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		Reaming - Course: Techniques for machining of material. Trainees' handbook of lessons (Institut für Berufliche Entwicklung, 21 p.)
			(introduction...)
			1. Purpose of reaming
			2. Design and types of reamers
			3. Preparation for reaming
			4. Reaming with solid reamer
			5. Reaming with floating reamer
			6. Reaming of taper holes
			Table 1 - Recommended values for machining allowances
			Table 2 - Usual kinds of fits

5. Reaming with floating reamer

“Reaming with floating reamer” is also a method of finishing close-tolerance holes by means of a reamer. Unlike reaming with solid reamer, however, the tool is not directly held in the tail-stock sleeve of the lathe but through a floating holder (see Fig. 14) connecting the reamer with the tailstock sleeve. The cutting is done on the inner surface of the part in its centre of rotation.

A pre-machined hole is a pre-condition.

- Here, too, all types of machine reamers can be used. For the selection of the actual reamer to be used it is important to know whether the hole is a stepped hole or blind hole (short lead of reamer; use as per Fig. 7) or a through hole.
- The use of the floating holder allows for compensation of minor offset between the axes of the workpiece and of the tool. Greater differences are to be corrected as per Fig. 13.
- The demand on the part’s true-running accuracy is relatively low, however the runout must not be greater than the floating movement of the floating holder.
- The floating sleeve must be retained by the locking bolt during reaming.
- The use of the floating holder permits quick change of reamers for holes of different sizes in one part.
- The working feed is manually effected and is to be guided smoothly.