The Align gradings to grain axis function can be used if the grain axis is graded. This function, applied after selecting the piece(s), allows choosing, during the next step, the options for packing on direction
By default, the alignment is set to be applied on both directions: X and Y, you being able to also use only one of the options to pack on direction. Confirm the packing of the grain axis’s grading by clicking on Validate or by pressing Enter.