How would a pin block that is binding on the action rail cause tuning instability?
When the action cavity is too low, I've used a belt sander to raise its height. Did something spill on the area to cause swelling?
Is this the original block?
Measure string height and HCH, the cleats may be too high. The difference between HCH and WCH should be 64 mm.
B's are notorious for poor geometry.
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Regards,
Jon Page
mailto:
jonpage@comcast.nethttp://www.pianocapecod.com------------------------------
Original Message:
Sent: 08-21-2022 21:25
From: David Love
Subject: Bowed pinblock
If the dome shaped flange screws are a problem you can replace them with flat topped screws. I've done this recently.
What makes you think the pin block is bowed? Sometimes replacement #pinblocks are not properly shaped and they can be too thick in the middle pushing them below the stretcher but even then I'm not sure why that would cause tuning instability. I'd look for other reasons.
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David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
Original Message:
Sent: 08-21-2022 17:36
From: Timothy Michaels
Subject: Bowed pinblock
I have a recording studio piano with a bowed pinblock. Most of the time it can get through a multi day session okay, but every once in a while it will go out enough to make me come back the same day. I tune it at least a couple times a week for the past two years for sessions. They have been wanting to replace it for years because of many other issues with the piano, but moving at a glacial pace. It's a Steinway B, 1908. Was wondering if some sort of repair other than replacing the block could be done.
The bowed section is worse in the 5th octave. The hammer flange screws would get caught on the block in that section and I had to grind down the screws a bit for clearance. That is where the tuning is most unstable.
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Tim Michaels
pianotechtim@gmail.com
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