John Tuttle obviously didn't understand my suggestion in regulating the
Pratt-Reed, and after rereading it, neither did I. So let me rephrase
it a little:

   Everything about a piano or a player piano begins at the key. By
that, I mean the performance of the piano action and its regulation.
The player can only play as well as the action will allow. When someone
who is unfamiliar with action regulation and yet who has a problem with
player regulation tells me they have a problem with blocking and
bobbling hammers when the player plays the piano, they are telling me
that the regulation is "all over the place." When they say that "it
plays fine by hand" they are telling me that they felt there was no
need to regulate the action before sticking in the player. Either they
tell me that the piano action is correctly regulated, first, or I will
advise them to do that, since a pianist can compensate for all kinds of
problems at the keyboard and poor regulation won't show up.

   Once you have properly regulated the piano action, from the key dip
through to the hammer, only then will you be ready for a decent
performance with the player. Too often, regulators will give the key
more dip than it's called for when they have bobbling notes, rather
than going to the source of the problem.  That is not going to prevent
his player from bobbling notes, even after he regulates everything
else!

   So I repeat-- begin at the key. Everything regarding the action of
the piano begins there. And if you cannot get the piano action to work
well after the key dip is correct, then go after the real culprit. It
could be a number of things. What you are talking abut here is a
sort-of trapeze act in which everything has to be at the right place,
at the precise time.

   I also do not recommend changing the design of the player, like
adding things that are unnecessary, to "work around" the problem. The
quick fix John Tuttle describes will not, in a thousand years, solve
the problem of bobbling notes, although it might help the ones which
block their strings. Still, you cannot "regulate" it that way. So I
would encourage Mr. Toto to "do it right the first time." Why spend all
that energy, and when you're done, you still need a complete
regulation?

   Each player action has at least one overall adjustment, and
individual note adjustments with which to regulate it to the piano. Use
them. And if the regulating button stems want to break, heat them up
first with a micro-torch or soldering iron-- not so that you are
burning the wood, but that will break the rust freeze and let you
adjust it.

Craig B.