Chucking reamers.(Was: Reamers, was Yamaha Pins Update)

[McNeilTom@aol.com]

Bill Ballard & List -

Chucking reamers are intended for machine use (as opposed to hand, though
that would not be a sin).  One cool thing about them is that their flutes are
not equidistantly spaced, although they appear to be evenly spaced at a quick
glance.  The purpose of this is to reduce harmonic "chatter" of the tool in
the work and produce a more perfect surface and more uniform diameter hole.
 Chucking reamers are designed for very small amounts of stock removal
(typically less than 0.010"),  essentially a finishing cut on a hole drilled
very slightly undersize.

Most chucking reamers have a cylindrical shape (no taper), except for a small
chamfer on the leading end to help the reamer center in the hole.  I can't
imagine how you'd use this tool to "start out a brand new balance rail hole".
 You could use a #27 chucking reamer (0.144") after drilling with a #28 or
9/64 drill (0.140+").  This might be especially useful if working hard maple
for a very nice hole.

  -     Tom McNeil, RPT     -
Vermont Piano Restorations