pinblock drilling

[Clyde Hollinger]

Friends,

I've been servicing a 1978 console that developed loose tuning pins over
the past several years, pretty much evenly across the piano.  I decided
as a first course of action to drive all the pins a smidgen deeper.
That worked pretty well, but I got the distinct impression as I was
going along that the tuning pins were hitting bottom in the holes.  A
pretty good whack didn't noticeably move some of them.

Is this possible?  Has anyone had opportunity to notice if a factory has
ever drilled the pinblock on a vertical too shallow?

Regards,
Clyde Hollinger