Clicking notes on a B

[Will Truitt]

If you have time, remove and reglue as you indicate.  If you need a quick
and dirty repair in a hurry (as you might in the minutes before a concert),
tilt the hammer up and apply a few drops of thin CA glue to the shank end.
It will wick out the glue joint and reglue the hammer.  

Will Truitt

-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Andrew Anderson
Sent: Tuesday, October 07, 2008 11:06 AM
To: Pianotech List
Subject: Clicking notes on a B

We had the Long sisters Duo (great artists, don't miss them if you  
have the opportunity) here at TAMIU.  During the course of their  
practice and the pre-concert tuning (done minutes before) some  
clicking developed in the hammers.  I held adjacent notes down tight  
to eliminate slapping of the front rail.  No joy.  I put a finger over  
the damper and softened the upstop.  That did seem to make a little  
difference.  I checked, the rail is in place with plenty of felt  
apparent.

I've had to reglue a few dampers including one after their practice so  
I'm suspecting the hammer-shank glue joint.  Would this be a candidate  
for a little vinegar to reactivate the glue and tighten the joint?  Or  
would it be preferable to simply remove the worst hammers, knurl the  
shank and re-glue?

Andrew Anderson


On Oct 6, 2008, at 2:30 PM, Richard Brekne wrote:

> Greetings:
>
>
>   It's only logical that weight and distance ratios are related.  You
>   can't change the weight ratio without creating the need to alter
>   regulation specs. While problem actions we're talking about that
>   have excess lead have, by definition, a mismatch between ratio and
>   hammer or strike weights, they also generally regulate with too
>   shallow key dip (<10 mm), at least by modern standards.  Changing
>   the capstan or knuckle position to improve the ratio to strike
>   weight relationship will entail increasing the dip but that's
>   usually a good thing, or at least a perfectly acceptable thing.  If
>   you want the action to regulate by older standards with shallower
>   key dip you will need to use very light hammers to go with a higher
>   action ratio (or compromise the blow distance).
>
>   One thing that would be nice would be to establish the relationship
>   between the Stanwood weight ratio and the distance ratio (since they
>   don't currently match) so that regulation specs could be targeted
>   using weight ratio as the standard.  However, since both numbers are
>   easy to calculate it doesn't present that much of a problem.
> I'm not sure all this is all that accurate. One has to remember that  
> Stanwoods weight ratio is all in all an entirely different puppy  
> then the distance ratio as given by for example Ron Overs on his  
> website. Stanwood does two things that are not really compatible  
> with the distance ratio and can explain why the SWR can be the same  
> for two actions of different distance ratio.  Number one, he throws  
> out the individual ratios of the top two levers in the action and  
> combines them into one quantity. Then this quantity is never really  
> used directly in his formula but is rather factored out to arrive at  
> his equation of balance ratio. (see my article on dissecting his  
> equation from a couple three years back in the Journal)  Secondly...  
> his equation is that of the ratio of  the SW to that of the combined  
> weight of BW + FW - WW where WW is the whippens radius weight times  
> the key ratio. It is not a direct ratio such as the distance ratio  
> which is the ratio of hammer movement to that of the key movement.
>
> It is clear that one can achieve identical distance ratios for the  
> upper two arms using various combinations of the individual arms.  
> Choice of individual arm lengths affects the speed of each of the  
> parts in each individual arm and the speed of the individual arms  
> themselves. This illustrates part of the difficulty in attempting a  
> translation from one type of ratio to the other. The end balance  
> weight ratio... or SW ratio as Stanwood has termed it is not  
> porportional to either a standard distance ratio or any given speed  
> ratio.
>
> The only relationship that does exist without further ado is that if  
> one increases or decreases any given action ratio through some or  
> another manipulation, one will indeed alter all other action ratio  
> measurements in the same direction. That is to say if you increase  
> the SW ratio, then you will increase the distance ratio and the  
> speed ratio as well.  How much in each case is a bit more complicated.
>
> Another thing,... a change in the SW ratio by no means necessarily  
> implies a significant change in action regulation specs. One can  
> alter the SW ratio quite a bit and end up requiring no more then a  
> couple mm change in blow distance to achieve same aftertouch for  
> same key dip and same letoff/drop.
>
> Cheers
> RicB
>