an actual piano question

[David Parkhurst]

> A proper pinblock drill is the best reamer. I'm sorry, I've forgotton the
> technical term for for the type of drill, but the angle of the fluting is
> different from a standard bit. There are more cutting spirals per inch, and the
> edges have been sharpened to help smooth the hole. Somebody jump in here and
> supply the name for it.  The reason that special reamers (such as the spoon bit
> type) are sold is because a regular drill can create spiral grooves when driven
> down into the existing hole.  This isn't the end of the world, but it isn't too
> good.
>
> Don Mannino, RPT
> 74473.624@compuserve.com

My fevered brain dreams of a truly special tool for
reaming pinblocks. It has yet to be designed. It must be
self guiding and forgiving. And if this were a perfect
world its diameter would be adjustable over a useful
range. Surely enough technicians would want one to make
its manufacture plausible.

> I don't suggest using the spoon type reamers APSCO sells. I have some but
> have never been able to get them to work. The safest method is to drill out
> with either a J bit .277 or a K bit .281. I have had good luck using a J size
> jobber bit for 4/0 pins. You may also try using strait fluted reamers. They
> are more difficult to control and you should practice on an old discarded pin
> block first. Remember that with a maple block the original hole was .257 or
> there about and received a .282 pin. Your 3/0 pins may require 5/0 pins to be
> tight especially in the bass. As a rule if a J bit is tight in the hole then
> a 4/0 pin will work. Good luck.
>
> John Hartman

I have found that metric drills 6.8, 6.9, 7.0 and 7.1 help
to fill out one's tuning pin drill collection. I don't have
their decimal equivalvents with me at the moment but they
fit right in with letter sizes I and J and K, etc.

I am wondering if it might be a good idea to resharpen the
corners of the drill's cutting edges to be slightly
rounded. Has anybody tried this?

I am a new member of the Guild (San Francisco) and would
like to take this opportunity say hello to the mailing
list.

-David Parkhurst