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vertical damper lift rod repair

  • 1.  vertical damper lift rod repair

    Posted 16 days ago
    I looked at a 40-year-old Astin-Weight 45" console yesterday. The problem appeared to be a broken damper lifter rod hook that attaches the rod to the main action rail. The dampers were not being lifted evenly. The dampers closest to the pedal lever and the end of pedal lift rod were much earlier than the dampers farther away from the end of the lifter rod. When I pulled the rod, all of the hooks seemed fine. No broken hooks, all seemed firmly attached to the rod. And the hooks seemed reasonably aligned as I looked down the length of the lifter rod. So, what am I missing here? Do I need to bend the hooks at the base, where the hook is attached to the rod? If so, how to make the bend so that the lift will be earlier/later? It would seem that getting consistent bends in every hook would be difficult. Should I try putting a shim under the brackets that the hooks slide into?

    Perhaps the end hook is really broken, but not obvious. I'll have to recheck that. But if there are other causes to this uneven damper lift, I'd like to hear about it. I don't have a problem with bending damper wires, but as we know, bending wires doesn't correct the uneven lift if a hook is broken. I just don't see a break so I'm looking for other possibilities.

    Richard West
    Tucson, AZ

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    Richard West
    Oro Valley AZ
    520-395-0916
    440richard@gmail.com
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  • 2.  RE: vertical damper lift rod repair

    Posted 16 days ago
    Usually for me, three times, it has been the bracket that holds the hook

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    Larry Messerly, RPT
    Bringing Harmony to Homes
    www.lacrossepianotuning.com
    ljmesserly@gmail.com
    928-899-7292
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  • 3.  RE: vertical damper lift rod repair

    Posted 16 days ago
    Did you grasp the rod and try to separate it from the hinge pins?

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    Regards,

    Jon Page
    mailto:jonpage@pianocapecod.com
    http://www.pianocapecod.com
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  • 4.  RE: vertical damper lift rod repair

    Posted 16 days ago
    Richard

    This might sound like a no brainer, but did you check the action rail. Even a slight crack in will have the same effect as bent or broken hangers.

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    Willem "Wim" Blees, RPT
    Mililani, HI 96789
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  • 5.  RE: vertical damper lift rod repair

    Posted 15 days ago
    Wim, and All,

    Thanks for the helpful suggestions.  Keep'em coming!. All were scenarios I have never run into (loose/broken hinges, split main action rail, etc.) I'l be able to look at the piano again soon and will try out the various suggestions.  Thanks again.

    Richard

     






  • 6.  RE: vertical damper lift rod repair

    Posted 15 days ago
    Hey, wait a minute, Richard. What are you doing sticking you head in a piano.?  You're supposed to be retired, remember?.  Leave all those repairs to "real" piano tuners.

    BIG Grin.


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    Willem "Wim" Blees, RPT
    Mililani, HI 96789
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  • 7.  RE: vertical damper lift rod repair

    Posted 15 days ago
    Wim,
    A little consulting, a little teaching. A little tai chi. All between bike rides. And that was just today! Weather almost as nice as Hawaii, but not as wet.

    Richard



    Sent from my iPad





  • 8.  RE: vertical damper lift rod repair

    Posted 15 days ago
    Enjoy your retirement, Richard.

    See you in July.

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    Willem "Wim" Blees, RPT
    Mililani, HI 96789
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  • 9.  RE: vertical damper lift rod repair

    Posted 15 days ago
    One thing I've run into but I'm not sure if it would cause the symptoms you describe are trap levers that don't line up directly under the damper lifter rod. The further you depress the pedal the resistance from the action forces the trap lever to one side or the other so the travel is horizontal rather than vertical. The result being that the dampers don't lift off the strings. Sometimes this is caused by the trap lever not being installed correctly but some pianos with narrow cabinets just don't leave enough room for the lever to clear the plate struts and align with the rod up in the action. There are remedies for this though.
    The split action rails almost always occur on pianos where the sustain trap work goes to the right instead toward the bass on the left. The telltale sign of that problem is that the hammers go up when the pedal is depressed as the hammer flanges are attached to the part of the rail that is moving.
    You don't mention whether this piano has a bass sustain, if so does it exhibit the same symptom? Also did you check to see if the rod hangers (hooks) are snug in the rod? Perhaps one is riding up and down through the hole in the rod. Again not sure if that would cause the symptom.

