Eptek Tooling Materials (Shanghai) Co. Ltd. (Eptek), a Chinese manufacturer of tooling materials, has developed a precision‑cast polyurethane and epoxy tooling board technology that replaces traditional spliced board construction for large, complex molds and models.
Conventional tooling boards are supplied as standard rectangular slabs. For large parts or deep cavities, manufacturers must cut, glue, cure and finish multiple sections. This splicing creates bondlines that differ from the base material in hardness, thermal expansion and sanding behavior. Even after filling and painting, seams can reappear on high‑gloss or Class A surfaces, especially after temperature cycling. Glue joints also become potential leak paths in vacuum‑forming and composite layup tooling, and adhesive layers are weak points that can crack or delaminate under repeated loads. In addition, splicing requires multiple steps — cutting, gluing, clamping, curing and seam finishing — which add time and labor.
Eptek’s alternative uses a close‑contour casting process. Starting from the customer’s 3D data, the company designs a dedicated cavity and injects liquid polyurethane (PUcast) or epoxy (EPcast) resin to form a single, monolithic blank that closely follows the final part contour. Only minimal machining allowance is left, reducing roughing time — in some cases by more than 50%. For thick‑wall or high‑temperature applications, staged curing and post-curing are applied to minimize internal stress and stabilize dimensions.
The cast blanks eliminate bondlines entirely, offering continuous surfaces, better vacuum integrity and longer service life compared with spliced boards. While standard board stock remains economical for small, simple parts, the casting approach becomes more efficient for large, curved or vacuum‑sealed workpieces.
In automotive model‑making, which accounts for about half of Eptek’s projects, the cast tooling boards are used for full‑vehicle styling models, data control models, interior/exterior trim tooling and check fixtures. The seamless blanks allow Class A surface evaluation without seam telegraphing.
In aerospace applications — also about 50% of the portfolio — the material serves as transition mold blanks for composite parts such as wing skins, fuselage panels and doors. It is also used for vacuum milling fixtures, stretch‑forming dies for sheet metal and inspection tooling. The monolithic structure eliminates leak paths across the tool surface.
Eptek offers a full product range, including PUcast and EPcast cast systems, PUboard and EPboard board stock, lightweight PUfoam cores, EPmold paste and prepreg systems, iClay styling clay and water‑soluble core material for hollow composite structures. According to the company, the core philosophy is simple: “One less splice, one more measure of manufacturing certainty.”
