About this detail of the Tiger
Trumpeter have applied a subtle texture to many of the surfaces in this kit, simulating the finish of rolled or cast steel. In many places you will not see this finish because it will be concealed by whatever Zimmerit you apply. But these Tigers were not completely covered in Zimmerit.
Unfortunately, Trumpeter applied the rough texture to parts that did not have it. Some of them were machined, others were castings, but all had a much smoother finish than what's in the kit.
The parts in this kit that have a too-rough texture include: the crew hull hatches; the hull MG housing; the driver's visor armour; the sprocket face; the cupola; the idler rims.