Watercraft lift system

1. A clamping assembly for a watercraft lifting system, the clamping assembly comprising:

a load transferring member;

a load receiving member having an outer transfer surface; and

a clamping member having

opposing flanges extending from a base portion,

an outer attachment surface of the clamping member attachable to the load transferring member, and

an inner transfer surface defined by the flanges and base portion, where the inner transfer surface is continuously curved between the opposing flanges; wherein

the clamping member supports the load receiving member such that the outer transfer surface engages a bearing surface portion of the inner transfer surface;

the outer transfer surface and the inner transfer surface are complementary and shaped such that loads are transferred from the load transferring member to the load receiving member substantially evenly at the bearing surface portion of the inner transfer surface; and

a thickness of the clamp member between the outer attachment surface and the inner transfer surface is greater at one of the opposing flanges than at the other of the opposing flanges.

2. The clamping assembly of claim 1 further comprising a tensioning assembly arranged to urge the opposing flanges toward one another and correspondingly increase a contact pressure between the outer transfer surface and the inner transfer surface, where the outer transfer surface and the inner transfer surface are shaped such that, with the clamping member supported on the load receiving member, loads are transferred from the load transferring member to the load receiving member substantially evenly across the outer transfer surface and the inner transfer surface when the tensioning assembly urges the opposing flanges toward one another.

3. The clamping assembly of claim 1 wherein the tensioning assembly includes a threaded fastener that extends through both flanges.

4. The clamping assembly of claim 1 wherein the outer transfer surface of the load receiving member is substantially parabolically-shaped.

5. The clamping assembly of claim 1 wherein a length of the clamping member cooperates with the load receiving member to distribute load from the load transfer member over approximately the length of the clamping member.

6. The clamping assembly of claim 1 wherein at least one opposing flange is attachable to the load transferring member, where the at least one opposing flange attachable to the load transferring member includes the load transferring member pivotally coupled to the flange.

7. The clamping assembly of claim 1 wherein a thickness of the clamp member between the outer attachment surface and the inner transfer surface is greater at the base portion than at the opposing flanges.

8. The clamping assembly of claim 1 wherein the outer transfer surface and inner transfer surface closely nest together such that frictional engagement between the surfaces structurally locks the clamping member onto the load receiving member.

9. A watercraft lifting system comprising:

a base frame assembly comprising

a load transferring member;

a load receiving member having an outer transfer surface, and

a clamping member having opposing flanges extending from a base portion, where

an outer attachment surface of the clamping member is attachable to the load transferring member, and

an inner transfer surface defined by the flanges and base portion, where the inner transfer surface is continuously curved between the opposing flanges, where

the clamping member supports the load receiving member such that the outer transfer surface engages a bearing surface portion of the inner transfer surface; and

the outer transfer surface and the inner transfer surface are complementary and shaped such that loads are transferred from the load transferring member to the load receiving member substantially evenly at the bearing surface portion of the inner transfer surface;

an intermediate frame assembly pivotally coupled to the load transferring member;

a bunk rail assembly pivotally coupled to the intermediate frame assembly; and

a thickness of the clamp member between the outer attachment surface and the inner transfer surface is greater at one of the opposing flanges than at the other of the opposing flanges.

10. The watercraft lifting system of claim 9 further comprising a tensioning assembly arranged to urge the opposing flanges toward one another and correspondingly increase a contact pressure between the outer transfer surface and the inner transfer surface, where the outer transfer surface and the inner transfer surface are shaped such that, with the clamping member supported on the load receiving member, loads are transferred from the load transferring member to the load receiving member substantially evenly across the outer transfer surface and the inner transfer surface when the tensioning assembly urges the opposing flanges toward one another.

11. The watercraft lifting system of claim 9 wherein the tensioning assembly includes a threaded fastener that extends through both flanges.

12. The watercraft lifting system of claim 9 wherein the outer transfer surface of the load receiving member is substantially parabolically-shaped surface.

13. The watercraft lifting system of claim 9 wherein a length of the clamping member cooperates with the load receiving member to distribute load from the load transfer member over approximately the length of the clamping member.

14. The watercraft lifting system of claim 9 wherein the at least one opposing flange is attachable to the load transferring member, where the at least one opposing flange attachable to the load transferring member includes the load transferring member pivotally coupled to the flange.

15. The watercraft lifting system of claim 9 wherein a thickness of the clamp member between the outer attachment surface and the inner transfer surface is greater at the base portion than at the opposing flanges.

16. The watercraft lifting system of claim 9 wherein the outer transfer surface and inner transfer surface closely nest together such that frictional engagement between the surfaces structurally locks the clamping member onto the load receiving member.

17. The clamping assembly of claim 1 wherein a portion of the outer attachment surface is angled relative to the inner transfer surface.

18. The watercraft lifting system of claim 9 wherein a portion of the outer attachment surface is angled relative to the inner transfer surface.