Infill in FDM Printing
Infill defines the internal pattern and density created between the outer shells of an FDM part.
Definition
Infill is the internal lattice between an FDM part's outer walls and top and bottom layers. Its percentage describes the approximate filled volume, while its pattern changes how loads travel through the interior. One hundred percent infill is not automatically the strongest or most economical choice.
Related Terms
- FDM: the process in which infill is defined during slicing.
- PLA: a filament commonly printed at different infill levels for prototypes.
- DFM: the practice of evaluating walls, orientation, infill, and load path together.
- STL: a mesh format that carries the external surface geometry, not the infill.
Common Uses
Low percentages save time and material in visual prototypes. Medium percentages are common for housings and fixtures. Higher values can help around connections or under compression, but strength often depends more on wall count, print orientation, and local geometry.
Watchouts
Instead of supplying only a percentage in the RFQ, explain where and how the part will be loaded. Screws, inserts, and joints may need extra walls or local solid regions. The Creator should recommend material, pattern, wall count, and orientation together.