Damp Action Drying

[Delwin D Fandrich]

Paul McCloud wrote:
> 
> ...Mark Burgett (Pianodisc) told
> me that he had a problem with Young Chang actions which would seize up
> after being played with the pianodisc.  He said that the pins would get
> heated up and the fibers of the bushing cloth would glue themselves to
> the centerpins.  It seems that the felt Young Chang uses is made in
> their own factory, and that there is some kind of residue left after
> manufacture which causes the problem.  He thought that since the
> Pianodisc is played sometimes for long periods that it shows up more
> often than with ordinary playing.  He may be right about it, though I
> don't really know.  But it does give one thought in regard to sticky
> action centers.
>   Thanks again for your input.
> 
> Paul McCloud, RPT
> San Diego, CA

-------------------------------------------------------

Paul,

We've had the same problem with Renner parts. We "play-in" each piano
before delivery using a machine that plays each key two times per second
for several hours. The fingers are set up to simulate the force of a
medium blow by a pianists fingers. 

We've attributed this "freezing-up" problem to the graphite coating that
Renner uses on their bushing felt, but it could just as easily be the
glue coming through. It's a litter hard to believe that the action
centers could get that hot, though. 

In any case, this is a different problem than the one your having with
damp actions.

My reason for building the box was so that I could slowly dry out the
entire action, not just spots of it as I had been doing with a heat gun.
I also found the heat gun to be often ineffective. Drying too fast,
i.e., using too much heat, would overly shrink the action centers
leaving me with much more work than I wanted to put into most of these
pianos. Slowing the drying rate freed up the action nicely without
causing a lot of peripheral damage. I usually did have to tighten every
single screw in the entire action, however.