A molding method and apparatus includes movable die 30 and fixed die 20
which form cavity 50, and extrusion plate 40 movable in the die
closing/opening direction. A die surface 32b corresponding to the
undercut portion is formed by separate push-up block 32, which is fixed
to push-up pin 42, which is tiltably held by extrusion plate 40, and
passes through insertion hole 34 in movable die 30. A gap 34a enables
push-up pin 42 to tilt in the insertion hole. Push-up block 32 releases
the part from the movable die by relative movement between extrusion
plate 40 and movable die 30, and, by further movement of the part, the
slanted surface of the undercut portion pushes the die surface of the
push-up block in a direction which intersects with the die
closing/opening direction to free the undercut portion by tilting the
push-up pin and push-up block.