[pianotech] Pumper Flap Valve Leather

[Euphonious Thumpe]

Though this will make the "traditionalists" squirm, I can not but help believe that SOME modern material would be better for bellows flap valves 
( like nylon webbing with an air-tight facing? ) for this very reason. And also for longevity and uniformity......
Euphonious Thumpe


--- On Thu, 6/4/09, John Ross <jrpiano at win.eastlink.ca> wrote:

> From: John Ross <jrpiano at win.eastlink.ca>
> Subject: Re: [pianotech] Pumper Flap Valve Leather
> To: pianotech at ptg.org
> Date: Thursday, June 4, 2009, 1:21 PM
> The originals, which will be
> replaced, have a  piece of wood attached to one 
> end, and a piece of wire attached and bent to put pressure
> on the flap.
> I have seen some with a coil spring attached to each
> corner.  Most, if not 
> all of the 4 spring type had a tin section over the flap.
> Good point about the stretch  being one way.
> Thanks, as always to the list.
> Sorry I won't be seeing any of you at the convention this
> year, but the Las 
> Vegas venue for next year, sounds like another reason for a
> drive out.
> John Ross
> Windsor, Nova Scotia
> ----- Original Message ----- 
> From: "Ron Nossaman" <rnossaman at cox.net>
> To: <al at pebworths.com>;
> <pianotech at ptg.org>
> Sent: Thursday, June 04, 2009 1:47 PM
> Subject: Re: [pianotech] Pumper Flap Valve Leather
> 
> 
> Al Pebworth wrote:
> > Hi John,
> >
> > I recently restored a Mason & Hamlin Reed Organ,
> and installed new flap
> > valve leather.  I got a big surprise!  Organ
> lost vacuum, I went on a
> > 100 mile service call, found that all of the flap
> valves had expanded,
> > about 1/4 inch in length, so would not seal.
> >
> > As the inside valves were also not sealing, I had to
> bring it back into
> > the shop to fix.  Now I have lost a lot of
> profit!!  I did notice that
> > this leather was a bit thicker than what I had used in
> the past.  I know
> > that the flaps were tight when I put the in. 
> I'll put springs on them
> > this time, or use a thinner leather with blued spring
> steel over it,
> > like is found in a Seeburg Coin Piano, and some other
> players.
> >
> > Al
> 
> John, Al,
> Leather, you likely already know, will stretch more in one
> direction than in another. I've always cut organ flap
> valves
> so the stretch is minimal along the length of the strip.
> The
> valves will "cup" some across their width, but don't get
> longer and go slack. Of course, now that I've said that...
> 
> Springs are very good cheap insurance too.
> Ron N
> 
>