Systems for manufacturing arthroplasty jigs are disclosed. The systems include positioning components for positioning an arthroplasty jig blank in a machining device (e.g., a computer numerical control (CNC) machine). Arthroplasty jig blanks that may be used in the systems can include an arm fixture component configured to be coupled to the positioning component. Coupling the arm fixture component to the positioning component positions the jig blank body for machining by the machining device. In addition, positioning components, arthroplasty jig blanks, and methods for making arthroplasty jig blanks are disclosed.