Fused Deposition Modeling Design Guide

These guidelines are to be used as a starting point in understanding the basic aspects of part design and preparation for Fused Deposition Modeling components. When designing a part to be built using FDM technology, build process must be considered. FDM is accomplished by extruding thin layers of molten thermoplastic layer by layer until a part is produced. Because FDM produces parts with specific characteristics and capabilities different from those of other prototyping processes, the systems have become increasingly used as a tool for producing manufactured products.

Part Design for FDM

These guidelines are to be used as a starting point in understanding the basic aspects of part design and preparation for FDM components. When designing a part to be built using FDM technology, build process must be considered. FDM is accomplished by extruding thin layers of molten thermoplastic layer by layer until a part is produced. Because FDM produces parts with specific characteristics and capabilities different from those of other prototyping processes, the systems have become increasingly used as a tool for producing manufactured products.

Size and Orientation 

Stratasys Direct Manufacturing can make single FDM parts as large as 36 in. x 24 in. x 36 in. (X, Y, and Z). Designers should note that extruded plastic has its strongest strength in the tensile mode along the x-y plane. Since the layers are held together by “hot flow” across the strands (one strand is cooling while the other is laid upon it), the lowest strength is in the Z-direction for both tensile and shear modes. The Z-dimension brings another consideration to the FDM process. Overhanging non-supported features, such as the top of a closed box, require a foundation of support material to be built, which increases build time and material usage.

FDM Design Considerations 

The following information builds from conventional plastic part design to explain design considerations for manufacturing high-quality FDM parts.

Get specifics about design considerations for Fused Deposition Modeling by downloading our design guide.