When you drive a pin out of a bored hole with a hammer the shock
compresses and causes barreling of the pin just as a rivet
shank fills the hole it's in. The harder you hammer the
tighter the pin will get.
Fred's got the right idea, pressing a pin/bolt/shaft out of a
hole is the correct way to remove them. The steady pressure
will not expand the shank, unless it is restricted at it's
exit point and you're putting a WHOLE bunch of compressive
force on it, like 22,000 psi yield strength for A36 steel.
Denny Graham
Sandwich, IL
