string termination

[Farrell]

Terry wrote:
>> Why not use other termination types like a capo-type bar in all string 
>> sections like you see on cheap old American microgrands? What about 
>> something more like an upright pressure bar arrangement?

Ron N replied:
> Actually, it looks to me to be quite possible to retrofit an agraffed 
> piano with a termination bar of harder material than the brass agraffe, 
> along the agraffe line, with a pressure bar behind, screwed into the 
> plate. A cast stepped bar would be ideal for matching speaking lengths 
> within the unison, but I'm curious how well a curved bar would work. Just 
> how critical are slightly mismatched speaking lengths within unisons at 
> those string lengths? I'd guess there is some tolerance.

I guess so. Seems to me we have a lot of uprights around to give us a clue 
how that would work.

But if that is a concern (and I suspect it is) and we are retrofitting 
something anyway, what about a stepped arrangement of small bars of hard 
material. Think of that Baldwin R you remanufactured a little while ago. The 
rear duplex arrangement. It was just little round loose bar sections laying 
on the plate (talk about a tunable rear duplex!). You could do a similar 
thing for the forward string termination in the tenor and bass. Maybe rather 
than leaving the bar loose on top of the plate, they could be epoxied in 
place in a little groove in some hard maple. Kinda like some of the 1890s 
and some newer upright pianos that have a continuous rod set on top of a 
strip of maple - do the same thing only use a stepped arrangement of short 
rods - pressure bar between pins and rods. You could even put grooves in the 
pressure bar to align strings. Or you could always come up with some sort of 
bridge-pin-like setup to provide guides for string alignment in this area.

Yeah, I know, or I could also! Well, I will.........some day.....

Terry Farrell