Double cut single point cutoff tool for cutting and finishing an end surface of a fuel injector pole piece

1. A method of removing a fuel injector pole piece from bar stock, the method comprising:

providing a cutoff tool having a first cutting surface and a second cutting surface separate from the first cutting surface,

causing rotation of the pole piece and bar stock about a longitudinal axis,

advancing the tool with respect to the pole piece so that the first cutting surface severs the pole piece from the bar stock and defines an unfinished end surface of the pole piece, with a certain cutting force being exerted on the tool, and

further advancing the tool with respect to the pole piece so that the second cutting surface removes material from the unfinished end surface to define a finished end surface of the pole piece, with a cutting force on the tool being substantially less than the certain cutting force.

2. The method of claim 1 , during the further advancing step, the second cutting surface removes about 0.050 mm of the material.

3. The method of claim 1 , wherein the advancing steps include advancing the tool radially with respect to the longitudinal axis.

4. The method of claim 1 , wherein the finished end surface has a generally consistent peak to valley distances of grooves left by the tool.

5. The method of claim 1 , further comprising chrome plating the finished end surface.

6. A method of removing a fuel injector pole piece from bar stock, the method comprising:

providing a cutoff tool having a first cutting surface and a second cutting surface separate from the first cutting surface,

causing rotation of the pole piece and bar stock about a longitudinal axis,

advancing the tool with respect to the pole piece so that the first cutting surface severs the pole piece from the bar stock and defines an unfinished end surface of the pole piece, with a certain cutting force being exerted on the tool, and

further advancing the tool with respect to the pole piece so that the second cutting surface removes material from the unfinished end surface to define a finished end surface of the pole piece, with a cutting force on the tool being substantially less than the certain cutting force,

wherein the providing step includes defining the first cutting surface as a radius surface between a first edge and a second edge at a distal end of the tool, the first edge being disposed generally transversely with respect to a longitudinal axis of the tool, and the second edge being disposed generally parallel to the longitudinal axis of the tool.

7. The method of claim 6 , wherein the providing step includes spacing the second cutting surface axially from the distal end, and wherein the second cutting surface is a radius surface defined between the second edge and a third edge of the tool.

8. The method of claim 7 , wherein the third edge extends a distance from the longitudinal axis of the tool greater than a distance that the second edge extends from the longitudinal axis of the tool.

9. The method of claim 7 , wherein the size of each radius surface is about 0.008 inches.

10. The method of claim 1 , wherein the finished end surface has a profile of a line of about 0.018 mm and a runout of about 0.010 mm.

11. A cutoff tool for cutting a work piece from rotating bar stock, the tool comprising:

a body,

a first cutting surface on the body, and

a second cutting surface on the body and separate from the first cutting surface,

the first cutting surface being constructed and arranged such that as the tool is advanced with respect to the work piece, the first cutting surface severs the work piece from the bar stock and defines an unfinished end surface of the work piece, with certain a cutting force being exerted on the tool, and

the second cutting surface being constructed and arranged such that as the tool is advanced further with respect to the work piece, the second cutting surface removes material from the unfinished end surface to define a finished end surface of the work piece, with a cutting force on the tool being substantially less than the certain cutting force.

12. A cutoff tool for cutting a work piece from rotating bar stock, the tool comprising:

a body,

a first cutting surface on the body, and

a second cutting surface on the body and separate from the first cutting surface,

the first cutting surface being constructed and arranged such that as the tool is advanced with respect to the work piece, the first cutting surface severs the work piece from the bar stock and defines an unfinished end surface of the work piece, with certain a cutting force being exerted on the tool, and

the second cutting surface being constructed and arranged such that as the tool is advanced further with respect to the work piece, the second cutting surface removes material from the unfinished end surface to define a finished end surface of the work piece, with a cutting force on the tool being substantially less than the certain cutting force,

wherein the first cutting surface includes a radius surface between a first edge and a second edge at a distal end of the tool, the first edge being disposed generally transversely with respect to a longitudinal axis of the tool, and the second edge being disposed generally parallel to the longitudinal axis of the tool.

13. The tool of claim 12 , wherein the second cutting surface is spaced axially from the distal end, and wherein the second cutting surface is a radius surface defined between the second edge and a third edge of the tool.

14. The tool of claim 13 , wherein the third edge extends a distance from the longitudinal axis of the tool greater than a distance that the second edge extends from the longitudinal axis of the tool.

15. The tool of claim 12 , wherein an angle between the first and second edges is about 88°.

16. The tool of claim 13 , wherein an angle between the first and third edges is about 86°.