When milling helical racks, what are the two workpiece clamping methods to ensure the helix angle β? What are their respective applications? Can the transfer distance differ between these two clamping methods during milling?
The first method involves clamping the workpiece at an angle. After clamping with this method, the reference side of the workpiece forms an angle with the direction of movement of the worktable, the angle being equal to the workpiece's helix angle β. Each movement of the worktable should be equal to the normal pitch pn of the helical rack. This method is only suitable for milling helical racks with small helix angles.
The second method involves clamping the workpiece's reference side parallel to the direction of the worktable's movement, then rotating the worktable so that it rotates the workpiece along with it through a helix angle. When milling helical racks using this rotating worktable method, the distance moved each time should be equal to the end face tooth pitch pt of the helical rack. This method is suitable for milling longer helical racks on a universal milling machine.