dampers

[Barrie Heaton]

>I have been tuning one Robertson overdamper piano for about a
>year now.  That is the only one I know of in playable shape in
>my area.  I have seen two others that were in need of total
>restoration to be playable. But, I got a call recently about
>another overdamper piano that I may be tuning soon if
>it is in good shape.  For me it is NOT routine to tune this
>piano!  Probably because of lack of experience with them.  I
>would appreciate any hints you can give me on how to tune this
>type of piano more efficiently.  Also, do you have any
>information about regulating the dampers on these pianos?
>Another technician replaced all of the damper felts on the
>action

>David A. Vanderhoofven
>Joplin, MO
>Associate Member, Kansas City Chapter PTG
>davander@aol.com

Sorry for the late reply to this posting I have been on holiday
and I am weeding my way through the threds

1st to the regulating of the Dampers.
I am assuming the technician used end grain damper felt? if not
your in for some fun.  has the Robertson piano got a center
action bolt located on the top of the damper rail?
if not fitting one may solve your problem I will assume you have
not seen one an describe one. Think of a peace of wood in the
shape of  Golden Gate Bridge in the USA. make it approximate 4"
long 2" high .5" thick. looking at the side of the bridge Drill
a hole at the side of the block  of wood, to the top of the arch
to take a size 8 screw then drill two holes through the top   of
the block of wood  at each end.   Old action hammer screw will
do.   This is so you can attach the block of wood to the damper
rail,  place a 3"x 8 screw in the hole and line up to a good spot
between the Wrest pins and the Pressure bar and between two notes
mark and pilot the  3 holes for there respected screws.  Two on
the damper rail and one in the wrest planck when finished
tighten the 3" x 8  screw into the wrest planck and this will
pull the dampers in and help to reduce ringing off. if the piano
is a O/O set the block at the base break if a V/S find the best
place so it is not in the way when tuning.

To regulate take all dampers off keeping them in order use a long
muting strip and mute off all strings that the dampers will come
in to contact with start in the Bass replace one damper at a time
removing the mute for that note. crank the damper to space them
to the strings   it is important that the dampers have been
recenterd correct as it is only gravity that makes them work each
damper should be picked up by the bottom section,  1/3 of the key
dip this will give the action a nice touch. When played into
check the damper should have a small bit of play between the
damper body and slap rail, just like on a grand to much and the
damper kicks back, to little and the hammer will not check. hope
this will help

Tuning:
 use a paps wedge or stick wedge  some times I use a T hammer on
some pianos if there is v.little space between the wrestpins and
damper rail