Swivel friction

Made a ball-screw connection. Scrolls normally. We assembled a node with two identical connections, applied an axial load. One connection works fine and the other doesn't work at all. Removed from the second compound ball. Everything worked.

The reason is that the groove under the ball is slightly larger than the ball and with a dense stuffing of balls, they lie in a zigzag. Under axial load, adjacent grooves try to set the balls in the same plane, and the balls rest against each other. The rolling friction was gone, and the sliding friction prevented the parts from turning.