A method of manufacturing a composite part, the method comprising: characterizing a resin reference signature of a first composite preform, characterizing the resin reference signature comprising: locating an open circuit approximate a resinous member; applying a direct current to the open circuit; subjecting the resinous member and the open circuit to a curing cycle, such that the resinous member contacts and bridges the open circuit as the resinous member melts, thereby providing a conductive path through the open circuit; locating a filter adjacent the open circuit to prevent conductive particulate matter from shorting the open circuit, the filter configured to allow the resinous member to bleed through the filter and contact the open circuit; and measuring the direct current traveling through the resinous member during the curing cycle, wherein the open circuit is interdigitated having a plurality of conductor tracks (404a, 404b), each of the plurality of conductor tracks (404a, 404b) being adjacent to the same side of the filter; assembling a second composite preform with a resinous material and an open circuit; measuring the direct current traveling through the resinous material of the second composite preform during a curing cycle; and selectively controlling a manufacturing variable of the second composite preform in response to the step of measuring the direct current traveling through the resinous material during the curing cycle based on the resin reference signature of the first composite preform; wherein the step of selectively controlling a manufacturing variable includes: (i) decreasing a heating rate during the curing cycle when the current through the resin indicates that the resin is curing too quickly; and/or (ii) increasing a heating rate during the curing cycle when the current through the resin indicates that the resin is curing too slowly. characterizing a resin reference signature of a first composite preform, characterizing the resin reference signature comprising: locating an open circuit approximate a resinous member; applying a direct current to the open circuit; subjecting the resinous member and the open circuit to a curing cycle, such that the resinous member contacts and bridges the open circuit as the resinous member melts, thereby providing a conductive path through the open circuit; locating a filter adjacent the open circuit to prevent conductive particulate matter from shorting the open circuit, the filter configured to allow the resinous member to bleed through the filter and contact the open circuit; and measuring the direct current traveling through the resinous member during the curing cycle, wherein the open circuit is interdigitated having a plurality of conductor tracks (404a, 404b), each of the plurality of conductor tracks (404a, 404b) being adjacent to the same side of the filter; locating an open circuit approximate a resinous member; applying a direct current to the open circuit; subjecting the resinous member and the open circuit to a curing cycle, such that the resinous member contacts and bridges the open circuit as the resinous member melts, thereby providing a conductive path through the open circuit; locating a filter adjacent the open circuit to prevent conductive particulate matter from shorting the open circuit, the filter configured to allow the resinous member to bleed through the filter and contact the open circuit; and measuring the direct current traveling through the resinous member during the curing cycle, wherein the open circuit is interdigitated having a plurality of conductor tracks (404a, 404b), each of the plurality of conductor tracks (404a, 404b) being adjacent to the same side of the filter; assembling a second composite preform with a resinous material and an open circuit; measuring the direct current traveling through the resinous material of the second composite preform during a curing cycle; and selectively controlling a manufacturing variable of the second composite preform in response to the step of measuring the direct current traveling through the resinous material during the curing cycle based on the resin reference signature of the first composite preform; wherein the step of selectively controlling a manufacturing variable includes: (i) decreasing a heating rate during the curing cycle when the current through the resin indicates that the resin is curing too quickly; and/or (ii) increasing a heating rate during the curing cycle when the current through the resin indicates that the resin is curing too slowly. (i) decreasing a heating rate during the curing cycle when the current through the resin indicates that the resin is curing too quickly; and/or (ii) increasing a heating rate during the curing cycle when the current through the resin indicates that the resin is curing too slowly.