[pianotech] Rendering fix

[Jim Ialeggio]

I've service this 10yr old 
Hallet&Davisbostongermancraftsmanshipmadeinchina grand. Everytime I 
visit it, it turns on my cynicism genes.

Each visit the rendering is worse. Its now almost untuneable...I got it 
there this week, but am not inclined to repeat the performance.

House is wet in spring and summer, dead dry antique building winter. 
Sold a full DC/w undercover along with dire warnings.

So with the DC in place, they are prepared to let me mess with the 1" 
highly compressed felt behind the brass counterbearing. In theory, this 
should be a reasonably rendering piano, with reasonably short segments 
between agraffe/capo and brass half round counterbearing bars. The 
felt/string bottom  interface has obviously got the high friction 
corrosion look, though string corrosion on the visible surface is not 
unduly evident.

My plan is to try the tenor section first and see how it goes. CCW pin 
just enough to pull becket. Pull coils off most of the pins, maybe 
leaving the ends in place.  Remove felt, which I bet is glued helpfully 
in place. Reduce felt height to just contacting string, reduce felt 
width to 1/4", run Scotch Brite on underside of strings to lessen 
existing corrosion.

Questions:

1-Does this procedure have a prayer of success, or will current 
underside corrosion as evidenced by the rendering issue, thwart the effort?

2- As natural felt with its moisture wicking trick, in my opinion, is 
the absolutely worst material one could come up with for a bare metal 
under-string interface, has anyone tried dousing the felt with something 
like Profelt to both lubricate it, but more importantly kill its 
moisture-wicking tendency?  I'm familiar with the CLP trick for 
lubicating the felted string segment, but I'm referring more to making 
the felt less able to attract and hold ambient moisture. (by the way, 
while I use the CLP trick, I find it mostly ineffective with this kind 
of rendering problem).

Jim Ialeggio

  --
Jim Ialeggio	
jim at grandpianosolutions.com
978 425-9026
Shirley Center, MA