cannot cut into a linked assembly

[d_hg]

Hola -

I designed a generic rack-mount enclosure, and now I want to use it as the base model for a few variations with different panel cutouts. The process I've tried:

• make a new design file
• insert the generic enclosure in as a linked assembly
• draw a sketch with the panel cutout shapes
• try to extrude cut into the linked panel component

Trying to do this gives "Error: No target body found to cut or intersect!"

A couple other things I've noticed

• There is no issue cutting through components that were made in the new linking model
• Trying to break the link with the base model gives "Error: Break link fails due to cycle link or other reason!"

Any help is appreciated!

[jeff_strater]

Yes, @d_hg, your observations are correct.

1. You cannot modify a referenced component from a feature at the top level.  That is partly design intent (we wanted to restrict potentially disruptive changes to a component in a larger team, by a referencing design.  It is also partly just an implementation limitation.  We don't have the software in place to do this.  We may implement this in the future.  This raises some questions, such as:  What to do if you have multiple instances of this component?  Are all affected?

2. This limitation does not exist for "local components".  Again correct.  Local components are local because they cannot be reused in other designs, so it seems logical that you can affect them with a local feature.

3. Break link fails.  If you can, we'd like to see this design.  This could be a bug, although there are cases where this error is legit.

The other thing to point out here is that you can always open the referenced design and make the change there.  I realize  that sometimes that is not practical or desired, but it is a way to get past this limitation.

Jeff Strater (Fusion development)

[d_hg]

Hey - thanks for the response, on a Sunday no less.

> You cannot modify a referenced component from a feature at the top level ... this limitation does not exist for "local components"

In fact I don't want the referenced component to be changed. This part of the reason why I tried moved to an external file: cutting into one instance of a local component was affecting all instances, which for my purpose was undesirable.

I'll try and explain what I'm trying to achieve. As an analogy: I'm looking for a behavior similar to "inheritance" in object-oriented programming, where a base class can be modified with variations to make subclasses. (The base class and subclasses can still have multiple instances which are essentially duplicates of each other.)

Here's the concrete example. I have a base class, which is this generic rack-mount enclosure:

Now I want to make some variations of this by defining panel cutouts. Two silly examples:

 

These subclasses share all the geometry defined in the base model (class) so any changes there propogate down to the subclasses. Conversely, changes to the subclasses do not propagate up to the base class.

> If you can, we'd like to see this design.

Sure, I'll send you the info.

thank you!

[d_hg]

Just FYI, this is how I originally expected things to work within a single file, given a sub-component (or sub-assembly) inside a parent assembly:

• with the sub-component activated, any cuts or modifications are made to all instances of that sub-component
• with the parent assembly activated, any cuts or modifications are made only to that one instance of the sub-component

This behavior would have allowed the parent assembly to behave like a  "subclass" as I described above.

[jeff_strater · Accepted solution]

Hi @d_hg,

Thanks for sharing the files, and the explanation of what you are trying to do.  Unfortunately, Fusion right now can't really do what you want, which is what we would call "design configurations".  In a product that supports this, you could derive different configurations (with different cutouts), and still maintain associative links to the "base configuration".  It's on our list, but honestly, don't hold your breath - this is a big project, and will likely be a ways out...

Another possibility, depending on what you want to do is what we would call "assembly features".  This is where you can make changes to a linked component, from the top level, and only affect one instance.  However, those are usually somewhat limited in what you can do, feature-wise.  And Fusion doesn't have that, either...

So, Break Link is one option, but as you said, that is causing problems on this model (we'll look into those).  Another approach would be to copy the design in the data panel, and make changes to the copy.

Jeff

[d_hg]

Okay, thanks for the explanation. I understand that F360 is a new product and even with these limitations it's miles ahead of Sketchup, which I was using previously.

I'm going to try projecting the outlines of the panels into a new sketch in the parent model, and re-modeling the panel, and hiding the child version. This should suffice for simple 2D panel cutouts, but won't help make cutouts in more complex forms.

One difficult aspect for me has been learning the relationship between concepts which seem very similar but have inconsistent behaviors. In particular: components, assemblies, and linked files all seem "the same" to me, differing only by nesting level and definition location.

I'm sure there are good and complex reasons for the current design, but it would be great if these (and any new variations like "design configurations") were merged into a single more consistent/unified paradigm. Relatedly, the "activate" functionality can be frustrating and surprising.

thanks for your help!