System and method of manufacturing composite core

A method of manufacturing a block of a composite core having a plurality of hexagonal shaped cells, the method comprising:nsecuring a hexagonal mandrel with a winding jig;cutting a slit of composite material to a prescribed width, the prescribed width being dependent upon a wrap angle of the slit of composite material to the hexagonal mandrel and being dependent upon a circumference of the hexagonal mandrel;orienting the slit of composite material at the wrap angle to the hexagonal mandrel, the slit having the prescribed width that is dependent upon the wrap angle and the circumference of the hexagonal mandrel, the slit of composite material having unidirectional fibers oriented in only one direction parallel with a lengthwise axis of the slit;wrapping the slit of composite material around the circumference of the mandrel starting from a first end of the mandrel, such that only a single layer of composite material is formed on the hexagonal mandrel without any material gaps in that a helical seam is formed from the abutment of a first edge portion of the slit to a second edge portion of the slit as the slit is wrapped around the hexagonal mandrel; andassembling a plurality of wrapped mandrels so that a flat portion of composite material of one wrapped mandrel is pressed against an adjacent flat portion of an adjacent wrapped mandrel, forming a wall of the hexagonal shaped cell;wherein the composite material of each wrapped mandrel includes only the slit of composite material but the cells of the block of the composite material do not have any voids since the wrapped mandrels do not have any material gaps.