A mandrel assembly for manufacturing a CMC turbine blade, the mandrel assembly comprising: a tip section including a pressure side and a suction side; a root section including a pressure side and a suction side; and a plurality of ceramic matrix composite plies laid up from one side to the other across a cross section of the mandrel assembly and interposed between the tip section and the root section; characterized by the plurality of CMC plies defining a reinforcement lattice structure within the CMC turbine blade, wherein the tip section comprises a leading edge part connected to a trailing edge part, and wherein the root section comprises a leading edge part connected to a trailing edge part; and wherein one of the leading edge part of the tip section and the leading edge part of the root section comprises a connector on an end facing the other of the leading edge part of the tip section and the leading edge part of the root section, and wherein the other of the leading edge part of the tip section and the leading edge part of the root section comprises a connector receiver on an end facing the one of the leading edge part of the tip section and the leading edge part of the root section, and wherein one of the trailing edge part of the tip section and the trailing edge part of the root section comprises a connector on an end facing the other of the trailing edge part of the tip section and the trailing edge part of the root section, and wherein the other of the trailing edge part of the tip section and the trailing edge part of the root section comprises a connector receiver on an end facing the one of the trailing edge part of the tip section and the trailing edge part of the root section, the plurality of CMC plies each including an alignment opening through which respective ones of the connectors are disposed in engagement with the connector receivers. a tip section including a pressure side and a suction side; a root section including a pressure side and a suction side; and a plurality of ceramic matrix composite plies laid up from one side to the other across a cross section of the mandrel assembly and interposed between the tip section and the root section; characterized by the plurality of CMC plies defining a reinforcement lattice structure within the CMC turbine blade, wherein the tip section comprises a leading edge part connected to a trailing edge part, and wherein the root section comprises a leading edge part connected to a trailing edge part; and wherein one of the leading edge part of the tip section and the leading edge part of the root section comprises a connector on an end facing the other of the leading edge part of the tip section and the leading edge part of the root section, and wherein the other of the leading edge part of the tip section and the leading edge part of the root section comprises a connector receiver on an end facing the one of the leading edge part of the tip section and the leading edge part of the root section, and wherein one of the trailing edge part of the tip section and the trailing edge part of the root section comprises a connector on an end facing the other of the trailing edge part of the tip section and the trailing edge part of the root section, and wherein the other of the trailing edge part of the tip section and the trailing edge part of the root section comprises a connector receiver on an end facing the one of the trailing edge part of the tip section and the trailing edge part of the root section, the plurality of CMC plies each including an alignment opening through which respective ones of the connectors are disposed in engagement with the connector receivers.