Hi All,
I think my explanations need to be clarified, as I may have miss-interpreted the request.
In order to drive a machine in Fusion several elements may be needed.
To generate the g-code a post processor is mandatory. (it’s a file with a .cps extension)
Then if the machine is a multi-axes machine (milling with more than 3 axis) then a kinematic definition must be provided. The machine definition is a .mch file if there is only the kinematic chain definition, and it’s a f3d (or f3dz) file when containing a 3d machine simulation.
Posts are stored in the post library, and the mch are stored in the machine library. F3d must be moved into a personal folder on the cloud or locally, then imported into the library.
In older posts, before the global restructuring we have done last year, the kinematic definition was previously handled in different ways.
Using post properties to select an existing kinematic (smoothie.cps using "Fourth axis mounted along" property),
Using a hardcoded kinematic inside a machine specific post (deprecated post dmg mori dmu 60.cps)....
Nowadays we prefer to use a machine definition file, stored in the machine library. This machine definition file may or not contain a solid model for 3D simulation. The 3d model can be identified by the isometric cube icon.

So, when importing a post in the post library, it's only importing the post.
If the machine is more than 3 axes, then a machine definition file may be used or created to define the kinematic chain. We are only providing machine definition for manufacturers who signed an agreement with Autodesk.
We do not use the 3d models, without their consents, because of intellectual property restriction.
We have not signed approval with all manufacturers.
We plan to later add some machine definition files without cad model, defining only the kinematics, using the information’s collected previously for another software. But the data need to be converted between the formats.
So, Autodesk have not created, as of now, any machine definition for the Laguna brand. If you need a machine definition for a multi axis machine, you can take a look at:
https://help.autodesk.com/view/fusion360/ENU/?guid=MFG-MACHINES
to learn more about it.
To recap, a machine is not absolutely needed for milling in 3 axes but is absolutely needed with the most recent post for multiaxis machine. It can support machine simulation, but it's not a requirement, only the kinematic definition is critical.
When creating a NC program, a post MUST be selected, and a machine definition MIGHT be required if the toolpath is multi axes.
If the machine had been associated into the setup, it will automatically selected when creating the NC program.
Let's hope it will bring more clarity.
Regards
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