[pianotech] S&S K52 messaroundwith thang

[Gene Nelson]

Thanks Ron,
I think that I will set up a bench test before I decide on what to do.
I got to see what this would look like and get a feel for the carving as
best as I can.
Certainly notching would be easier than agraffes.
Gene

-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Ron Nossaman
Sent: Saturday, June 09, 2012 9:03 AM
To: pianotech at ptg.org
Subject: Re: [pianotech] S&S K52 messaroundwith thang

On 6/9/2012 10:33 AM, Gene Nelson wrote:

> *** I did take the time to try out this idea of carving the bridge as
> opposed to retrofitting agraffes in order to create equal string
> lengths in the bichords. I laid out my paper string pattern and tried
> to pencil in a notching pattern onto the bridge outline that matched
> the 27 degree angle of the upper termination. The issues that I see
> are that this will tend to narrow the string spacing, decrease the
> string off-set at the bridge pins and the front and rear relief
> notches may cause interference with neighboring strings and or
> notches. Making a jig that would help scribe the 27 degree off-set
> onto the bridge at the speaking length is easy enough but I think I
> may need larger diameter bridge pins than are available to get a good
> off-set. I really do not think it will work. Gene


If you're using the pin diameter to supply offset angle, it doesn't 
matter (within reason) what angle the bridge is to the strings. The 
geometry doesn't change with bridge angle. The notch looks backward (and 
is), but the function and working room is unchanged. Making the notch 
perpendicular to the string is both unnecessary and counterproductive in 
this case. Notch to accommodate the top bearing mound so the notch is 
parallel to it, spec the same speaking length for bichords within a 
unison, and let the winding ends fall parallel to the notch and top 
bearing mound. Or, bevel the bridge instead of notching, spec the same 
speaking length for bichords in each unison, and you won't hear any 
difference.

This is not nearly as big a deal,nor as complicated, as is being presumed.
Ron N