CAD model does not contain any assembly parts


#1

I tried to export a simple model from sketchup as stl and mesh it in SimScale. But the meshing returns the following error:

terminate called after throwing an instance of ‘std::runtime_error’
what(): CAD model does not contain any assembly parts

Does anybody have an idea?


#2

Hi @pi3141, are you able to share the project?

Cheers,
Darren


#3

Hi @pi3141,

Typically STL files are not very cooperative with the mesher as it requires a well defined solid geometry to mesh. However do share the project link first like Darren has mentioned so we can better identify the problem.

Cheers!

Regards,
Barry


#4

Sure, I’ve made the project public here: https://www.simscale.com/projects/pi3141/revit_test/

Just checked Revit. Same problem…


#5

Hi @pi3141,

Are you able to convert the original CAD model into another format like STEP, IGES or SolidWorks part file?

Cheers.

Regards,
Barry


#6

Unfortunately no. I’ve tried every converter and export type I could find by now


#7

Hi @pi3141!

Maybe @yosukegb4 can help out with Rhino here and see if there is any issue with your CAD.

Cheers!

Jousef


#8

Hi @pi3141,

Let me see if I can either fix the file or make it solid somehow. Get back to you asap.

Cheers.

Regards,
Barry


#9

Hi @pi3141,

Quick questions is the first and second geometry supposed to be that big? “sketchup” is over 200m across and duct_revit is over 2000m across.

Cheers.

Regards,
Barry

EDIT: I’ve converted the STL file to a solid file along with reducing the scale to something a little more realistic. It has meshed fine and you can see it under “mesh 3”.


#10

@Get_Barried thank you very much. That is awesome!

I guess the scaling problems are due to mm -> m conversions. Will be careful to scale them properly next time.

How did you fix the geometry? Just for me to know for next time. Can I do that myself?


#11

Hi @pi3141,

I wouldn’t consider it fixed as it is just simply a bunch of triangulated surfaces due to the STL file format. I recommend obtaining or re-drafting the original CAD file and converting it to IGES/STEP/SolidWorks part file instead. It would be more robust and easier to work it as well.

For this case I imported it into SolidWorks and selected the option that would turn the faces into solid surfaces. Then just simply upload it and you can see what you get. The mesher also tends to not like oversize geometries especially for STL so do take note of that.

Cheers!

Regards,
Barry