Spurlock Damper Design (larger dampers in bass for old upright)

[Farrell]

Sounds like we are refining things here. Thanks for all the tips. They sound
good.

> Is the piano in your shop? It's a lot easier to solve the little problems
> with the piano there.

You don't know how many times I wished the piano was in my shop. No, it is
not. It is about 25 miles away. Oh, well. I guess that just means at least
one or two trips out there for fitting, etc. I'm sure if I had done 87 of
these jobs before, I could do all in one quick trip. But I have not, this is
upright damper job #1. So I will go there as many time as is necessary to do
the job right!

Thanks again for your input. This is great.

Terry Farrell

----- Original Message -----
From: "Ed Sutton" <ed440@mindspring.com>
To: <pianotech@ptg.org>
Sent: Friday, August 31, 2001 10:25 AM
Subject: Re:Spurlock Damper Design (larger dampers in bass for old upright)


> Terry-
>
> No, step one is: Make a sample damper and see if it works.  This is how
you
> find the answers to the other questions.  Step two will probably be: Make
> another sample damper, etc.
>
> The dimensions Bill gives in the article are a good place to start.
> 1/8 inch boards seem a little thick. Seems to me I found something a
little
> thinner.  Someone mentioned (model) aircraft plywood- that would be very
> good, and can be found in 1/16 inch thickness.
>
> I used Schaff #947 Grand damper lifter felt.  It's 2mm thick. I liked it
> better when it was blue, but now they are selling brown. O well.
> Temperament strips would be too thick and soft, I think.
>
> When you do it, you will see the problem of clearing the damper wires when
> the damper lifts off the string. If the piano originally had very small
> dampers, the lower end of the long damper will tend to bump into
neighboring
> damper wires.  On pianos designed with long dampers, the wire is bent in a
> dogleg to clear the neighboring dampers.
>
> Keeping the damper as thin as possible front to back will help, so will
> getting it as close to the hammer as possible.  Finally you may find that
a
> slight change of dimension, and possibly trimming the ends at angles will
> get larger dampers on the piano without having to rebend or replace the
> damper wires.
>
> But all of this is easier to see in the piano than to describe in words.
> Therefore, make that sample damper, try it, refine it, etc.
>
> Is the piano in your shop? It's a lot easier to solve the little problems
> with the piano there.
>
> Have fun! It's a satisfying job to do. You'll feel high class about it!
>
> Ed S.
>
> ----------
> >From: owner-pianotech-digest@ptg.org (pianotech-digest)
> >To: pianotech-digest@ptg.org
> >Subject: pianotech-digest V2001 #1115
> >Date: Fri, Aug 31, 2001, 7:00 AM
> >
>
> > -----------------------------
> >
> > Date: Fri, 31 Aug 2001 07:45:03 -0400
> > From: "Farrell" <mfarrel2@tampabay.rr.com>
> > Subject: Re: Spurlock Damper Design
> >
> > I have been contemplating the sequence of procedures I would use to
> > construct a set of dampers and the best I can come up with is as
follows:
> >
> > 1)  Cut appropriate number of 1/8" thick X 3/8" X 2-1/4" (or whatever
length
> > you decide) damper boards.
> >
> > 2)  Cut 3/8" wide felt damper wedges, etc. into 5/8" lengths (or
whatever
> > length you decide).
> >
> > 3)  Glue felt to board, being real careful with felt piece alignment
> > (perhaps best to use a jig for training).
> >
> > 4)  Line up dampers side-to-side, felt side down, and glue 1/8" thick
spring
> > rail felt to back of dampers boards.
> >
> > Is spring rail felt the best to use (that is what Bill Spurlock uses)?
What
> > about muting strips - they are available in various thicknesses -
perhaps an
> > advantage to get best fit? What about understring felt - or is that too
> > firm? What about action cloth - again, available in various thicknesses?
Or
> > any other felt work best? Any thoughts? Thanks.
> >
> > Terry Farrell