Broken tuning pin removal

[Ted Simmons]

While tuning a spinet last week a tuning pin broke at the becket hole
leaving most of the pin exposed.  I thought it would be a simple task to
turn the pin out of the hole and hammer in a new one, but such was not the
case.  The tuning pins on this piano are super tight and I couldn't budge
the broken pin with vise grips.  So I sawed the becket deeper and tried a
big screwdriver with no success.  Can anyone suggest a tool or a method
that will get this tuning pin out?

Ted Simmons
Merritt Island, FL