Was Buttr. Arch. Q for Ron N - increasing rim density

[Fenton Murray]

Ron O.
I'm re-reading your post and want to thank you for this technique. I can see
how this would work in many situations. Sort of like the old epoxy repair
for bridges where the hole is filled and the pin re-inserted.
Fenton
----- Original Message ----- 
From: "Fenton Murray" <fmurray at cruzio.com>
To: "Pianotech List" <pianotech at ptg.org>
Sent: Thursday, April 20, 2006 9:54 AM
Subject: Re: Was Buttr. Arch. Q for Ron N - increasing rim density


> Right back at you, Ron O.
> ----- Original Message ----- 
> From: "Overs Pianos" <sec at overspianos.com.au>
> To: "Pianotech List" <pianotech at ptg.org>
> Sent: Sunday, April 16, 2006 4:14 PM
> Subject: Was Buttr. Arch. Q for Ron N - increasing rim density
>
>
> > Fenton and all,
> >
> > At 6:57 AM -0700 16/4/06, Fenton Murray wrote:
> > >How about treating the inner rim with a penetrating epoxy?
> >
> > Yes that would work, but you need some means of hydraulically driving
> > the glue into the wood. A slightly less messy solution, which I've
> > used for light density rims such as Luaun, is to drill a series of
> > holes into the top face of the inner rim, spacing them about 12 mm or
> > 0.5" apart around the perimeter, drilled to a depth of around 25 mm.
> > The drill diameter is chosen such that the resultant holes are a
> > slight press fit for maple hammer shanks (a couple of test samples in
> > a piece of scrap will allow you to determine which drill size is the
> > most suitable). The drill must be very sharp or it will glaze the
> > surface of the hole, preventing glue from moving into the wood pores.
> > For this type of work it is most important to have a series of drills
> > in 0.1 mm diameter increments from which to choose. We have drill
> > sizes from 1.0 to 10.00 mm in 0.1 mm  steps. They can be purchased at
> > quite reasonable prices in sets. One set from 1.0 - 6.0 mm, and a
> > second set from 6.0 - 10.00 mm. Fill the holes right to the top with
> > Titebond and drive the hammer shanks home to the bottom of the holes.
> > Glue comes out of wood pores everywhere. The clean up is very easy
> > compared to epoxy and the density increase overall is fantastic. A
> > Japanese pull-saw can be used for trimming the excess hammer shank
> > length flush with the top surface of the inner rim after gluing.
> >
> > If the belly rail is similarly light-weight, it can be treated in the
> > same manner. Its quite an effective fix for pianos which were built
> > using trash-wood for the inner rim.
> >
> > If you use this method, don't forget to leave the case for a couple
> > of weeks to dry out before fitting the new sound board, or it will
> > take ages for the piano to normalise after the rebuild.
> >
> > This technique, for hydraulically driving glue, can be used for
> > bolstering back beam joints by drilling holes which diagonally
> > intersect joints, including back beam joints with the rim/belly rail.
> > Before a case is fitted with a new board all joints can be 'injected'
> > using this method from above and below to make sure that the entire
> > length of the joints are 'sound' (flip the case and treat the lower
> > part of the joints, then set it right way up to treat the top part of
> > the joints - all before fitting the sound board). Once you try this
> > it will surprise you how many joints, which look to be OK, really had
> > gaps all over the shop. I suspect that poor back brace joints will
> > suck up energy which might otherwise be helping the sustaining
> > qualities of an instrument.
> >
> > Look forward to meeting you in Rochester Fenton.
> >
> > Ron O.
> > -- 
> > OVERS PIANOS - SYDNEY
> >     Grand Piano Manufacturers
> > _______________________
> >
> > Web http://overspianos.com.au
> > mailto:ron at overspianos.com.au
> > _______________________
> >
> >
>
>
>