in order to accommodate a large milling cutter or grinding wheel (a), the relief groove may need to be quite long (b).

To provide relief for an internal, blind keyway (a), the design may include a hole (b), or an internally bored groove (c). The latter Is expensive, but may be desirable when there are several circumferentially disposed keyways (as in a spline), or when drilled holes are not feasible.

Tapered surfaces require ample tool clearance. For this reason the shoulder in (a) Is best avoided as in (b).

Another illustration: for the tapered surface in (a), grinding-wheel clearance Is increased by providing a neck in the attached shaft (b).

(d) Effective Clamping in Machining and Assembly

When it is impossible to grip or hold a part for machining (a), extra metal can be added (b) and removed (machined off) after completion of machining.

Sometimes clamping is achieved by permanent metal deformation--in this case from a tapered surface (a) to a cylindrical surface (b).