A method for manufacturing a rotary article comprises: providing a cold metal transfer welding apparatus comprising a welding torch; providing a rotary substrate; providing a digital representation of the rotary article having at least one internal flo passage; defining a welding path on the rotary substrate based on the digital representation; rotating the rotary substrate while depositing a filler metal layer by layer on the welding path of the rotary substrate to form the rotary article; and separating the rotary substrate from the rotary article.