    It always amazes me when I run into some new phenomenon that I'll just see once or twice out in over 40 years of work. Larry mentioned the broken bracket. I've seen two of those and the weird thing is that both were within 3 days of each other (about 30 years ago). Someone, I think Kimball, actually made them out of plastic, that was one of the two.

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    Steven Rosenthal
    Honolulu HI

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  • 10.  RE: vertical damper lift rod repair

    Posted 15 days ago
    Is it the bass or treble that lifts early?
    If it's the bass, this could be intentional to allow half-pedaling.

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    Ed Sutton
    ed440@me.com
    (980) 254-7413
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  • 11.  RE: vertical damper lift rod repair

    Posted 15 days ago
    Ed -
    I think 'faux-sostenuto' would be more accurate.  For half-pedaling you'd probably want it the other way around: bass lifting later.

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    David Skolnik [RPT]
    Hastings-on-Hudson NY
    914-231-7565
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  • 12.  RE: vertical damper lift rod repair

    Posted 15 days ago
    Thanks, All, for the responses. Most responders' comments seemed directed at the "hinges," so I'll look at those again. They seemed okay, but maybe I missed something.

    Ed, the piano does have a bass sustain, but what's happening is not, I'm sure, an intentional manufacturer feature. The top notes lift very early and then the rest lift in an arc that curves toward the tenor/bass break. The Astin-Weight is a unique design, to be sure, but this pedal system is not one of it's better design features. 

    Steve, your post describes the situation I'm seeing, i.e., the lift is on the right side, there's a split rod, and there's very little room for the pedal rod that comes up from the pedal lever at the bottom. The pedal rod may, in fact, be contacting the foot of the action bracket. It is very difficult to even get the pedal rod connected; there's not enough room to guide the pin into the lever at the top and working from the bottom it's hard to even see or feel where the pedal rod pin needs to go. The key bed is very close to the plate.

    I'm having trouble understanding one part of your email:

    The telltale sign of that problem is that the hammers go up when the pedal is depressed as the hammer flanges are attached to the part of the rail that is moving.

    Can you elaborate on that? The hammer flanges are "attached," i.e., screwed to the main action rail. Are you saying the main action rail is moving? I'm confused.


    Richard










  • 13.  RE: vertical damper lift rod repair

    Posted 15 days ago
    Action rails are often laminated, and if the glue fails, begin to split into two rails.
    The pressure on the damper rod causes the top half to lift up, lifting the hammer line.
    I believe this is what Steve is describing.
    I've seen it several times in small American console pianos.
    My sense of Astin-Weight is that they were put together imaginatively, but perhaps not fully tested by a large market in the field giving feedback.

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    Ed Sutton
    ed440@me.com
    (980) 254-7413
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  • 14.  RE: vertical damper lift rod repair

    Posted 15 days ago
    Richard

    As Ed said, what Steve is referring to is what I've experienced about dozen times here in Hawaii. The action rail, to which all the action parts are attached, are made from several planks edge glued together. It is not uncommon for one of those rails to be cut where the two edges are glued. When the glue joint fails due to excessive humidity, the pedal rod splits the rail.

    You might want to ask the customer where the piano came from.



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    Willem "Wim" Blees, RPT
    Mililani, HI 96789
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  • 15.  RE: vertical damper lift rod repair

