[CAUT] Down Weight Too High With New Hammers

[Andrew Anderson]

Or, the demand for miracles never ceases... ;-)
Andrew Anderson
On Aug 25, 2010, at 11:14 AM, Paul Milesi, RPT wrote:

> Thanks much for these discussions.  I will be making best efforts to  
> obtain useful data, and now have a better idea of what might be  
> needed.  FWIW, I did sample dip on several keys in different  
> registers, because I wasn’t getting much, or any, aftertouch with  
> the hammer line and let-off I’d set.  The dip was (and still is)  
> roughly 9-9.5mm throughout, or less than .375”.  I am catching on  
> now that, assuming the piano was playing well when set up with this  
> dip with original hammers, that likely means a relatively high  
> action ratio?  Obviously I haven’t set dip yet with the new hammers,  
> only roughed things in to make sure everything works in relation to  
> others as they’re supposed to.
>
> Again, the piano was so beat up, played so hard (gospel church music  
> all week), that things were pretty tattered.  Compound that with,  
> one year ago, my having to literally just screw the new hammers on  
> the rail one morning, align jacks quickly, and set let-off just to  
> get the piano to play somewhat for an important event for the  
> university’s new president.  I mean, it barely played.  But I tuned  
> it and they used it in a big ceremony.  That was the beginning of  
> the resurrection, and it was another year before I could get the  
> piano moved to a space where I could really work on it.  The point  
> of all this is, to give you a sense of why I don’t have a lot of  
> carefully gathered specs, etc., and have not exactly worked  
> methodically.  Just realities.  The work started on an emergency  
> basis, and we’ve gone from there to wanting to make this a recital  
> piano.  Miracles never cease....
> -- 
> Paul Milesi
> Registered Piano Technician (RPT)
> (202) 667-3136
> (202) 246-3136 Cell
> E-mail:  paul at pmpiano.com
> Website:  http://www.pmpiano.com
>
>
>
> From: David Love <davidlovepianos at comcast.net>
> Reply-To: <caut at ptg.org>
> Date: Wed, 25 Aug 2010 07:40:52 -0700
> To: <caut at ptg.org>
> Subject: Re: [CAUT] Down Weight Too High With New Hammers
>
> Until we have more info from Paul it’s difficult to know what to  
> suggest.  The original is probably 16 mm and Paul has changed to  
> 17mm on the knuckle.  That will increase the dip specs but .415 is a  
> fairly deep dip and would suggest an action ratio that is on the  
> lower side already (assuming that measurement is accurate).  So  
> unless the hammers are really monsters (which they could be) then I  
> would expect one to be able to achieve a reasonable FW even if it is  
> with a moderately higher BW.  A direct measurement of the action  
> ratio (6 mm dip causes hammer travel of x?) would be helpful.  As  
> was mentioned by several contributors, friction readings need not be  
> a mystery and can easily be ascertained by a survey of the UW and DW  
> through the keyboard.   Remaking the keys certainly would solve any  
> questions and problems but it’s not in the cards for this job.   
> Still, having redone many of these actions without remaking keys  
> there are always solutions.  But without the data it’s difficult to  
> know the limits of what is achievable and the best way to get there.
>
> David Love
> www.davidlovepianos.com
>
>
> From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf  
> Of Brent Fischer
> Sent: Wednesday, August 25, 2010 6:58 AM
> To: caut at ptg.org
> Subject: Re: [CAUT] Down Weight Too High With New Hammers
>
>
>
>
>   Hey guys,
>
>      David, I know it is counter-productive to increase
>   interia by moving leads to the front. We know Steinway
>   fit the action to the strike line therefore moving the
>   capstans away from the theoretically correct position.
>   Hamburg fits the piano to the action which is why
>   I've seen so many prefer it over NY. I am interested
>   in your solution given Paul's constraints. I believe
>   the original knuckle dimension is around 15.5 mm?
>   I found this always increased dip when going longer
>   however am not an action designer, but have had Roseland
>   Piano re-manufacture several of this vintage keyboards
>   with corrected ratios and it was the answer to being
>   able to lead closer to the balance rail with great results.
>
>
>

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