overcentering justified?

[Bob Hull]

---------------------- multipart/alternative attachment
The tail arcing was done with the Spurlock jig.  Only the shank/flanges and hammers have been changed.  So, yes drop is changed. Balancier is same. They had a drop of maybe 3/8 below letoff on the old and I'm doing more like 1/16 below let off for drop.  The old let off is about 1/32 in mid range.     I believe backchecks are leaning slightly away at rest, I'll have to look again Monday when I'm back at the piano.  
 
If the jack is not resetting under the knuckle during fast repetition, is the knuckle being sent flying up again from contact with the top of the rep. lever ?  I decided bouncing was not a good word since it implies that one or  both of the parts are being set into motion through a compression and release of energy from their surface.  I'm sure the knuckle surface compacts or compresses but not in the same sense as a basketball.  
  Bob Hull

A440A@aol.com wrote:
I wrote:
<< >Repetition speed is usually more dependant on checking distance than 
>anything else. How far away from the string are these new hammers >checking? 

Bob sez:
>>I set the checking distance of the new long bored distance hammer at the 
same height as the old hammer and the new did not repeat anything like the old.
During very fast repetition, does the hammer tail come into contact with 
the backcheck even if the checking distance is set as high as possible (but 
not so high that it drags on the way up), or isn' t the knuckle bouncing off of 
the top of the jack? <<

Are the tails shaped on a 2.5" radius? and are the back-checks leaning 
slightly away from the tail at rest? 
As far as knuckles bouncing off the top of the jack, the jack has to be 
under it to do that, so the knuckle will to either need to lose contact with 
the jack on the way up, or the jack must find time to reset. 
Was the only thing changed in this action the hammers? No changes to drop, 
spring or balancier? 

Ed Foote RPT 
www.uk-piano.org/edfoote/
www.uk-piano.org/edfoote/well_tempered_piano.html

MP3.com: Six Degrees of Tonality
_______________________________________________
pianotech list info: https://www.moypiano.com/resources/#archives


---------------------------------
Do you Yahoo!?
Yahoo! SiteBuilder - Free, easy-to-use web site design software
---------------------- multipart/alternative attachment
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/5f/c8/90/6d/attachment.htm

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