Hi Everyone.  Here is an easy way to provide quick hammer stroke
adjustment for upright pianos and players.

1.  Remove the felt or action cloth from the hammer rail and action
brackets.

2.  Remove the hammer rail

3.  At each place where the rail intersects with the action bracket,
drill a pilot hole in the rail large enough to thread a ordinary
capstan screw.

4.  Prepare the capstan screw by grinding the end flat, then gluing
a regulating button (jack letoff) punching on the flattened head of
the capstan.  Shellac or plastic glue works very well for this.

5.  If your hammer rail is cut at sharp angle, like many players are,
you may need to cut the threaded shank of the capstan screw shorter or
use a shorter capstan screw to prevent it from breaking through the
other side of the rail.  Be very careful that the pilot holes end up
square with the action bracket with the rail at rest, and will not
interfere with the operation of the player sub rails.

6.  Reinstall the rail on the action.  Hammer stroke can now be easily
adjusted at any time by adjusting the capstan screws.  The action
punchings will insure silent operation.  The adjustments will also
compensate for a slightly twisted rail.  As anyone who has encountered
one of these will tell you, it is not an easy job to shim up a twisted
hammer rail firmly at all four points.  The capstans also look far
better than various thickness of felt and paper shims.

Andy Taylor
Tempola Music Rolls