topic Re: How to fill geometry to create a solid body from an imported obj. file? in Fusion Design, Validate & Document Forum

How to fill geometry to create a solid body from an imported obj. file?

Anonymous — Tue, 23 Feb 2016 04:31:19 GMT

Hi,

I am importing mesh bodies from another program into fusion, performing mesh to brep operation, then creating a base form feature with them in order to edit the bodies. However, some of the bodies I import are not solid and I need them to be. I have played around trying to find a way to fill the geometry but cannot figure it out.

Can anyone give me instruction on how to 'fill in' an imported obj. body such as in my screen shot?

Also, in some of the more complex obj. files I am importing, when I perform a mesh to brep operation, instead of what I call a regular body being created, it creates a body type I do not know (see Screen Shot 2016-02-23 at 12.25.17 - under bodies named 'Body1 (8)'). Could anyone shed some light on what this is an what that means in terms of working with them? Ultimately, I am wanting to 3D print these objects so want to understand what kind of file these are.

Many thanks,

Cassandra

Re: How to fill geometry to create a solid body from an imported obj. file?

jeff_strater — Tue, 23 Feb 2016 15:11:23 GMT

Hi @Anonymous,

First, the body type in your first screen shot is a "surface body". A surface is a body that is not closed (think an inifinitely thin body). Usually surface bodies are used to build up a solid in the end (since you cannot really manufacture a surface).

Regarding filling in open areas, the two usual methods are Stitch and Boundary Fill. Stitch is used when working with surface bodies. For instance, if you make a cube out of 6 independent planar faces, using surface bodies, you can use Stitch to put it all together. If the result forms a closed region, then Stitch will produce a solid. The other method is Boundary Fill. This is a really useful tool that lets you do complex combinations of various surface and solid bodies. Here is a link to a helpful article on how to use it: Using Boundary Fill, and a quick review of the command: Boundary Fill Dialog.

In your case, Boundary Fill can be used to fill in the hollow areas in your model, with a combination of a Boundary Patch (surface body) to cover the holes, and using Boundary FIll to fill in the area with solid material.

Here is a quick screencast showing how to do this for a very simple case:

Hope this helps,

Jeff Strater (Fusion development)

Re: How to fill geometry to create a solid body from an imported obj. file?

James.Youmatz — Tue, 23 Feb 2016 15:17:09 GMT

Hi @Anonymous,

EDIT: Looks like @jeff_strater beat me to it! LOL

My apologies if this is obvious, but what screenshot is the body that needs to be filled in? There's definitely multiple ways to acheive this, so I am just trying to find the most efficient for your workflow! Most liley, the "fill" methods are going to be most effective after your conversion to a BRep from a mesh as this time Fusion does not have a built in mesh editing workspace (but soon though!). You can use booleans, boundary fill, patches, it really is dependent on what you are trying to do. If you want to share your model with me at james.youmatz@autodesk.com and give me a quick walkthrough on what you are trying to fill in, I would be more than happy to create a screencast showing I how go about it.

As for the unknown body types - those are patches. These are 2D surfaces with no thickness that, in your case, are created from your mesh conversion as it cannot stich all the surfaces together to create a quilt. Realistically what is happening is since there are gaps (none of the surfaces are touching), it assumes there are holes so it creates it in 2D surfacing so you can edit the holes and then "stich" them together to create a solid 3D body (or to manually add a thickness). Just note that you can do surface modeling whenever (the patch environment) it is not limited to mesh conversion.

Thanks,

Re: How to fill geometry to create a solid body from an imported obj. file?

Anonymous — Thu, 25 Feb 2016 11:35:42 GMT

Thanks a lot. I followed your instructions after viewing your video and it’s worked! Exactly what I was wanting to know!
Cheers!
Cassandra

Re: How to fill geometry to create a solid body from an imported obj. file?

Anonymous — Wed, 29 Mar 2017 17:54:02 GMT

Hi,

I had the same issue with an addition.

Imported a 3D scan (.stl) into meshmixer

Cleaned up the scan and turned it into a solid part

Exported it to a .obj at the 10k facets maximum.

Imported it into Fusion 360.

Followed the above steps and completed the boundary fill

Exported to a .stp file with hopes of importing it into Solidworks and finishing edits there. (I am just getting started with AD products)

When I tried to import the file I received a "no model thickness" error.

Despite the boundary fill, is there a reason my exports are still being read as surfaces?

Thanks

Re: How to fill geometry to create a solid body from an imported obj. file?

TrippyLighting — Wed, 29 Mar 2017 22:41:43 GMT

You should probably create your own thread and share the source files so we can reproduce the steps.

A .stl file requires a different workflow than an imported .obj file with nice quad faces.

Re: How to fill geometry to create a solid body from an imported obj. file?

13901182494 — Tue, 03 Oct 2017 11:32:43 GMT

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