A spider tool (10) for centering and stabilizing a workpiece (26) in an open spindle lathe includes a centering member (20) which engages one end of the workpiece (26). A plurality of riser pins (62) which emanate from a circular collar (50) are operable to nearly simultaneously project radially away from the collar (50) to engage the inner surface (79) of the lathe spindle (80), in response to axial movement of a shaft (86). The shaft (86) is maintained within a cylindrical housing (35) which is coupled to the collar (50) and the centering member (20).
