Assembly4: Modelling In-Context

Mods Assembly
1

This is an example of how to model in-context or “top-down” using Assembly4. The assembly is based on a design found here: https://www.youtube.com/watch?v=zU1F-RnprBU which I think serves as a good comparison between FreeCAD and Solidworks capabilities.

There seems to be some confusion of new users and lots of questions about how to best attach and locate the universal LCS connectors that Assembly4 uses as joints. The method presented here is based on the default LCS that is included in the Assembly4 body. This approach simplifies the assembly design process and facilitates in-context modelling which I prefer for designing assemblies. In the captions of the following images I will try to describe in detail the steps used to model each part in the context of the assembly, assemble the bodies, set LCS joint constraints and limits, and animate each degree of freedom the design requires. It is assumed that you are comfortable with PartDesign and the Assembly4 process.

punch0.jpg
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punch1.jpg
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punch2a.jpg
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punch2b.jpg
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punch3.jpg
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I will be adding more details of the modelling process in additional posts as time allows. Questions or comments are welcome.

OS: Windows 11 build 22621
Word size of FreeCAD: 64-bit
Version: 0.22.0dev.35639 (Git)
Build type: Release
Branch: main
Hash: f315314569aee5334fd0e69a49aab33684a802ba
Python 3.10.13, Qt 5.15.8, Coin 4.0.2, Vtk 9.2.6, OCC 7.6.3
Locale: English/United States (en_US)
Installed mods:

  • Assembly4 0.50.6
  • fasteners 0.5.0
  • freecad.gears 1.2.0
  • QuickMeasure 2022.10.28
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And, the saga continues:
punch4.jpg
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punch5.jpg
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punch8.jpg
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punch9.jpg
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punch10.jpg

3

One more time:
punch11.jpg
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punch11b.jpg
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punch12a.jpg
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punch12b.jpg
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Hopefully, by now, you are getting the basic idea of how this process works and that my brief descriptions are helpful. Try it you might like it.

4

For the sake of completeness I include here the rest of the assembly constraints:

punch13.jpg
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punch14.jpg
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punch15.jpg
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punch16.jpg
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punch17.jpg
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This completes my brief overview of a moderately complex example of modelling in-context using the Assembly4 mechanical design workbench which can be directly compared to SolidWorks. Hopefully, it has been of some use for new users making the transition. If anyone is interested in the file please PM me for a temporary Dropbox link. It is too large to attach, 2.33 Mb with screw threads, 1.22 Mb without.