscooped plane from beginning to end?

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



  • 5.  RE: Notching the low tenor in a concert grand or long piano

    Posted 22 days ago
    You can't just make a handle randomly longer, it will unbalance the chisel.  Plus leverage isn't the issue.



    ------------------------------
    Chernobieff Piano Restorations
    "Where Tone is Key"
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Lenoir City, TN
    865-986-7720
    ------------------------------



  • 6.  RE: Notching the low tenor in a concert grand or long piano

    Registered Piano Technician
    Posted 22 days ago

    Good question. I had to think about this. The first cut described there's no scoop. The following cuts that start out at the end of the notch there's also very little scoop-probably none at the first cut. As you work back toward the pin line there's progressively more scooping and the final cut that bisects the pin line has the most scooping. All done with the flat side of the chisel down.

    Re Chris's comment, I don't lengthen the chisel, I have several chisels of varying length and width. I find the longer chisels are easier for that section and because of the length of the notch the longer chisels also prevents me busting my knuckles on the edge of the bridge. I use shorter chisels for the treble section and bass bridge  I also tend to lay out bass bridges with the pin line perpendicular to the strings not a continuous bevel that produces non equal speaking lengths.  Not convinced you can hear the difference but I do it anyway, usually.

    Quality chisels are so important for this and I've found nothing better then the Japanese chisels. Good ones are quite expensive but worth it. 

    Of course you can also make a bridge notcher as has been discussed by Del and also Ron Nossaman. I've seen one in action at the Charles Walter factory. Very nice and very fast. 



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



  • 7.  RE: Notching the low tenor in a concert grand or long piano

    Member
    Posted 21 days ago
    Talking to a tech this morning, interestingly, they said they read in Mario's book that Fazioli notches from the side.

    I'm wondering if anyone has seen a video of this?  I've come in from the side, when grain direction on 90 deg quartersawn stock was impossible. But boy it takes eons and is not as clean as the other direction.

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



  • 8.  RE: Notching the low tenor in a concert grand or long piano

    Member
    Posted 21 days ago
    fazioli cutting notches from the side
      at 12:55

    although this still does not show the long notches...

    interesting jig just before this for cutting the bridge height notches

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



  • 9.  RE: Notching the low tenor in a concert grand or long piano

    Registered Piano Technician
    Posted 21 days ago
    Nice video.  So it looks like they make the first cut right at the edge of the notch taking minimal material.  The second cut removes the bulk of material but not at the pin line, the final cut establishes the cut at the pin line.  To do that for the longer notches would require a much wider chisel.

    Here's a video of the Steinway factory notching.  Note that they use basically a sharpened paint scraper and how flexible it is.  https://www.youtube.com/watch?v=PSZI5hGMThw

    And here's one that was uploaded by Nick Gravagne.  https://www.youtube.com/watch?v=q7b-UIJou3Q
    Notice the thickness of the bridge cap on this one.  One of the difficulties to overcome with the long notches is not going into the bridge root which, with classically very thin caps on Steinway bridges, forces you to scoop the notching in order to avoid that.  When recapping bridges planing down the bridge root so that you put a much thicker bridge cap helps to avoid that concern and allows you to cut the notch worrying less about how much you scoop.

    My older method of recapping was to remove the original cap in one piece, plug the old bridge pin holes and use the original bridge root height.  My current method is to plane down the bridge root and install a much thicker cap.

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



  • 10.  RE: Notching the low tenor in a concert grand or long piano

    Member
    Posted 21 days ago
    do you no longer fill the old pin holes?

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



  • 11.  RE: Notching the low tenor in a concert grand or long piano

    Registered Piano Technician
    Posted 20 days ago
    Oh no, I do fill what's left of them but if you put on a 1/2" cap there's less to fill (sometimes none) and less reason to worry about it.

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