TAP WITH UNDERCUTTING

摘要

There is a tap, the threaded part 2 of which forms a cutting part 5 and a guide part 6 and is provided with an undercut 8 on a plurality of adjacent thread teeth of the cutting part 5. It is desirable if there be provided for the tap a further machining measure, by means of which advantageous compromises as regards guidance and friction can be obtained. This is achieved in that the undercut 8 of the adjacent thread teeth of the cutting part 5 changes with an increase or a decrease in its clearance angle, as seen in the longitudinal direction. As a result of the change of the undercut, the requirements regarding the prevention of miscutting and the prevention of friction-related cold welding can be satisfied and coordinated with one another in an improved manner.