Unwrap and SVG exporting problem of 3d surfaces

[emirudlari]

Hi,  I have some 3d surface (pic. 1). To produce them I want to unwrap and cut them from a piece of thin wood plate with laser or router. Then I will bend them again on a mold. So I need to unwrapped boundary paths. For this, I designed these surface on Fusion 360, then export as a STL. I unwrapped some of them but one surface wasn't unwrapped normally (pic. 2).  Then I used "generate face groups" option and after that, I could unwrap. But now, I am not sure whether the unwrapped model is true. Secondly, I couldn't export any model as a SVG format. Always give an error. I attached STL files. Thank you, Best. 

Emir.

[Anonymous · Accepted solution]

Sorry, the STL you wanted to attach is missing. Think you need to zip it?

The image of the unwrap result looks odd. But it's hard to give advice without the STL.

About your export .svg issue: There's a non Latin char "Ç" in your path. Maybe this causes the trouble? 

[emirudlari]

First of all, I changed the folder directory of exporting SVG with not including Latin character and exporting works, thank you. Secondly, I added STL files with the zipped version. 

[Anonymous · Accepted solution]

Interesting: Seems Unwrap is sensible to zero-area faces (or almost zero-area too?):

Importing, combining and running CloseCracks on normal2 (white) and problem (pale orange) I checked the boundary between. Right there where bending happens are triangle vertices at the seam on problem which are not used by normal2 (selected here):

As CloseCracks didn't leave open boundaries there, this means there have to be invisible, non area triangles on one of the source meshes (e.g. There is a non visible triangle A>B>C).

As the bending of Unwrap happens there where your source application added these faces, I think that Unwrap doesn't handle such cases properly.

Now to fix this issue:

I imported all files and combined them to one (to speed up the workflow I combined them to one but didn't run EDIT CloseCracks. Of course you can do the same for each object separately). 

SelectAll and run Edit/Remesh (default value settings are OK here) and set BoundaryMode to RefinedBoundary.

Accept and run Unwrap:

Think this should be a standard procedure after we found this issue. This might happen on more complex unwrapping too but be not that evidently as in your case. Thanks

[emirudlari]

Thank you very much Magweb, it really solved my problem.

Secondly, after solving unwrap issue and SVG export problem,  I noticed that when I import SVG files to fusion 360, dimensions are changed. I read forums about this issue but no one says about Meshmixer export SVG setting. Best.

 

[Anonymous]

Did you try to use InkscapeSVG instead of IllustratorSVG in the ExportSVG dialog?

Seems InkscapeSVG defines the units(mm) while IllustratorSVG doesn't and two such versions of the same unwrap appear (in another soft I use) in different sizes. 

[emirudlari]

I tried both of them and two methods gave diferent results. And I drew a 100x100 rectangular in fusion 360, then sent it to meshmixer and exported by using illustrator and inkscape options. I found the ratio between orginal and imported SVG files. I think I can use 1.33333 scale value with illustrator SVG option, 

 

[Anonymous]

Look into Fusion360 forum threads. There are reports that this 1.33 ratio upscaling needs to be done even if the .svg comes from Adobe Illustrator directly. 

Think that's an Fusion360 import issue and not related to MM's export.