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		Recessing, Cutting-out and Cutting-off - Course: Techniques for machining of material. Trainees' handbook of lessons (Institut für Berufliche Entwicklung, 17 p.)
			(introduction...)
			1. Purpose and importance of recessing, cutting-out and cutting-off
			2. Design and types of turning tools to be used
			3. Preparation of recessing, cutting-out and cutting-off
			4. Recessing of external and internal grooves
			5. Cutting-out of disks and rings
			6. Cutting-off of solid stock and hollow parts

6. Cutting-off of solid stock and hollow parts

The cutting-off technique involves machining of the workpieces on the circumferential surface towards the axis of rotation until the workpiece is parted.

The right-hand end-cut turning tool is mostly used.

The cutting-off technique as metal-cutting operation is a highly economical way of parting workpieces.

- The parts to be machined are held in a chuck in hard chuck jaws.
- When cutting-off into solid stock, the turning tool works under similar conditions as with facing of a disk, i.e. the diameter is reduced and, with constant rotational speed, the cutting speed is reduced, too.

Figure 17 Facing of a disk

With constant rotational speed - reduction in diameter - cutting speed approaching 0.

- With the turning tool approaching the centre, the cutting speed is approaching the value zero.
- The spindle bearing of the lathe must be free from play to avoid hooking and breakage of the turning tool.
- The primary cutting edge of the end-cut turning tool is to be ground slightly obliquely so that no parting-off flash will be left on the cut-off part. (Fig. 5 in section 2).