The slant does not have to be 7 degrees.  This it too great an angle
for many pianos.  The angle you need to be concerned about is between
the tuning pin and wire travelling to the counter bearing bar.  The
wire should leave the tuning pin at 90 degrees.  So the angle of the
pin is established by the height of the counter bearing bar.  Too acute
an angle will have the wire pulling down from the coil.  3 to 5 degrees
usually is sufficient.  90 is OK, too.

When dealing with tuning pin bushings, the punch has a point which
marks the center on the pin block when the bushings are installed.
I drill the block at the drill press out of the piano.  With the plate
out as well I turn it over and drill from the bottom at the angle at
which the tuning pin will be drilled.  This maintains the center at the
'bottom' and establishes the correct angle in the bushing.

If you didn't drill an angle in the bushing, as the pin is driven into
the pin block it will assume that angle and you could be left with a
slight space between the pin and bushing at the rear as the pin angle
changed angles.  Depending on the density of the bushing it will force
the pin towards the rear (away from the front) which could affect block
longevity because you just made the hole slightly oblong.

You could also drill the block in the piano through the bushings if you
have a table mount drill press setup for it.  However you do not want
to drill from the center at the top because the angle will cause the
pin to be close to the plate at the bottom due to the angle.  As the
pin hole wears, the pin will move closer to and eventually touch the
plate and if oversized pins are going to be installed in the future
there will be a problem.  The same holds true for pianos without
bushings.

On pianos without bushings, I also drill the plate hole at a slight
angle starting at the top.  I select a bit which is the same size as
the hole and angle the drill so as to relocate the bottom of the plate
hole further towards the rear but not make the hole wider.  (The top of
the hole is moved back as well but not as much as the bottom on the
hole).

This is done in an effort to ensure that the pin does not ride the
plate.  It is especially effective when restringing and using the old
block with larger pins.  How many times have you needed to replace the
block because the pins were riding the plate?  This is an option which
may circumvent the need to replace the block for certain pianos.

No flames, please, from the zealots who replace every block as a matter
of course.

Have a safe and pensive Veteran's Day,

Jon Page, piano technician
Harwich Port, Cape Cod, Mass.