[CAUT] Reaming block?

[Mark Cramer]

On the subject of keep on learning, did I ever post about the time I
chip-tuned an upright from the top down (C-8) with a chromatic tuner, only
to remember about 1/2 way through that it was an 85-note piano!! ?  ;>)

Reverse-grip pins I believe originated in Japan, but by now may be
universal. To be certain, we use Denro. If you hold the threaded end firmly
in cloth, it will turn significantly easier in the tightening direction than
the loosening.

My experience is that they make little difference in normal conditions, but
offer a greater degree of dependability in marginal situations.

(to forestall the usual speculations about whether these threads advance
pin-block wear or not... Yamaha and Kawai have been using them for
decades... perhaps forever?)

Sorry Alan, testing torque in the reverse direction (oops there I go again),
"with" the pull of the string, takes string tension out of the picture.

Most of us, including you and I presumeably go by feel, as 100 inch pounds
might feel snug in one pin block, but spooky in another.

However "numbers" are often helpful for our clients, so I keep an economy
torque-wrench in my kit.

When assessing a piano, "fifty inch-pounds" is my pass/fail spec. Any
tuning-pin at this point or below gets chalked. This "visual" usually speaks
louder than words, but sometimes it helps to also put the torque wrench in
the client's hands, so they can actually feel what we are talking about.

In the re-pin situation, any pin seated to final height that pulls less than
100 is typically a "fail," but within context.  i.e.: this might work in the
high treble, but definately not in the bass. The context continues to
include what that 100 pound pin might become if we upsized once more...
"manageable, or a broken stub!?"

best regards,
Mark C.





Hey Mark,

I keep on learning. To wit, what are "reverse-grip" tuning pins and where
does one find them? And presumably by "reverse direction" you mean with (not
against) the string pull.

Thanks for sharing your method.

Alan