Design Engine
Tools and Features

Combine

8min

Combine merges separate parts (individual STL mesh files) into one mesh file for printing.

It is recommended to use this feature after you have applied all other optional features.

Benefits of Combine

Some applications may benefit from a partial lattice, while still being printed as one part. Examples include:

  • Lightweighting to reduce the overall mass of a part
  • Skins to provide a covering, or "upholstery", to a cushion lattice
  • Flat surface to apply part labels
  • Functional lattices such as COVID testing swabs


Combine Workflow

1

Create CAD models

Create the model(s) to be merged as separate part(s) in the CAD file.

In this example, the wrist pad will be latticed and a small label will be combined as one part.

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2

Combine in Design Engine



Are your parts not aligning correctly upon import? Make sure you export parts from an assembly so that all parts use the same coordinates. Reference the Lattice File Preparation - File Export lesson for details.

Skins on a Lattice

Skins are often useful over an elastomeric lattice when you want the performance of a lattice but need a smooth surface in some areas for functional reasons.

Design Guidelines for Skins

  • 0.7 - 1.0 mm thickness recommended for skins
  • Position the skin proud of the lattice surface by at least 1/2 the strut diameter to achieve a smooth surface (lattices generate outwards by 1/2 the strut diameter)
Positioning of skin in CAD
Positioning of skin in CAD

Skin proud of lattice design space by 1/2 strut diameter + 0.1 mm
Skin proud of lattice design space by 1/2 strut diameter + 0.1 mm

Skin surface flush with lattice design space surface
Skin surface flush with lattice design space surface


Note that skins should overlap with the lattice struts to properly combine. Do not place the skin flush with the edge of the strut.

Note that any lines you see in the software where the lattice intersects is a rendering anomaly - zooming in closer will remove the anomaly.

Drainage

Always provide drainage holes for liquid resin when a skin or housing shell provides near or full coverage of the lattice.

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Liquid resin needs to have drainage both during printing and post-processing.

  • 2.5 mm diameter
  • Provide as many holes as the design allows
  • Avoid placing holes directly over a strut or utilize a consistent pattern for hole placement

Combine is Not a Boolean Union Operation