[CAUT] Soundboard mass

[Alan McCoy]

Thanks everyone for your ideas. As this bridge has been Wapinized there is
already a lot of hardware on the top and consequently little room for more
drilling. It would be easier though to go in from the top, and interesting
to hear from Del that he has found it to be more effective too. But in this
case I can see no alternative to a bottom application. Don't really like the
idea of drilling through the belly rail though.

Alan


> From: Delwin D Fandrich <fandrich at pianobuilders.com>
> Organization: Piano Design & Fabrication
> Reply-To: "College and University Technicians <caut at ptg.org>" <caut at ptg.org>
> Date: Tue, 20 Nov 2007 12:18:35 -0800
> To: 'College and University Technicians' <caut at ptg.org>
> Subject: Re: [CAUT] Soundboard mass
> 
>  
> You can do that, but there is a (probably) easier and (certainly) more
> effective
> method.
> 
> Remove a few strings around the affected area. Drill into the top of the
> bridge
> with a bit sized just a bit larger than a used lead key weight. (Careful,
> don't
> drill down into the bridge pins.) Epoxy bed the leads, including a bit of
> epoxy
> over the top. I mix in a small amount of graphite powder to make the mixture
> nice and black but still reasonably viscous. After the epoxy has cured scrape
> the surface flat and touch up with a graphite rub if necessary.
> 
> If you've not blacked the tops of the bridges mix in various fresco powders to
> color the epoxy to match the color of the bridge. Yes, it can be seen but so
> what?
> 
> Put the strings back on and try it out. You'll notice a definite increase in
> sustain, a decrease in the percussive pop at hammer strike and (probably) a
> decrease in false strings.
> 
> This is basically the method I've been describing in my various classes for
> some
> twenty plus years now. I do keep trying all those new methods I hear and/or
> read
> about but I keep going back. I find it lots easier and more effective than
> drilling all those holes down through the bellyrail, etc.
> 
> You'll find, by the way, that to achieve the same result you'll only need
> about
> half the mass that would be required if it were attached to the bottom of the
> soundboard. Ease up to the desired amount and don't over do things by going to
> far.
> 
> Del
> 
> 
> | -----Original Message-----
> | From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On
> | Behalf Of Alan McCoy
> | Sent: November 20, 2007 10:43 AM
> | To: College and University Technicians <caut at ptg.org>
> | Subject: [CAUT] Soundboard mass
> | 
> | Solution: drill a hole through the keybed, up through the
> | belly rail. Hang a brass weight. I'm thinking that I'll need
> | to drill maybe a 1.25" (or maybe
> | 1.375") hole to allow some clearance for my 1.125" diameter
> | brass stock as it will be hanging down into the belly rail.
> | I don't know yet how much mass will be effective, but I'm
> | thinking that I'll try at least 100g to begin with. This is a
> | M&H BB with adequate sustain but the weight of the vice grips
> | added some body and carry to that sustain.
> 
>