The project was undertaken at the Boeing Tooling Center in St. Louis. The LCTC process uses an aluminum honeycomb substructure in combination with RenPaste RP 4040 syntactic epoxy patties from RenShape Solutions, the tooling arm of Vantico Inc. Adhesive and Tooling Div. (East Lansing, MI). This provides a cost-effective rapid tooling system. The resulting models can be machined directly from computer-aided design (CAD) data and can withstand temperatures of up to 193 C for the initial supported cure of prepreg parts.
Boeing Rotorcraft and Vantico created the LCTC process. The objective of the research was to develop a method for building economical, precision models for producing up to 10 composite parts. The project called for a sag-resistant tooling paste that did not require freezing storage, exhibited a coefficient of thermal expansion comparable to aluminum, a heat-up rate similar to composite tooling and the ability to perform during intermediate-temperature autoclave cycling. RP 4040 epoxy patties fit the requirements for fabricating models and tools directly from CAD data.