I have a Wagner upright piano with a Herrburger-Brooks action. The action has a metal lever, or tongue, that is on the left side of the action and projects toward the front of the piano. The tongue is shaped roughly like a small spoon with the "hollow" side facing up.
The soft pedal contacts the tongue via a long vertical wooden rod. At the top of the rod, there is a block of wood that is "cantilevered" toward the front of the piano so that it can touch the tongue.
When the soft pedal is pushed, the rod rises and the block lifts the tongue.
However, the block doesn't lift the tongue high enough to move the hammers as close to the strings as I think they are designed to move.
A local piano tuner worked several days on this piano a few years ago, and it appears his solution to the movement problem was to glue a stack of felt on top of the block of wood. This fell off about a year ago, and it is only this week that I began to seriously think about the question of how that tongue is supposed to be lifted.
I am now wondering if the action and the piano were originally together. If they were a unit, then I have to wonder whether the soft pedal mechanism has been somehow modified.
Soft pedal and Herrburger-Brooks action lever problem
Moderators: Feg, Gill the Piano, Melodytune
Probably is an original action but just bad design.
Firstly don't overlook the obvious. Is there an adjustment on the pedal in the form of a nut which can be tightened to take up some freeplay ? (I'm assuming not if your tuner took a few days to help sort the problem). Next examine the pivot point of the rocker in the bottom of the piano which transmits pedal movement from pedal to the vertical rod on the left side of the cabinet. Is it intact? Excessive movement here (especially unwanted side to side movement) can reduce the amount of lift.
If all seems to be adjusted as well as can be expected, the thing to do is to remove and refit the pedal rocker altogether, moving the pivot closer to the pedal to increase the lever ratio of the small pedal depression distance to make a larger lift distance at the rod end.
Easy peasy.
Firstly don't overlook the obvious. Is there an adjustment on the pedal in the form of a nut which can be tightened to take up some freeplay ? (I'm assuming not if your tuner took a few days to help sort the problem). Next examine the pivot point of the rocker in the bottom of the piano which transmits pedal movement from pedal to the vertical rod on the left side of the cabinet. Is it intact? Excessive movement here (especially unwanted side to side movement) can reduce the amount of lift.
If all seems to be adjusted as well as can be expected, the thing to do is to remove and refit the pedal rocker altogether, moving the pivot closer to the pedal to increase the lever ratio of the small pedal depression distance to make a larger lift distance at the rod end.
Easy peasy.
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sussexpianos
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Staircase "solution"
Well, I had a small block of wood and I glued that to the top of the original block of wood. Now the two blocks of wood look like the beginning of a staircase, but they seem to be doing the job of lifting the spoon-shaped lever. Hope it all holds-up without collapsing like a house of cards!
The pedals were both correctly adjusted with no freeplay to speak of.
Moving the rocker pivot was a good idea, but I didn't understand what was meant by it until after I glued-on the second block of wood!
The pedals were both correctly adjusted with no freeplay to speak of.
Moving the rocker pivot was a good idea, but I didn't understand what was meant by it until after I glued-on the second block of wood!