[pianotech] To ream or not to ream?

[Chuck Behm]

Hi Chuck

I'm a very green tech but I'm going to respond from the hip

I think there may be some misunderstanding as to the meanings of
drilling and reaming. As I understand from my limited experience in
metal machining, simply put, a drill will cut a hole in the direction in
which you aim it while a ream will faithfully follow the center line of
a previously drilled hole. I can fully understand why one might avoid
drilling (due to the possibility of inconsistent results) but favor
reaming (because careful reaming can actually restore hole-to-hole
consistency).

Phil
(I hope I don't reamed for saying this)

Phil - You're right, in that when I say ream, I mean to clean out the pin
hole with either a reamer or a drill.
That being said, I have a set of reamers, have tried them, and never use
them. What I do use is a tuning pin drill the size of the pin I am going to
install. I start with the drill at the angle of the pins (about 7 degrees
back from the vertical), and go at speed in and out. It gives a fresh cut in
the wood, so that the new pin isn't being jammed into the old hole, which is
slick (in my opinion) from being in contact with the previous pin for a
century or so.

The torque using this method is almost always over 120 inch pounds ( I know
my torque wrench is pegged to the side). The pins are not, however, so tight
that they are jumpy or prone to breaking. I have pianos in my area that I
repinned 25 or 30 years ago, that were tight when I finished and tight now.
I like the results I get with my method. I'm sure others are happy with
their choice of methods as well.

Of the people who responded to my survey, approximately 1/3 ream (mostly
with a drill, not an actual reamer), 1/3 clean the hole with a gun barrel
brush or something similar, and the remaining 1/3 just drive the new pin
into the old hole. There really doesn't seem to be a consensus as to the
issue.

As to the other questions, most people wear a glove or gloves (I don't, but
I have very dry hands). A number use talcum powder on their hands or glove.

A few use rosin on their pins. Most go with a dry pin.

The majority of people repinning a piano that had size 2 pins will start
with 3's and go to 4's if it seems necessary. The majority of technicians
also seem to favor blued pins if it's up to them.

Anyway, thanks to the people who e-mailed me privately, or posted their
thoughts on the subject.
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