The Tiger had a fully rotating 11-ton turret. It was carried on a ball-bearing race. As was standard German practice, the turret bearing ring was fixed to the inner wall of the turret and almost nothing remained on the hull top when the turret was removed.
This diagram, from Plate 65 of the Tiger Turret Manual, is a simplified view of the ball-bearing race as originally designed. The inner steel ring is fixed and the outer steel ring is moving. The overall diameter ("Außendurchmesser") is exactly 2100mm.
The centers of the balls lie on a circle of 1990mm diameter. There are 158 ball-bearings. Every second ball is load-bearing and has diameter 40mm. The rest are spacers, with diameter 39mm [4, see page 9] . (The diagram exagerrates the size difference.) The average free space between the balls was 65µm.
When assembling the ring you drop the balls in through a hole, visible at the top right of the diagram. The balls cannot escape unless the inner and outer races are aligned exactly as shown to form the hole. I don't know how the turret would be aligned in this case.
This diagram shows the a profile of the steel rings and a ball bearing. Compare it to the left side of the German sketch. The ring carries two rubber seals for underwater travel, which I have drawn in black.
The Tiger's turret was redesigned and simplified in July 1943. The requirement for the ability to submerge was dropped shortly afterwards. The rubber seals were therefore omitted from the ball-bearing race, and the steel rings were made smaller. The diagram shows the final profile of the parts.
The redesign included new ball bearings. The spacer balls were eliminated and the number of load-bearing balls was raised to 113, with each one embedded in a small loose ring of 55mm diameter [4, see page 9] . Trapped in the vertical position by the outer and inner races, these rings kept the balls apart. The mean spacing between rings was 117µm. This same ball bearing design was used in the Tiger B "serien Turm".
This 3D model shows the new ball-bearing race fixed inside the turret wall, as per the redesign. The bearings and spacer rings can be seen.
[1] Survey of vehicle 250122, Bovington, by David Byrden
[2] Survey of vehicle at Saumur, by Hilary Louis Doyle
[5] Survey of vehicle 251114, at Saumur, by Jean-Charles Breucque
[6] DW to Tiger 1