About this detail of the Tiger
To aim the gun, the gunner turned the turret. Coarse rotation was achieved by hydraulic drive controlled by his feet. Fine rotation was controlled by a horizontal handwheel located in front of him.
This is the handwheel in vehicle #2500031, which still survives. Its original colour was probably black. The turret position indicator is attached to the base of the unit.
These diagrams show the position of the wheel in the turret. It was bolted to a flate plate that was welded to the turret ring.
The unit was off-center from its own base plate, because of a bolt on the turret ring.
The part number of the wheel was 021 B2766-1. This number was molded prominently on most examples; for example, it is on the Bovington vehicle (# 2500122). This photo shows the tank from Saumur museum (# 2501114).
These are the precise positions of the bolt holes and the welded plate, taken from a surviving German diagram.
The wheel had a rotating handgrip underneath, with a clutch controlling a spring-loaded rod within the handle.
When the clutch was released, the rod rose up into one of 40 locking holes within the wheel housing. This example, in a surviving Tiger at Snegiri, has been damaged by an internal explosion, allowing us to see the holes.
[1] Survey of Tiger 250122, at Bovington museum, by David Byrden
[2] Survey of Tiger 251114 at Saumur, by Hilary Louis Doyle
[4] Survey of vehicle 251114, at Saumur, by Jean-Charles Breucque