I believe I mentioned this in my regulating series in the Journal a couple of years ago. At least, I mention it in the regulating classes I have taught.
Anyway, the fundamental issue here is for us to mature from using specifications to using parameters. We inherit specifications from what factory workers are told to do to make the piano work so it can be shipped. A specification says "do this" and doesn't explain what the issues are. Parameters give us the "ditch on either side of the road" so we can then navigate as we see fit -- whether that is pulling out to pass another car or pulling over to the right to make way for an oncoming oversize load.
In the case of the key frame, I believe they should be set from scratch the way(s) we have been taught. But keyframes are all flexible and we can take advantage of that flex. Parameters tell us how far we can go before something bad happens. Specifically in this situation, the guides can't go so far down as to lift either the front rail (or perhaps the back rail) off the keybed. Conversely, they can't be so high as to knock (or simply just allow the balance rail to flex) when the key is played. (Perhaps, when the key is played when one or more pedals are being depressed.)
So, between those two parameters, nothing bad will happen. You CAN use the guides to make small changes in key travel.
Really.
Even if you have been told "never use the glide bolts to adjust key travel".
And you don't have to feel guilty about doing substandard work.
As our craft matures, we need to question dictums like that so that we understand the principles behind them. When we understand principles we will know the appropriate parameters and have greater freedom to provide service appropriate to the situation.
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Keith Akins
Akins Pianocraft
Menominee MI
715-775-0022
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Original Message:
Sent: 02-28-2018 19:22
From: Ryan Sowers
Subject: Adjusting Yamaha grand action glides
I recently had an interesting discussion with Greg Frank at Yamaha regarding the proper bedding of the balance rail. I'd like to do a poll of members here.
I remember being taught that the guides should not be used to achieve proper key dip. But, are there times when it is appropriate to turn the glides down to raise the key height, thus getting more dip and aftertouch?
I'm curious what folks on this list think. Would I be violating good regulation procedure if I used the action glides on a new C3 to get the proper key dip, or is it best practice to always adjust the glides so they don't affect key dip?
Thanks for helping with this question!
Ryan
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Ryan Sowers
Olympia WA
360-705-4160
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