Very interesting! Just another example of how things are always more complicated than we first think!
I found the contrast between the first paragraph and the last paragraph somewhat ironic, though.
In theory, the underlever spoon should pick up on the key end felt so that
half way through the travel of the underlever spoon, the spoon pickup
point, the balance point of the key and the under lever center should fall
on a straight line.
This method is more elaborate, and somewhat more difficult. However, when
the job is done, at least in theory, it should be better.
Then at the end there is a big caveat:
Caution!
This method, while controlling the relationship between the key and
underlever, can put the damper action either too low or high to work
properly. Before adopting the half stroke method for locating your
damper action, be sure that that the damper system works in all aspects.
I'm assuming this has to do with the concept of the rotating friction as opposed to sliding friction with the spoon/key end felt relationship. We've seen underlevers that have dug trenches into key end felt, and the idea of reducing friction makes sense. But in the end it has to work! So much in piano work is compromise.
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Ryan Sowers RPT
Olympia WA
(360) 480-5648
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Original Message:
Sent: 07-12-2024 12:56
From: Lyle Hiorns
Subject: What is this tool?
Hello Ryan and Tim,
Sorry for the incorrect link. Attached is how the jig is utilized.
WNG has all their PDF instructions in their FAQ page, here. This attached PDF is under Damper Action (Assembled) Installation.
Original Message:
Sent: 07-12-2024 12:43
From: Lyle Hiorns
Subject: What is this tool?
Hi Tim,
That is WNG's Damper Pickup Half Stroke Gauge, which is part of the installation tool kit. In the link you provided above (Damper Action Installation Tool Kit) click on Product Info. This gauge is at the bottom of the list without a picture.