[pianotech] Voicing the new Mason & Hamlins

[Horace Greeley]

Hi,

For the interested, most of Dolge's patents are available online either through the U.S. Patent Office or the Library of Congress.

Best.

Horace


-----Original Message-----
From: John Delacour <JD at Pianomaker.co.uk>
Sender: pianotech-bounces at ptg.org
Date: Wed, 29 Sep 2010 22:48:40 
To: <pianotech at ptg.org>
Reply-To: pianotech at ptg.org
Subject: Re: [pianotech] Voicing the new Mason & Hamlins

At 13:14 -0700 29/09/2010, Delwin D Fandrich wrote:

>...Since then I have described the process to several hammer makers 
>(including, a few years back, Norbert Abel) but, as far as I can 
>tell, the words "cold press" still strike fear in hearts of the 
>production hammer maker. More recently I have been able to design 
>changes to the hammer presses at Young Chang so that now the 
>temperatures of the bottom cauls can all be controlled independently 
>of the temperatures of the side cauls...

At Dolge's factory, working with animal glue, about 1910 he estimated 
that two expert gluers working on a single machine were able to cover 
240 sets in 10 hours.  This was achieved, on his latest machines, but 
also on earlier machines by other makers in Europe by using removable 
cauls.  Once the pressing is done, the cauls are locked shut and 
removed from the machine to a drying room while the glue hardens. 
There is no need for any special heating apart from that required to 
prevent gelling of the glue while setting up.  In the German machine 
(ca. 1900) I am most familiar with, the cauls are very different from 
those used on the Dolge machines and relatively cheap to produce in 
quantity.

If Dolge's men (and no doubt others, using different machines) were 
able to press hammers at a rate of one set per three minutes without 
using heated cauls, I suggest that, as in so many other instances in 
our trade, a great deal of good sense and invention has simply been 
lost over the years.

I should emphasize that I am not referring to Dolge's earlier 
machines, which are very primitive and most definitely obsolete.

JD


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