Method and apparatus for curing large composite panels

An apparatus for use in curing a composite part, comprising:

• (a) a lay-up mandrel;
• (b) a porous structural spacer overlying the lay-up mandrel, the porous structural spacer for receiving an uncured volatile-emitting composite material, wherein the porous structural spacer includes two metal mesh sheets of different density and porosity;
• and
• (c) a bagging film overlying the porous structural spacer and having at least one vacuum port to permit the flow of volatiles emitted by the composite material through the bagging film, wherein the porous structural spacer prevents mark-off by the vacuum port.

A method of forming a composite part, generally from a volatile-emitting resin comprising:

• arranging a porous structural spacer against a volatile-emitting composite material on a mandrel, the porous structural spacer having a porous network and sufficient structural strength to allow the flow of the reaction by-products to the vacuum port without causing mark-off, wherein the porous structural spacer includes two metal mesh sheets of different density and porosity;
• substantially sealing a bagging film over the composite material so as to form a reaction chamber, the reaction chamber having at least one vacuum port for egress of reaction by-products from the reaction chamber;
• and
• curing the composite material and applying vacuum through the vacuum port for withdrawing the reaction by-products.

An apparatus for use in curing a composite part generally made from a volatile-emitting resin, comprising:

• (a) a lay-up mandrel for receiving uncured composite material;
• (b) a bagging film substantially overlying over the composite material and sealing around the composite material to define a reaction chamber;
• (c) at least one vacuum port in fluid communication with the reaction chamber to permit reaction by-products emitted from the composite material during curing to escape from the reaction chamber, the vacuum port located intermediate in the bagging film;
• and
• (d) a porous structural spacer within the reaction chamber between the composite material and the vacuum port, the porous structural spacer having a porous network and sufficient structural strength to allow the flow of the reaction by-products to the vacuum port without causing mark-off, wherein the porous structural spacer includes two mesh sheets of different density and porosity.