[pianotech] Bridges and caps [was YC Capo Bars]

[William Truitt]

Hi JD:

The Delignit bridge capping material is straight from the Schaff catalog.
It's densified beech, just like the pinblock material where the
densification comes from heat and pressure,  but not as hard.  Still harder
than the maple though.  I capped the whole bridge, bass and all of the tenor
bridge.  This was a cheap no name grand and a one time experiment.  It
seemed to work fine, but it's just too butt ugly to want to use on a good
grand.

Sauter is using horizontally laminated ebony in the top treble section.  

Will Truitt

-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of John Delacour
Sent: Monday, September 20, 2010 5:53 PM
To: pianotech at ptg.org
Subject: Re: [pianotech] Bridges and caps [was YC Capo Bars]

At 20:27 -0500 19/9/10, Ron Nossaman wrote:

>On 9/19/2010 7:48 PM, Roger Gable wrote:
>>...Is there a top quality piano using laminated bridges? I think not.
>
>Not that I know of. There's nothing at all inherently sub standard 
>about horizontally laminated bridges, except the waste cutting them 
>out of bigger panels...

Hmm.  You're all talking exclusively of horizontally laminated 
bridges I presume and not vertically laminated as used by Steinway? 
I'd need to have more detailed evidence and analysis than a few 
expressions of opinion to convince me...

... but with regard to the Delignit bridge-capping material,  I'd 
like to hear a  fuller description of this than I see in Schaff's 
catalogue.  Is it of beech?  How thick are the laminations?  Is the 
wood impregnated to render it harder?

I can imagine that laminated hornbeam might be very effective.  The 
trouble with solid hornbeam, as I know from trying it, is that it has 
hardly any give and can easily split.  I have seen hornbeam capping 
occasionally in the treble of some  pianos, and certain high-class 
makers used boxwood for the top section, but that is now impossible 
to obtain at an economic price.

When you cap the bridge with the Delignit stuff do you do the whole 
bridge or just the top section plus?  Even the very finest of 
piano-makers from the good old days seem to have seen no virtue in 
using the harder bridge top below a certain point in the scale.

JD