This paper discusses the design, manufacturing, and planned testing of a scaled demonstrator turbine as part of the Segmented Ultralight Morphing Rotor (SUMR) project funded by the Advanced Project Research Agency - Energy (ARPA-E). The scaled demonstrator (SUMR-D) is based off of a downwind, 13.2 MW SUMR design. This scaled rotor will be tested on the CART2 turbine at the National Wind Technology Center to verify the scaling methodology and planned control scheme. The design was done in an iterative fashion among six teams focused on aerodynamics, structures, and controls. This process included extensive load analysis, modification for manufacturability, adaptations required for testing on the CART2, and ground proof loading. The details of this process are presented here, concluding with planned testing and expectations of performance.