Washerless cutting tool assembly

1. A washerless cutting tool assembly, comprising:

a cutting tool holder having a central, longitudinal axis; and

a rotatable cutting tool at least partially disposed within the cutting tool holder, the rotatable cutting tool having a central, longitudinal axis and including a cutting tool body having a head portion and a shank portion axially rearward of the head portion, the head portion and the shank portion capable of being rotated about the central, longitudinal axis, the head portion including a cutting member at an axial forward end thereof, a bolster portion axially rearward of the cutting member and a base portion at an axial rearward end of the head portion, the bolster portion including a convex shape section having a socket at an axial forward end thereof, the cutting member being affixed to the cutting tool body within the socket,

wherein the cutting tool holder includes a protrusion at an axial forward end thereof,

wherein the rotatable cutting tool includes a groove at an axial rearward end of the head portion, the groove capable of receiving the protrusion of the cutting tool holder to align the central, longitudinal axis of rotatable cutting tool with the central, longitudinal axis of the cutting tool holder, and

wherein the shank portion includes a limited rotation feature comprising a braking ring disposed within the annular groove in the shank portion, and a retainer ring disposed over the braking ring to limit rotation of the rotating cutting tool during operation.

2. The washerless cutting tool assembly of claim 1 , wherein the protrusion of the cutting tool holder is disposed between a chamfered surface and a radial support surface, and wherein the groove of the rotatable cutting tool is disposed between a chamfered surface and a radial support surface that cooperate with the chamfered surface and the radial support surface of the cutting tool holder.

3. The washerless cutting tool assembly of claim 1 , wherein the bolster portion further includes a generally cylindrical section contiguous with the convex shape section, and wherein the head portion has an axial length dimension, H, the convex shape section has an axial length dimension, X, and the generally cylindrical section has an axial length dimension Y, the ratio (X+Y)/H being in the range of 0.25 to about 0.80.

4. The washerless cutting tool assembly of claim 3 , wherein the ratio Y/X is in the range of about 0.05 to about 1.0.

5. The washerless cutting tool assembly of claim 3 , wherein the convex shape section of the bolster portion has a radius, R, in the range of about 0.85 inches to about 1.4 inches.

6. The washerless cutting tool assembly of claim 1 , wherein the cutting member includes a substrate and a layer of super hard material adhered to the substrate.

7. The washerless cutting tool assembly of claim 6 , wherein the substrate of the cutting member includes a sidewall that tapers in an axial rearward direction.

8. The washerless cutting tool assembly of claim 7 , wherein the socket includes a sidewall configured for receiving the substrate of the cutting member.

9. A rotatable cutting tool comprising a cutting tool body having a head portion and a shank portion axially rearward of the head portion, the head portion and the shank portion capable of being rotated about a central, longitudinal axis, the head portion including a cutting member at an axial forward end thereof, a bolster portion axially rearward of the cutting member and a base portion at an axial rearward end of the head portion, the bolster portion including a convex shape section having a socket at an axial forward end thereof, the cutting member being affixed to the cutting tool body within the socket,

wherein the rotatable cutting tool includes a groove at an axial rearward end of the head portion, the groove capable of receiving a protrusion of a cutting tool holder to align the central, longitudinal axis of the rotatable cutting tool with a central, longitudinal axis of the cutting tool holder, and

wherein the shank portion includes a limited rotation feature comprising a braking ring disposed within the annular groove in the shank portion, and a retainer ring disposed over the braking ring to limit rotation of the rotating cutting tool during operation.

10. The rotatable cutting tool of claim 9 , wherein the groove of the rotatable cutting tool is disposed between a chamfered surface and a radial support surface that cooperate with a chamfered surface and a radial support surface of the cutting tool holder.

11. The rotatable cutting tool of claim 9 , wherein the bolster portion further includes a generally cylindrical section contiguous with the convex shape section, and wherein the head portion has an axial length dimension, H, the convex shape section has an axial length dimension, X, and the generally cylindrical section has an axial length dimension Y, the ratio (X+Y)/H being in the range of 0.25 to about 0.80.

12. The rotatable cutting tool of claim 11 , wherein the ratio Y/X is in the range of about 0.05 to about 1.0.

13. The rotatable cutting tool of claim 11 , wherein the convex shape section of the bolster portion has a radius, R, in the range of about 0.85 inches to about 1.4 inches.

14. The rotatable cutting tool of claim 9 , wherein the cutting member includes a substrate and a layer of super hard material adhered to the substrate.

15. The rotatable cutting tool of claim 14 , wherein the substrate of the cutting member includes a sidewall that tapers in an axial rearward direction.

16. The rotatable cutting tool of claim 15 , wherein the socket includes a sidewall configured for receiving the substrate of the cutting member.