heavy action..

[Stan Kroeker]

>..Dear List:
>
>..i have in my posession a DH Baldwin action..customer is correct when she
>says the action is *heavy*..bass section feels like there's concrete on the
>back of the keys..tenor and treble section feels fine..i backed the jack off
>of A0 till it missed and then reset it..still feels heavy..
>
>..suggestions warmly welcomed..

When presented with a piano which exhibits an excessively heavy touch as
you describe I prefer to start with the basics.  Heavy, unresponsive touch?
Suspect excess friction...somewhere.  Several years back there were some
timely articles in the Journal concerning the evaluation of friction and
weight in the action.  With a simple set of accurately calibrated gram
weights, you may measure downweight and upweight on selected keys (without
the weight of the dampers).

Subtract upweight from downweight and divide by 2 to determine frictional
resistance (12 - 15 grams should be ok).  Add upweight and downweight and
divide by 2 to determine weight resistance (35 - 40 grams should be ok).
These basic measurements will quickly determine whether the action is
suffering from excess friction, weight or both.  David Stanwood (may we
call him the touch weight guru?) has taken this analysis a quantum leap
forward with his new touch weight metrology but I'll leave that discussion
for him or someone else more qualified than I to continue.

You may choose to assume that there may be excess friction in this action
and simply proceed from the front of the key to the top of the action to
examine all the friction points and ease and/or lubricate where necessary.
Protek works on keypins, capstans, jack tips and repetition levers;
micro-teflon powder works very well on whippen cushions and knuckles (even
keybushings if you want to be fussy).  Remember to check the balance hole
on the keys for proper fit and ease if necessary with the tapered tool
inserted through the key button.  Of course, tight action centers
(particularly the hammer shank flange centers) are another common cause of
excess friction and may either be treated with Protek or repinned where
appropriate.

If there is excess weight in the action, particularly the bass section, you
may choose to remove some mass from the hammer moldings (by tapering the
sides of the hammer).  As there is roughly a 5 to 1 ratio from the tip of
the key to the tip of the hammer, removing 1 gram of weight from the hammer
molding results in a 5 gram reduction in the down and upweight measurements
at the playing end of the key.

Hope this helps,


Stan Kroeker
Registered Piano Technician

Kroeker & Sons Piano Experts
59 Quiring Bay
Winnipeg, Manitoba
Canada  R2G 1Y5

Ph.   204-669-5881
Res.  204-661-5621