All German tank turrets were asymmetrical in some way, but usually their basic armour plate was not. The Tiger I turret was an exception; its front was considerably wider on one side. (I first reported this in Military Modelling Magazine, June 1994.)
The turret walls were a single piece of steel plate, specified as 80mm thick, with curved and straight sections.
The curved part was centered on the turret's rotational axis. The straight parts were tangential.
This is a right-side elevation. The rear of the turret was a plain cylinder. The front had a slant on its top edge, and an undercut. The position of the main gun's axis is marked here.
The forward edge of the armour was carefully shaped, relative to the gun's axis.
In this model, you can see that the forward edges of the wall are not cut perpendicularly through it; they are cut parallel to the tank's transverse axis.
[1] Drawing 3306 : "Untersuchung über Verlademöglichkeit des Tiger E"
[2] Factory drawing 2AKF31861U1B11: Turmgehause (overall turret armour)
[3] Factory drawing 2AKF31861U1B12: Turmgehause (turret front plates)
[4] Survey of Tiger 250122, at Bovington museum, by David Byrden