Actual piano question: Pin strength and chipboard Yamahas

[Marcel Carey]

Hello Gordon,

I have a friend in Toronto who had such a test made on tuning pins.
It's called a Rockwell test. Rockwell is a steel strenght test. The
results were not surprising. Fly brand came up first, then denro and
Yamaha were kind of down, not to say the least. One thing we have to
remember is that Asian piano builders rely on #1 metric tuning pins
which are kind of small diameter. Add that to the softness of the
stell they use and we get the problem you described. I find some
bottom of the line Young Chang even worse for that feeling.

Marcel Carey, RPT
Sherbrooke, QC

>      It did, though, cause me to have great sympathy
> for the factory tuner who shared his distress over
> pin-setting with us recently, as the pins were
> extremely tight, and half of the job ( at least! ) was
> in attempting to get clean unisons by relieving
> torsion. It was very hard to get a clean unison, and
> whether it will hold is anybody's guess, as the
> slightest hammer preessure seemed to induce twist.
>    Which made me wonder: Has anyone done a systematic
> test of all the available pin brands for torsion? This
> would be quite easy if one had accesss to a
> metallurgical lab (University?) where those gadgets
> which twist samples until they break are used. I would
> imagine that the pin with the highest twist-breaking
> strength and the most uniform diameter would be my
> choice!