If the reduced-diameter portion of a shaft (a) is to be milled, a small shoulder should be provided, if feasible, in order to prevent damage by the milling cutter to the main shoulder.

(I) Effective Broaching

As in drilling, both entrance and exit surfaces of the workpiece should be perpendicular to the workpiece, the exit side being more critical in the case of broaching. Hence, change design (a) to (C), if possible, with (b) intermediate between the two.

If two slots are needed in a tapered bore. design (a) involves two setups and two separate machining operations. If. on the other hand, the broached slots are de signed parallel to the bore axis (b), they an be produced in one setup and one operation.

Broaching slots of different widths at requires broaching cutters of different sizes. Slots of the same width, but different depths, can be machined with the same broach (b) and thus save on tooling.

Unsymmetrical part design leads to tool deflection and extra load. A symmetrical design (b) is preferable.