seeking clarity, was relevance of bridge pin spacing

Ron Nossaman rnossaman at cox.net
Tue Jan 1 13:43:37 MST 2008


> If I change the front to rear bridge pin spacing using my jig/patterns 
> (I can design them to maintain consistent string offset) and strive to 
> position the front pins for the same scaling reasons, is this not the 
> same thing? 

Another Ron -
It is the same thing. This is what I do with my three 
different spacing jig/punches. In my case, using my 18mm 
spread as "standard", I find I don't have to go narrower than 
16mm, or above 20mm to avoid conflicting pins.


> Regarding scaling I use PScale. When I plug in my ideal scale with 53mm 
> at note 88 the tension is flagged as high (above 66% brake point) for 
> the top 3 or 4 notes using .032 wire. This piano had no evidence of 
> broken strings (originals were old and rusted - probably original). It 
> should be safe to stick with this scheme? Going to a larger wire size 
> does not appear to help nor do I think it would be a good idea. 

Sanderson's formula puts a 53mm C-8 at about 70% break. That 
break% will be essentially the same whatever size wire is 
used, but the tensions will change with a change in wire size.


>When Ron 
> refers to "smaller radiused hardened bars" he is refering to capo and a 
> pressure or bearing bar above it?
> 
> Gene

Yes. Ron O hardens both the capo and the counter bearing.
Ron N


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