Composite tooling is fabricated with low cost dry fabrics and a neat resin
instead of expensive prepregs. Dry, three-dimensional woven joint
preforms are placed on a dry tool substrate and dry, 3D preforms are also
placed between pre-cured egg crate-like junctions. The entire tool
substrate and substrate-to-support structure joints are then
resin-infused simultaneously through the use of rota-molded tooling aids,
providing an additional reduction in cost. Tight control of resin content
and distribution with vacuum infusion is thereby provided. This process
eliminates the primary cause of structural weakness and cooling
distortion, which typically occur at the attachment interface when
existing methods are used. The preforms provide significantly greater
pull-off strengths at interfaces than do hand-laid tie plies. Issues with
tool surface durability are addressed through the use of ceramic-filled
face coat.