Systems, devices, and techniques are disclosed for forming an elongate lead body module of a modular lead. The method may comprise rotating a mandrel, wherein the mandrel extends through a through-hole of a conductor hub, wherein each conductor of a plurality of conductors extend through a respective channel of a plurality of channels of the conductor hub, wherein each conductor of the plurality of conductors extends from a respective bobbin of plurality of bobbins to the channels, wherein the plurality of bobbins are coupled to a carriage, the carriage defining a central opening through which the mandrel passes. The method may comprise moving the carriage away from the conductor hub along a length of the mandrel while the mandrel rotates causing the conductors to coil around the mandrel.