    Posted 13 days ago
    Richard, as Ed and Wim describe. The action rail on many small American verticals such as Story & Clark, J&C Fischer, and a lot of the stencil pianos are made of two pieces glued together, due to the molding cuts, the width of the rail at the glue joint is a scant 5/8ths inch. They're usually compressed actions. The pedal rod is pushing upwards and the hangars convert that energy perpendicular to push the damper levers out away from the rail. That upward thrust is constantly pushing directly against (separating) the two glued parts of the action rail. If the glue joint breaks, starting at the point of most vertical thrust at the end of the treble, the upper part of the rail is pushed up and away from the lower part which is screwed to the action brackets. The dampers and hammer flanges are screwed to this upper part of the action rail so as it separates you can see the hammers rise vertically relative to the hammer rest rail.
    I think that the reason this tends to happen when the mechanism goes to the right is because the lifter rod is about a foot longer as it extends up to the treble end of the action this extra length adds greatly to the torque as the rod lifts the aggregate of 65 or so damper springs extending all the way down to the other end of the piano.
    Wim mentions that he has been seeing this problem since he came to Hawai'i. I didn't realize that it might be yet another phenomenon that is mostly limited to the tropics-like the expanding key leads.
    Usually the glue failure will extend to about half way down the rail but when I do the repair, in addition to regluing I use screws and/or dowels to reinforce the joint all the way down to the other end as the gluing is suspect. In fact I usually can't even see any of the old glue residue on the wood at all and it's a clean break along the glue line.
    If you remove the action and manually lift the dampers with the lifter rod you will immediately see if the action rail is separating.
    I still run into one or two a year but as these pianos are rapidly becoming landfill the problem is getting scarce. The last one I saw a few months ago I was able to convince the owners to replace Aunt Tillie's piano. I've been having luck by suggesting that Aunt Tillie got a really nice piano back in 1952 and she never would have an old piano like this one that is coming apart at the seams and maybe now's the time to start a new chapter of family history with an equally nice piano as Tillie started out with. Although I don't get the repair job, I also don't get the headaches and I can tune their new piano without parts that break just by looking at them.

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    Steven Rosenthal
    Honolulu HI

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  • 16.  RE: vertical damper lift rod repair

    Posted 13 days ago
    Thanks, Steve, and All for the thorough explanation. Sounds like what I've run into, although I'm not scheduled to see the piano for a week and a half. I'll let you know how things turn out.

    Richard








  • 17.  RE: vertical damper lift rod repair

    Posted 13 days ago
    Richard-
    Don't underestimate the labor it can take to make this simple repair.
    It can involve considerable parts removal, replacement and realignment.
    Probably worth it with an Astin-Weight piano.

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    Ed Sutton
    ed440@me.com
    (980) 254-7413
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  • 18.  RE: vertical damper lift rod repair

    Posted 13 days ago
    Ed, Wim, and Steve,

    I can see this could get "interesting." It will depend on how big a break is in the main action rail, and finding a way to stabilize the right end of the rail where the vertical pedal rod pushed up on the lever the the main damper lever lift rod. How bad are these rail splits usually? I'm thinking that the split needs to be opened up enough to work in glue. Perhaps a long dowel needs to be installed vertically, and a metal bracket screwed to the end of the right of the rail. Am I on the right track?

    Richard








  • 19.  RE: vertical damper lift rod repair

    Posted 13 days ago
    Richard

    The repair is relatively easy.  You don't have to remove all the action parts unless the whole rail has become unglued. You don't even need to try to squeeze in glue.

    The way I repair these rails is remove action parts around the action brackets, which should also be removed. Drill a hole through the action rail, and insert a bolt and tighten with a washer and nut. Takes about 30 minutes.

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    Willem "Wim" Blees, RPT
    Mililani, HI 96789
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  • 20.  RE: vertical damper lift rod repair

    Posted 12 days ago
    Expanding a bit on Ed's comment. On the cheaper actions one can expect some collateral damage as the flanges are also made with laminated pieces of wood. Economizing by using scraps I suppose. And they must have used the same disintegrating glue. So whatever whippen, hammer, or damper flanges you do remove there's a likelihood that a few will come apart in two pieces that need to be reglued or replaced.
    Btw, I do try to get glue in where I can with the 10 or so damper flanges I remove and it's very easily done in the high treble where there are no dampers and the most stress. I have some little blocks of wood with slots in them that go over the ridge molded across the surface where the damper flanges go for easy clamping. The greatest point of force is at the first hanger/hinge assembly which is about half way between the treble end and the highest damper and I put 7/32 dowels on either side of that. Note: the damper flange screw holes are offset to the hammer flange screw holes, both of which should be avoided.

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    Steven Rosenthal
    Honolulu HI

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