Trap Work (Was: Disgruntled list members)

[Joel Rappaport]

This is getting long, so I am replying up here at the top.  Jon Page has
an excellent point (from another post entirely).

Warren, your idea is much better than a simple capstan mostly because of
the force and frequency of right (damper lift) pedal use.  However, now
that I think of it, we use a capstan to limit the sostenuto lever travel
and stay with the block of hammer felt for the damper lift pedal.  As
long as it stays glued onto the lever (we use hot hide glue), it won't
change much from compression and is a big enough surface to take a lot
of foot stomping (ever watch André Watts when he really gets into it?).

Also, Allan L. Gilreath made an excellent observation:
> However, I've found the
> capstan that Kawai uses (perhaps used to use?) can get the threads stripped
> out in the wood and not perform their function under HEAVY use.

The lag screw or bolt that needs grinding starts to be too much time
compared to using a felt block.  It only takes 1-2 minutes to cut an
appropriate piece of hammer felt and glue it onto the lever.  "Fine"
adjustments can be made by sliding the felt block just a little bit
forward or back on the lever just before gluing it as you set the amount
of damper lift you want.  The lever moves in an arc, you know, and
placement of the block will change how far up the dampers are allowed to
move.  This adjustment is made in conjunction with how high the keys of
a finish-regulated action raise the dampers.  Then the damper stop rail
is adjusted.  Hope this helps.
----Joel
>
> Joel Rappaport wrote:
> >
> > Greg Newell wrote:
> > >
> > > Joel Rappaport wrote:
> > > >
> > > > The excessive pedal and trapwork travel is what does it.  Additional
> > > > pieces of hard felt or a new, thicker block of hammer felt glued on top
> > > > of the trapwork lever will adjust this.
> > >
> > > What about retrofitting the style limiter that Kawai uses with the
> > > inverted capstan to limit pedal travel?  Seems like a good idea.
> > > Adjustable whenever!
> > >                                    Greg
> > >                                    gnewell@en.com
> > ------------------------
> > An excellent idea, Greg.  All you would need to do is install a capstan
> > on the underside of the keybed.  It should hit some pretty hard felt for
> > the regulation to be effective and long lasting.  The reason I did not
> > mention this (we do this in our rebuilding, BTW) is that the capstan
> > will give you a really good fine adjustment to the trapwork lever (and
> > hence, pedal) travel.  What Jim Coleman was referring to, however, was a
> > pretty severe case of heavy foot.  Considering the small area of the
> > capstan head and the force that is placed on the trapwork lever during
> > foot stomping, a 3cm (about 1-1/4") square of hard hammer felt will take
> > that force better.
> >
> > Joel
>
> Joel,
>
> What about using a  hex head lag screw or a large flat-headed machine
> bolt with the business end rounded off on the grinder to give you fine
> contol as well as a broad contact surface?
>
> What'cha think?
>
> Warren
> --
> Warren D. Fisher
> fish@communique.net
> Registered Piano Technician
> Piano Technicians Guild
> New Orleans Chapter 701