Retainer systems for ground engaging tools

1. A lock for a ground engaging tool, comprising:

a head portion; and

a C-shaped portion extending from the head portion, the C-shaped portion defining a lock slot between two circumferential ends for receiving a portion of a support member to be locked with the ground engaging tool, the C-shaped portion further including:

an outer surface configured to be rotatably received in an inner surface of a retainer bushing;

an inner surface configured to contact the portion of the support member; and

a base extending between the outer surface and the inner surface, the base including a helical surface with a depth increasing from a first end to a second end,

wherein the first end of the helical surface is adjacent one of the two circumferential ends, and the second end of the helical surface is adjacent the other of the two circumferential ends.

2. The lock of claim 1 , wherein the base includes a planar surface extending in a plane substantially perpendicular to a lock rotation axis, and the helical surface runs from a portion of the planar surface.

3. The lock of claim 1 , wherein the helical surface has a helix angle of approximately 2.5 degrees.

4. The lock of claim 1 , wherein the outer surface of the C-shaped portion includes a recessed portion that creates a gap between the outer surface of the C-shaped portion and the inner surface of the retainer bushing when the outer surface of the C-shaped portion is rotatably received in the inner surface of the retainer bushing.

5. The lock of claim 1 , wherein the head portion includes a wall having a first surface and a second surface opposite the first surface, the head portion further including a tool interface extending from the first surface of the wall, and wherein the wall includes a through-hole having a first end opening out to the tool interface and a second end opening out to the lock slot defined by the C-shaped portion.

6. The lock of claim 1 , wherein at least a portion of the head portion and the C-shaped portion comprises zinc-plated metal.

7. A lock for a ground engaging tool, comprising:

a head portion having a tool interface for receiving a tool for applying torque about a lock rotation axis; and

a C-shaped portion extending from the head portion and defining a lock slot between two outer circumferential ends for receiving a portion of a support member, the C-shaped portion further including:

an outer surface configured to be rotatably received in an inner surface of a retainer bushing;

an inner surface configured to contact the portion of the support member; and

a base extending between the outer surface and the inner surface, the base including a sloped surface that is not parallel to a plane perpendicular to the lock rotation axis,

wherein:

the sloped surface includes a helical surface with a depth increasing from a first end to a second and; and

the first end of the helical surface is adjacent one of the two outer circumferential ends, and the second end of the helical surface, is adjacent the other of the two outer circumferential ends,

8. The lock of claim 7 , wherein the helical surface has a helix angle of approximately 2.5 degrees.

9. The lock of claim 7 , wherein the base includes a planar surface extending in a plane substantially perpendicular to the lock rotation axis, and the helical surface runs from a portion of the planar surface.

10. The lock of claim 7 , wherein the outer surface of the C-shaped portion includes a recessed portion that creates a gap between the outer surface of the C-shaped portion and the inner surface of the retainer bushing when the outer surface of the C-shaped portion is rotatably received in the inner surface of the retainer bushing.

11. The lock of claim 7 , wherein the head portion includes a wall having a first surface and a second surface opposite the first surface, the head portion further including a tool interface extending from the first surface of the wall, and wherein the wall includes a through-hole having a first end opening out to the tool interface and a second end opening out to the lock slot defined by the C-shaped portion.

12. The lock of claim 7 , wherein at least a portion of the head portion and the C-shaped portion comprises a zinc-plated surface.

13. A retainer system for a ground engaging tool, comprising:

a retainer bushing including:

an outer surface configured to mate with a lock cavity of the ground engaging tool; and

an inner surface opposite the outer surface; and

a lock including:

a head portion; and

a C-shaped portion extending from the head portion, the C-shaped portion defining a lock slot between two circumferential ends for receiving a portion of a support member to be locked with the ground engaging tool, the C-shaped portion further including:

an outer surface configured to be rotatably received in the inner surface of the retainer bushing;

an inner surface configured to contact the portion of the support member; and

a base extending between the inner and outer surfaces of the C-shaped portion, the base including a helical surface with a depth increasing from a first end to a second end,

wherein the first end of the helical surface is adjacent one of the two circumferential ends, and the second end of the helical surface is adjacent the other of the two circumferential ends.

14. The retainer system of claim 13 , wherein the helical surface has a helix angle of approximately 2.5 degrees.

15. The retainer system of claim 13 , wherein the base includes a planar surface extending in a plane substantially perpendicular to a lock rotation axis, and the helical surface runs from a portion of the planar surface.

16. The retainer system of claim 13 , wherein the outer surface of the C-shaped portion includes a recessed portion that creates a gap between the outer surface of the C-shaped portion and the inner surface of the retainer bushing when the outer surface of the C-shaped portion is rotatably received in the inner surface of the retainer bushing.