[CAUT] Hardness of termination vs string breakage (was Re: restrung D)

[Ron Nossaman]

> Now this is why I think Wim was having probs with a newlyrestrungD. If 
> you don't tune the back scale or make sure the strings render when 
> stringing then as Ron just said the string render at random times. Maybe 
> a year or two or three later.

Not that much later, I think. Weeks, maybe, but likely not 
years. It has occurred to me though, that some of that initial 
pitch drop we attribute to strings stretching could very well 
be coming from the back scale. I'm still of the opinion that 
most of the pitch drop we see in new pianos and rebuilds the 
first year is from the cap crushing at the notch edge, perhaps 
some from pinblock compression at the flange, and very little 
of it from string stretching.

Consider how many times we've read (and seen) that lightly 
seating a string on the bridge often causes a rather dramatic 
pitch drop.


> On another list about backscale tuning, I remarked that I just try to 
> smooth out the sound and tension of the back scale and asked whether it 
> would be better to raise the raise the pitch of the backscale or lower 
> it in comparison to the front scale. I got no answers. From what Ron 
> says here, I think taking the hammer shank and making sure the backscale 
> pulled up to tension+ in the stringing process is essential. Then as the 
> wire stretches, the backscale won't render through after tunings. Since 
> the rendering does this randomly with humidity swings and applying the 
> principle of "going halfway there never gets you there" even if you are 
> already halfway there, logically it must mean the tuning stability sucks.
>  
> Keith Roberts

Even if you manage to get the back scale tension up without 
damaging the bridge cap, it will likely always be slightly 
higher or lower in tension than the front scale, depending on 
whether pitch is going up, or down with temperature or 
humidity swings. That's one of my basic problems with "tuned" 
duplexes. They'll never be in tune unless the string tensions 
never change, and if the string tensions never change, the 
piano will never need tuned.

Ron N