When milling helical racks, in order to ensure the helix angle β, which two kinds of workpieces are there?

When milling a helical rack, in order to ensure the helix angle β, what are the two clamping methods for the workpiece?What are they used for?Can these two clamping methods have different offset sizes during milling?

The first method is to tilt the workpiece to clamp.After this method is clamped, the reference side of the workpiece forms an included angle with the shift direction of the worktable, and the included angle is the workpiece helix angle β.Each movement of the table should be equal to the normal pitch pn of the helical rack.This method is only suitable for milling helical racks with a small helix angle.

The second method is to clamp the reference side of the workpiece to be parallel to the moving direction of the worktable, and then turn the worktable so that the worktable drives the workpiece to rotate through a helix angle together.When milling the helical rack by this rotary table method, each shift distance should be equal to the pitch pt of the end face of the helical rack, which is suitable for milling long helical racks on a universal milling machine.