Oak persuaders -
Vol. 17 #4, Mar. 1991
Use a good, solid, oak 2 X 4 to remove segmented screw sections that are stuck on keyed or splined shafts. This allows direct force to be used without damage resulting from metal to metal contact. (Even brass persuaders can be damaging.)
See also
Extruder screw won't push out
Screw removal 1
Screw removal 2
Screw removal 3
Screw removal 4
Segmented screws