Vellum Hinges

[ed440 at mindspring.com]

Kerry-

Further elaboration of your techniques would be of interest to a small number of subscribers to this list.

Can you explain what is a vellum saw?  What kind of glue do you use?  What do you do when the hinge is in the middle of a long strip of hinges?  Do you only repair full sets, or do you sometimes replace single hinges?

Thanks!

Ed Sutton


-----Original Message-----
>From: Kerry Cooper <brispiano at optushome.com.au>
>Sent: Feb 17, 2007 6:52 PM
>To: 'Pianotech List' <pianotech at ptg.org>
>Subject: RE: Vellum Hinges
>
>John Said”
>
> 
>
>I have now collected and dismantled the Blüthner damper action.  Here is a
>picture of one of the bodies.  I will report in more detail later, but the
>vellum (dry) on this action is almost exactly 0.5mm thick.  I will measure
>the slots when I have removed the hinges and everything is dry.
>
> 
>
>I would agree that such a vellum might be too thick for the hinges on early
>squares etc. but for grand damper bodies it is fine.
>
> 
>
>I would not put the damper fingers in water to remove the vellum. This
>swells the finger and can also make the abstract twist when drying. Use a
>vellum saw to cut out the old vellum, it follows the old vellum if you are
>careful. 
>
> 
>
>To find a replacement vellum, I use old drum skins, as these are of the
>thickness needed to do the job, normally around 0.15 mm. I have replace many
>sets of these hinges with great success.
>
> 
>
> 
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>
>Kerry Cooper ARPT
>
>Brisbane Piano Centre
>
>ph:    +617-3809-0652
>
>Fax:  +617-3809-4699
>
>email: brispiano at optushome.com.au
>
> 
>