Importance of the staple: was hammer felt (Renner Blues)

[David Andersen]

>yesterday I experimented on shot Steinway hammers I was about to replace (on
>a D) and , using a single long needle (8 mm) I tried to find hard spots in
>the zone of felt above the staple & under the shoulders but nearer the
>molding than usually. It was amazing that the hammers became very fast
>totally playable and round and pleasing (these where 'old style Steinway
>Hamburg hammers')

This has become crucial in my voicing protocol, thanks to Dale Erwin.  
Hard spots, or "knots" on the shoulders can be miraculously softened, and 
the tone radically improved, by just a few deep 
(8-10mm) and precise single needle strokes wherever the "knots" occur 
between 9:30 and 11:30.
I angle the tip of the needle back toward me the higher I go on the 
shoulder.

So far, this works like a charm, is very controllable, and has been 
tonally pleasing every time.
Seems to work on hammers both pre-voiced and not (new pianos, direct from 
factory.)

Best......David A.