Tip and drill

1. A drill tip, comprising:

a first part comprising a cutting edge located at a side of a first end, and a recess located at a side of a second end, where the first end is one side of a central axis and the second end is another side of the central axis; and

a second part comprising a shank portion extending along the central axis, and an engaging portion which connects to the shank portion at a side of the first end and comprises a diameter greater than the shank portion, wherein

the engaging portion is located in the recess,

the first part comprises a through hole extending from the recess toward a side of the first end, and

the recess comprises a groove which connects to the through hole and extends toward a side of the second end.

2. The drill tip according to claim 1 ,

wherein an inner diameter of a part of the recess which is located at a side of the second end is smaller than an outer diameter of the engaging portion.

3. The drill tip according to claim 1 ,

wherein a side of the recess is a convex curved surface and a side of the engaging portion is a concave curved surface in opposing surfaces between the recess and the engaging portion which intersect with the central axis.

4. The drill tip according to claim 1 ,

wherein the first part is rotationally symmetric with respect to the central axis.

5. The drill tip according to claim 1 ,

wherein the engaging portion is located closer to a side of the second end than the cutting edge.

6. The drill tip according to claim 1 ,

wherein an end portion of the groove located at a side of the first end is located closer to the central axis than an end portion of the groove located at a side of the second end.

7. The drill tip according to claim 1 ,

wherein the second part is joined to the first part.

8. A drill, comprising:

the drill tip according to claim 1 ; and

a holder comprising a pocket at a side of the first end, and the pocket at which the drill tip is located.