Pianotech

Greetings,

Working on a 1920-something "Stodart" piano (brand name appears on the fallboard only--no where on the string frame).

The question at present is: What is the function of the "L" shaped piece that screws into the horizontal member of the wippen body? As can be seen in the (hopefully) attached image, the short, bent part of the "L" hovers above the rear of the repetition lever. There is a piece of felt on top of the repetition lever underneath the bent part of the screw, suggesting that there could be contact between the angled part of this screw and the top rear of the repetition lever. We have not been able to discern the function of this part, which I have not seen on any more modern grand actions. When we rotate the bent part of the "L" screw 90o, so that it is parallel, rather than perpendicular, to the repetition lever. the action still seems to work in every other respect.

Thanks,

Alan

In the book "Piano Parts and Their Functions", Merle H. Mason, it is shown on several pages but is only labeled on page 31, plate XIV, in the small Baldwin Grand drawing as #39.There it is called the "Repetition Lever Stop Hook". 

In the Japanese version of the book it is called the "double-action lever resistance hook". 

Could not find an explanation as to its function. 

Thanks for checking in with Mr. Mason, Geoff.

As I started to ruminate about this, my thoughts immediately turned to Kawai and all of the great research shared from their work with high-speed videography.

I strongly suspected that things were going on that could not be detected by the naked eye. Anyone who has. attended Scott Murphy's excellent class about his work with high-speed videography (or viewed his videos on the PTG website) knows just how revealing that way of looking at things can be.

Thanks, as always, Don, for the benefit of your considerable experience!