Hi all,  almost two years ago I asked for advice restoring a Hupfeld.
A few MMD readers have helped a great deal.  Last week I finished
restoring the stack, and the pedal assembly is also back in working
order after much error-hunting.

Now everything is in working order I went to put the mechanism back
in the piano (the piano isn't mine but a friend's).  After some more
error hunting, finding and fixing everything works (though I need to
find and fix some general leakage).

The problem I need some advice with is the following: there are four
notes somewhere in the middle of the keyboard (F to G#), which all play
if one of their holes in the trackerbar is uncovered.  How is this
possible?  The only logical explanation to me seems that there's
something wrong with the gaskets.

This could be the gasket behind the trackerbar (it's a 73- and 88-note
player so the trackerbar is turnable to switch from 73 to 88 and back)
or one of the gaskets on the junction blocks connecting the head to the
stack, one above the keyboard, one below.  People familiar with the
early Hupfeld mechanisms will know what I mean.

The gasket connecting the stack to the junction block is renewed, the
other two seemed fine.  I wonder where the problem could be...  Most
likely in the trackerbar gasket, I think, but if anybody has any tips
or other clues about the problem, please let me know.

Regards,
Niels Berkers
the (today sunny) Netherlands