Loss of model geometry upon import

Bug Reports
1

Hi,

I’m going through tutorials for a different FEA software with the supplied cad files. I convert the files to .step and import it into PrePoMax and try to replicate the example.

I’m doing a simple frequency analysis on a tuning fork, but the .step file seems to lose the ball at the end of the tuning fork upon import into PrePoMax. The below photos show the geometry when it’s .step format in CAD program (OnShape), and the other one shows after import in prepomax.

I’m happy to provide any further info if needed.

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image1755×910 136 KB

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image1714×845 65.5 KB

2

Try importing this .step file obtained from conversion to other software, like FreeCAD.

1 Like
3

Is it possible that you share the .step file?

4

Certainly.

5

When I import that STEP model to FreeCAD, it also lacks that ball at the end:

fork freecad
fork freecad1032×538 44.7 KB

So it’s not a fault of PrePoMax but rather some issue with converting formats in other software.

6

Ah, that’s great to know! Thanks for checking my model. Sorry for causing this silly post then :slight_smile:

7

I have tested the file in Solidworks, and the model is opened with the sphere at the end of the fork. PrePoMax uses Open cascade as a CAD library and the same library is used by Free CAD and Salome and Netgen, as far as I know, so the results in Open cascade are likely the same. But this is weird since all other models we and our students tried had no missing geometry. And we tested plenty.

8

I will close this bug report since it is not a PrePoMax bug.