Hi Jason,
Interesting set of questions. I can't say I have specific answers, but a few observations. The birds-eye is there to maintain spacing within small confines, and to reduce friction. Quality pianos of the mid 19th century tended to have some form of brass flange that captured the pivot pin, whether individual or a long pin on which 6 - 12 hammers were strung. The brass was a smaller profile than wood, so there was less surface for friction, hence no particular need for some sort of spacing design. Though the later Billings flanges do have a profile that minimizes contact near the pin.
Even as early as mid 19th century, power tools were common in factories, though of a different design. Typically there would be a central steam engine, which would drive a series of rotating shafts, connected by belts. Such rotating shafts would occur in any room of the factory (often of multiple stories) where power was needed. Individual tools (like drill presses or saws) would be connected or disconnected to the shaft, again by belts. I am not familiar with the smaller details of precisely what sort of "clutch" or the equivalent would have been used, but power machinery was used pretty universally. Much of the precision had more to do with the skill of the operator, as opposed to modern CAD driven machines, but precise drilling could be done by means of precise jigs.
As to the birds-eye shape, and ability to machine it, I really don't know. Seems like it would take some sophisticated method to create the right cutting tool, and I don't know when such tools could be made fairly easily. I also don't know when birds-eyes first became common. Certainly fairly early in the 20th century. My memory seems to have parts from 1860s - 80s that were straight, without the birds-eye, but I don't have instruments available to check that somewhat vague impression.
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Fred Sturm
University of New Mexico
fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein
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Original Message:
Sent: 01-30-2013 22:04
From: Jason Leininger
Subject: Birdseye
I was wondering if anyone knows when the Birdseye came into common use in action centers? What shortcomings of previous designs did it address if any? Also how were action centers drilled accurately, very early on, say before the use of the modern drill press, and what tool or bit was/is, used to make the Birdseye? It seems that possibly watchmakers tools could have been useful early on, along with complex molding planes for the profiles of other action parts. Any input?
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Jason Leininger
Las Vegas NM
412-874-6992
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