The thread milling process produces relatively low cutting forces, but never-the-less, the rigidity of the workpiece must be carefully considered and observed.

Vibrations and oscillating movements are generated from the interrupted cutting process of the milling cutter, and directly affects thread finish, tool life, and even the possibility of chipped or broken tools.

Weak workpieces and workpieces which protrude too far out of the machine, must be supported so that vibrations do not occur and that the workpiece does not begin to oscillate. In general, the workpiece should be clamped as close to the machine table as possible to ensure the highest rigidity and security when cutting.

Also important, is to observe that thin-walled workpieces are not deformed through high clamping pressures, because after the cutting process has been finished, the workpiece can take its original form and leave an oval or polygon thread.