Dampp Chaser and Grand Action

[Farrell]

David: How about a little background on this one? It sounds interesting to follow. You indicate that you have monitored the indoor environment for a year - what data do you have available - what have the humidity swings been? What area of the country are you in? Is the new home air conditioned? What kind of heat? Does the home have a humidifier? Might it have whole house humidity control (not bloody likely, I suppose). 

Have you been able to document touchweight during dry conditions, and then touchweight during high humidity conditions?

Thanks.

Terry Farrell
  
----- Original Message ----- 
From: "David Love" <davidlovepianos@earthlink.net>
To: "Pianotech" <pianotech@ptg.org>
Sent: Wednesday, August 27, 2003 12:31 PM
Subject: Re: Dampp Chaser and Grand Action


> This sounds like the most reasonable suggestion which I will try.  The
> piano is a new NY S&S B.  The piano, when moved from the showroom (air
> conditioned) to its new residence (high humidity at present, but showing a
> wide range of fluctuation on the hygrometer over the past year), became
> quite stiff.  Sample measurements of up and down weight show friction
> readings ranging as high as 20 grams on some notes.  Most of the problems
> on the measured notes seem to be in the hammer flanges.  Jacks are also
> sticking and a precise adjustment of the repetition spring is impossible
> with these types of humidity swings.  At present, as you can imagine, the
> piano also has repetition problems.  While treating all the flanges is an
> option and may be necesssary, if only to provide even resistance, I prefer
> to try and stabilize the humidity and create some kind of baseline before
> doing that.   While I understand the downside potential of putting a heater
> bar in the action cavity, it seems that the problems reported have occurred
> mostly with high wattage bars without humidistat control.  If we set too
> much downbearing and the piano sounded like crap, you wouldn't choose to
> avoid using any downbearing in the future.  Many of the things we do
> operate on the edge of disaster if not regulated properly.  That doesn't
> mean we shouldn't do them.  It's unfortunate that there isn't more research
> on regulating humidity within the action cavity itself.  Perhaps the
> manufacturer will see fit to conduct that kind of research.  It's beyond me
> to do it at the present time.  However, it's certainly an important area to
> control.  Since this seems to be an area of uncertaintly, I will opt for
> the under-the-keybed position and hope for the best.  
> 
> BTW for you touchweight enthusiasts, FWs = 85% max on average with BWs
> between 45 and 50 grams.  Add a little high friction and DWs were near 70
> grams on some notes.  Nice....  
> 
> David Love
> davidlovepianos@earthlink.net
> 
> 
> > [Original Message]
> > From: Tony Caught <caute@bigpond.com.au>
> > To: Pianotech <pianotech@ptg.org>
> > Date: 8/27/2003 11:32:09 PM
> > Subject: Re: Dampp Chaser and Grand Action
> >
> > Thank you Robin,
> >
> > I was about to suggest the same about fitting a rod under the keyboard, I
> > have done the same in Darwin Australia and have never had further problems
> > with sticky actions.
> >
> > Some one once said that you don't fit Dampp-Chasers to fix sticky actions,
> > only to keep the pitch constant but believe me, the customers just want to
> > play their pianos knowing that the piano is out of tune a little (or a
> lot)
> > is natural in this humid weather.
> >
> > It Works
> >
> > Tony Caught
> > Adelaide Australia
> > caute@bigpond.com.au
> >
> > ----- Original Message -----
> > From: <DCrpt@comcast.net>
> > To: <davidlovepianos@earthlink.net>; "Pianotech" <pianotech@ptg.org>
> > Sent: Wednesday, August 27, 2003 10:04 AM
> > Subject: Re: Dampp Chaser and Grand Action
> >
> >
> > >       I was trained in Dampp Chaser installation by Wendall Eaton.(Well
> > known
> > > consultant and Dampp Chaser distributer back in the 80's).He taught me
> to
> > cure
> > > sluggish keys and action centers in a grand by mounting a 7-F (15
> watt)on
> > the
> > > underside of the keybed just in front of the top of the pedal lyre and
> of
> > > course connected to a humidistat.I have done this on many
> > installations(most
> > > all with complete systems)and have not seen any problems in over twenty
> > > years.The principle of heat rising through the key bed helps keep the
> keys
> > and
> > > action dry with out heating the pinblock.I have found it also stabilizes
> > > Stienway key frames so the glides stay regulated.
> > >        I will add that it is an absolute no no to put a rod of any
> wattage
> > > inside the action cavity.                          Robin Olson  RPT 
> Wash
> > DC
> > >         P.S. for some reason my e-mail server does not include my return
> > > adress on replies to the ptg list.Sorry if that bothers any of you.
> >
> >
> > _______________________________________________
> > pianotech list info: https://www.moypiano.com/resources/#archives
> 
> 
> 
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