Fig. 6. Boring Tool with Inserted Cutter and Adjustable Bar
Fig. 7. Threading Tool
A parting tool of the inserted blade type is shown in [Fig. 5]. The blade B is clamped by screw S and also by the spring of the holder when the latter is clamped in the toolpost. The blade can, of course, be moved outward when necessary. [Fig. 6] shows a boring tool consisting of a holder H, a bar B that can be clamped in any position, and an inserted cutter C. With this type of boring tool, the bar can be extended beyond the holder just far enough to reach through the hole to be bored, which makes the tool very rigid. A thread tool of the holder type is shown in [Fig. 7]. The angular edge of the cutter C is accurately ground by the manufacturers, so that the tool is sharpened by simply grinding it flat on the top. As the top is ground away, the cutter is raised by turning screw S, which can also be used for setting the tool to the proper height.
Fig. 8. To avoid springing, Overhang A of Tool should not be Excessive