The ornamental design for a gearcuttingtool, as shown and described.
FIG. 1 is a perspective view of a gear cutting tool.
FIG. 2 is a front elevation view thereof. A rear elevation view, a right side elevation view and a left side elevation view are identical to the front elevation view.
FIG. 3 is a top plan view thereof; and,
FIG. 4 is a bottom plan view thereof.
The broken lines shown in the drawings illustrate portions of the gear cutting tool that form no part of the claimed design.