Abstract: A method of printing a multi-material part in a layer-wise manner with an extrusion-based 3D printer includes providing a sliced digital model of a multi-material part and determining a number of materials in each of the slices of the digital mode. The method includes utilizing a digital model of a purge tower having N subdivisions having a closed geometry, wherein N is the number of print heads needed to print the part that is greater than or equal to three, each adjacent subdivision contact one another along an interface and assigning each print head to one subdivision and to tool paths forming the one subdivision in each layer. The method includes reassigning the assigned subdivision within the purge tower of an inactive print head in a layer to a print head that is active in the layer of the multi-material part.

Abstract: A three-dimensional part is printed using an additive manufacturing technique. The three-dimensional part includes an outer wall having an outer surface defining a shape of a part and in interior surface defining an interior cavity. The part includes a plurality of first sections having a plurality of printed layers, each printed layer of the first section having a plurality of wall segments that form triangle shaped cells wherein each of the plurality of first sections are attached to the interior surface of the outer wall.

Abstract: A three-dimensional part is printed using an additive manufacturing technique. The three-dimensional part includes an outer wall having an outer surface defining a shape of a part and in interior surface defining an interior cavity. The part includes a plurality of first sections having a plurality of printed layers, each printed layer of the first section having a plurality of wall segments that form triangle shaped cells wherein each of the plurality of first sections are attached to the interior surface of the outer wall.