.dxf file types / feature compatiblities

[maker9876]

I imported a .dxf file and the curves on the corners of a planar square (2d fillets) were not there: the square was square.

Are there compatibility issues with .dxf?

(This was apparently a .dxf produced by export from Illustrator. However I've heard other people can "see" the fillets.)

[HughesTooling · Accepted solution]

It should work for an arc, the only curve typre I've seen problems with are splines. I seem to remember if you have a poly curve it doesn't import correctly, if you explode into lines and curves the import works.

Mark

[maker9876]

Thanks.

Reading around the subject there does seem to be something going on there.

In an adobe forum I found "what you need to do in Illustrator is use the Object»Path»Simplify menu item, and then check the "Straight Lines" option. You may need to use the "Object»Paths»Add Anchor Points" menu item a few times before simplifying to straight lines gives you enough detail."

All I can say is that this definitely worth a feature request: "proper support for importing various forms of curve in .dxf files."

I'm sure that's somewhere in the Autodesk codebase!

[HughesTooling]

Can you attach one of the DXF files that doesn't import, I'm just curious to see what's causing the problem.

Thanks Mark

[maker9876]

Sure. I have to wait a couple of days before this design is officially "open source" (it's not mine) and then I'll post. Thanks for taking an interest.

[Anonymous]

What is described by the OP is a very common problem with DXF import in many CAD systems.  It seems the DXF spec is not only subject to interpretation, so different applications interpret it in different ways, but also changes often, so there are about a billion different versions of DXF.  The result is DXF import is a nightmare.  This has been my experience with every CAD program I've ever used that supported DXF/DWG import.  Some features disappear entirely, others get mis-converted, often in very bizarre ways.

Regards,

Ray L.

[maker9876]

Here we are, two files.

The JPEG shows how the central rectangle should look.

The DXF looks different (square corners) when imported in Fusion360.

DXF (for lasercutting) was an export from Adobe Illustrator and is a part of this distribution: http://www.thingiverse.com/thing:1521722

[HughesTooling]

I've opened your file in 3 other programs and they all show a sharp corner, have you tried reimporting into the program it came from.

Rhino

Mark

[maker9876]

Interesting.

The creator of the file assures me that some people have had luck with it.

It was created with Adobe Illustrator. I'll communicate your suggestion and let you know if we discover anything.

Thanks.

[maker9876]

Well, the solution found was as follows. The file creator says (in Adobe Illustrator) "I clicked 'expanded appearance' on all the vectors. Then i exported the DXF and changed the option from 'Maximum Editability' to 'Preserve Appearance'."

It appears to have had the desired effect and the .dxf now compares favourably to the .jpeg.

Have learnt to be careful with dxf. Thanks again.