FDM 3D Printing for Composite Tooling
FDM composite tooling offers significant advantages in terms of lead time, tool cost and simplification of tool design, fabrication and use, while enabling increased functionality and geometric complexity.
This design guide created by Stratasys provides best practices for the design, fabrication and preparation of 3D printed composite tools, as well as relevant performance characterization data.
FDM (fused deposition modeling) is becoming the technology of choice for rapid production of high-temperature (>350 °F [177 °C]), low-volume, composite lay-up and repair tools, as well as for moderate-temperature (<325 °F [163° C]) production sacrificial tooling. Relative to traditional tooling materials and methods, FDM offers significant advantages in terms of lead time, tool cost and simplification of tool design, fabrication and use, while enabling increased functionality and geometric complexity. This design guide is focused on tools for hand lay-up, but the vast majority of the principles and guidelines are applicable to other processing methods as well.
FDM lay-up tools have many similar design and use considerations as traditional tooling, particularly those with higher coefficients of thermal expansion (CTE), such as aluminum and epoxy tooling board, although the technology provides greater design capability and freedom. To ensure high-quality surface finish and vacuum integrity, post-processing of FDM tools is typically required. Tools are abraded to smooth out perceptible build lines and sealed. They then undergo a final polish, resulting in surface finishes consistent with typical industry requirements. In fact, better than 16 μin. Ra can be consistently achieved. Sealing can be performed using a range of materials depending on the specific application, including high-temperature epoxy paste and film adhesives, as well as adhesive-backed FEP films and similar materials. Once the part is sealed, common mold-release agents can be applied in preparation for lay-up. Water-based released agents are recommended.