regulation problems in Aeolian era M and H 50"

[Michael Spalding]

---------------------- multipart/alternative attachment
Dave,

I would take the opposite approach to the typical "sticky key" troubleshooting scenario:  in that case, you start at the key and work towards the hammer, and in this case, I would start at the hammer and work back towards the key.  Hammer travels smoothly up and back?  fine, now look at the dampers, by themselves, then on the pedal.  Plenty of travel?  No hangups?  Now lift the wip, and see how damper lift times with the hammer, see if you can get significantly beyond letoff before running into big resistance.  etc.

One other thought:  Does this Mason have the cheezy Aeolian sostenuto?  The one with pointy wires protruding from the bottom of the damper levers, and a flexible rubber "blade"?  Make sure the damper levers are not running into the sos blade during normal play.  

lotsa luck

Mike


----- Original Message ----- 
From: 
To: pianotech@ptg.org
Sent: 12/18/2004 2:34:45 PM 
Subject: regulation problems in Aeolian era M and H 50"


Salutations, 

I've got some regulation problems on a 50 inch Mason upright from the 70s.  I've worked on other Aeolian uprights of that vintage, and some of them have the same problem.   

The initial problem was that the keys weren't bottoming out on punchings.  It seems that it's been that way since new(though they bought it used).  There was a huge gap between the bottom of the key and the punching when the key was depressed.  This led to hammers blocking, bobbling, and a feel that could only be described as spongy.   

At my last visit, I added punchings, and improved the feel somewhat, but some of the bobbling is still there.  I also had to increase letoff distance in some areas of the keyboard an unacceptable amount to get it to work without hammers blocking against strings. 

I think that the main problem is that the key height is too great.  It was somewhere around 70mm, though I forgot to write it down.  More precise measurements are necessary, and they will be forthcoming after my next visit there in January.  Blow distance is at 1 7/8(the only thing in the piano that seems at spec...:-), but it doesn't seem to be enough. 

I tried lowering the key height on a few sample keys by removing balance rail punchings, but there was nowhere near enough aftertouch.  Should I try increasing blow distance to 2 inches or more?  Any ideas???  Haaalp??   

Any input is welcome, 

Dave Stahl 
---------------------- multipart/alternative attachment
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/c2/aa/c1/34/attachment.htm

---------------------- multipart/alternative attachment--