Methods and systems for creating cold plates are disclosed. For example, in one example method for manufacturing a cold plate made of a thermally-conductive plastic includes performing a first injection-molding process using the thermally-conductive plastic to produce a first unitary body, the first unitary body including one or more elongated sections forming a unitary body, performing a second injection-molding process using the thermally-conductive plastic to produce a second unitary body, the second unitary body incorporating the first unitary body so as to cover a majority of the first unitary body and form a respective coolant pipe body corresponding to each elongated section, and performing a machining process on the second unitary body so as to create a conduit in each respective coolant pipe body suitable for a fluid to pass through to create respective coolant pipes.