Since every now and then a new user of freecad is asking about the assembly workbench
I invested some time to gather the following information.
FreeCAD up to version 0.16.6703 for Linux/0.16.6704 for Windows/0.16.6705 for Mac OSX
Official assembly workbench
There was some initial work done on an assembly workbench.
The work is hosted here
It has to be compiled against a very old, now obsolete version of FreeCAD and is therefore
not recommended for use.
What do users do to get assemblies ?
There are several workarounds that could be used.
Just placing the solids in the correct position/orientation in 3D space
Using placement, draft move, draft rotate and alignment you can adjust the position/orientation
of the solids in 3D space.
With solids created in part workbench you can use those tools directly on the solid in question.
With solids created with the part design workbench you need to apply changes to
the first sketch used to create the solid in question.
As additional workaround some users like to create simple copies of the solids,
insert them in a new document and use the positioning tools on the simple-copy-solids.
Creating groups in the tree view can be used to organize your model better.
Creating the solids in place
Since placement, draft move and draft rotate could be used on solids and on sketches not attached to faces
you could use those methods to create your model already in correct position/orientation.
Use reorient sketch to detach sketches from faces.
Answering “yes” to the question about detaching the sketch and pressing “cancel” in the following menu
will just detach the sketch from its face.
Using spreadsheet workbench as assembly solver substitute
Since the spreadsheet workbench offers some functionality to read and control values and constraints
there may be cases when this could be used to “link” constraints in different sketches or the position
of different shapes and so getting some sort of solver controlled assembly.
Using workbench “assembly2”
User “Hamish” created a workbench allowing using constraints on solids.
The workbench is hosted here
Since User “Hamish” has announced stop providing support for his workbench discussion
has started on how the workbench could be used until an official assembly workbench
would be developed.
FreeCAD 0.17 (in development)
With this version a new internal data structure for the solids (especially for part design) was introduced.
The new workflow (called “part design next”) will not work with the current version of “assembly2”.
Since the author and maintainer of the workbench has announced stop providing support for his workbench
discussion has started on how the workbench could be used until an official assembly workbench
would be developed.
At the moment priority is to develop part design next and do the necessary bug-hunting and testing.
When part design next is in a releaseable state work may be continued on the official assembly workbench.