# How to work on geometry before doing meshing? **URL:** \ **Category:** General Questions\ **Created:** [August 11, 2022, 6:58am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353 "2022-08-11T06:58:33Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Mobis](https://avatars.discourse-cdn.com/v4/letter/m/ad7895/32.png) [@Mobis](https://prepomax.discourse.group/u/Mobis)\ **Post date:** [August 11, 2022, 6:58am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/1 "2022-08-11T06:58:33Z")
When i imported a .STP file, the whole geometry imported as a solid/shell part. If i want to select surface & do some work on surface like splitting the surface, toggle the line, taking trim…,it is not possible. Can anyone answer to this question ASAP? ---
**Author:** ![FEAnalyst](https://yyz2.discourse-cdn.com/free1/user_avatar/prepomax.discourse.group/feanalyst/32/688_2.png) [@FEAnalyst](https://prepomax.discourse.group/u/FEAnalyst)\ **Post date:** [August 11, 2022, 7:04am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/2 "2022-08-11T07:04:15Z")
Operations like this have to be performed in CAD software, before importing to PrePoMax since it features only basic tools for geometry modification, such as scaling and merging parts. ---
**Author:** ![Mobis](https://avatars.discourse-cdn.com/v4/letter/m/ad7895/32.png) [@Mobis](https://prepomax.discourse.group/u/Mobis)\ **Post date:** [August 11, 2022, 9:04am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/3 "2022-08-11T09:04:49Z")
Okay understood, but when i have given mesh parameters & creating mesh for some big complex geometries it is not creating mesh & also showing as failed meshing. May i know the reason? Ands also how to check 2d & 3d quality(like min.length, aspect ratio, skewness,tet-collapse) in prepomax after generating mesh? ---
**Author:** ![FEAnalyst](https://yyz2.discourse-cdn.com/free1/user_avatar/prepomax.discourse.group/feanalyst/32/688_2.png) [@FEAnalyst](https://prepomax.discourse.group/u/FEAnalyst)\ **Post date:** [August 11, 2022, 9:16am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/4 "2022-08-11T09:16:35Z")
Maybe the geometry is too complex and it should be simplified (defeatured) before importing to PrePoMax. You could also try decreasing the element size. Currently, PrePoMax doesn’t support mesh quality checks but some of them are available in Gmsh and Salome\_Meca (open-source meshers). Check this thread on CalculiX forum for more details: [Mesh Quality Check - CalculiX](https://calculix.discourse.group/t/mesh-quality-check/743) ---
**Author:** ![Mobis](https://avatars.discourse-cdn.com/v4/letter/m/ad7895/32.png) [@Mobis](https://prepomax.discourse.group/u/Mobis)\ **Post date:** [August 11, 2022, 9:21am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/5 "2022-08-11T09:21:59Z")
okay,Can you please suggest me some open-source CAE software’s which can perform following operations 1)Importing CATIA/STEP file 2)Able to work on geometry like defeaturing, splitting surfaces, toggle unnecessary lines 3)create good flow mesh 4)quality checking & remove bad quality 5)rigid ,material & property creation ---
**Author:** ![FEAnalyst](https://yyz2.discourse-cdn.com/free1/user_avatar/prepomax.discourse.group/feanalyst/32/688_2.png) [@FEAnalyst](https://prepomax.discourse.group/u/FEAnalyst)\ **Post date:** [August 11, 2022, 9:43am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/6 "2022-08-11T09:43:28Z")
It might be necessary (and better) to perform step 2 in FreeCAD and then import the prepared geometry to mesher such as Salome\_Meca. It’s not very intuitive but offers many options for mesh creation and verification. The last step can be done in PrePoMax. ---
**Author:** ![Mobis](https://avatars.discourse-cdn.com/v4/letter/m/ad7895/32.png) [@Mobis](https://prepomax.discourse.group/u/Mobis)\ **Post date:** [August 11, 2022, 9:47am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/7 "2022-08-11T09:47:40Z")
I have checked FreeCAD, but i am not able to perform those operations. Do you have any manual or link that can suggest how to perform those operations in FreeCAD? I already have a .step file, i just want to do defeature small fillets & unnecessary lines. ---
**Author:** ![FEAnalyst](https://yyz2.discourse-cdn.com/free1/user_avatar/prepomax.discourse.group/feanalyst/32/688_2.png) [@FEAnalyst](https://prepomax.discourse.group/u/FEAnalyst)\ **Post date:** [August 11, 2022, 10:02am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/8 "2022-08-11T10:02:45Z")
FreeCAD has Defeaturing tool in Part Workbench but there’s also whole Defeaturing Workbench available as add-on (can be easily downloaded from GitHub using Add-on Manager). If you want some recommendations regarding handling of your geometry in FreeCAD, ask on their forum. People there are very helpful and you will likely get response really quickly. When it comes to surface partitioning in FreeCAD, there are several boolean tools that can help with that but Boolean Fragments are best for surfaces. ---
**Author:** ![synt](https://yyz2.discourse-cdn.com/free1/user_avatar/prepomax.discourse.group/synt/32/4658_2.png) [@synt](https://prepomax.discourse.group/u/synt)\ **Post date:** [August 11, 2022, 10:07am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/9 "2022-08-11T10:07:05Z")
> [@Mobis](#): > > some open-source CAE software’s to do capable all the list you needed. it seems Salome CAD/CAE is the software what you’re looking for, as i know FreeCAD does not have mesh quality checking, or some updates may fullfiled. ---
**Author:** ![Mobis](https://avatars.discourse-cdn.com/v4/letter/m/ad7895/32.png) [@Mobis](https://prepomax.discourse.group/u/Mobis)\ **Post date:** [August 11, 2022, 10:08am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/10 "2022-08-11T10:08:32Z")
I will check Salome software for meshing, thanks for the reply ---
**Author:** ![Mobis](https://avatars.discourse-cdn.com/v4/letter/m/ad7895/32.png) [@Mobis](https://prepomax.discourse.group/u/Mobis)\ **Post date:** [August 11, 2022, 10:09am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/11 "2022-08-11T10:09:23Z")
I am checking FreeCAD software & posted my queries in their forum. Do you have complete understanding of operations that can be done in Prepomax? ---
**Author:** ![FEAnalyst](https://yyz2.discourse-cdn.com/free1/user_avatar/prepomax.discourse.group/feanalyst/32/688_2.png) [@FEAnalyst](https://prepomax.discourse.group/u/FEAnalyst)\ **Post date:** [August 11, 2022, 10:12am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/12 "2022-08-11T10:12:30Z")
Check the manual, all possible features are listed and described there so you can search for what you need: [Documentation – PrePoMax](https://prepomax.fs.um.si/documentation/) ---
**Author:** ![Mobis](https://avatars.discourse-cdn.com/v4/letter/m/ad7895/32.png) [@Mobis](https://prepomax.discourse.group/u/Mobis)\ **Post date:** [August 11, 2022, 10:21am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/13 "2022-08-11T10:21:19Z")
I have checked this documentation already Previously i have done a component(simple one) using prepomax & it created mesh But when i tried to mesh some other component it is not creating any mesh. I have checked with small to complex geometries too. and i want R-trias to be captured in some areas-for this there is no option available ---
**Author:** ![Mobis](https://avatars.discourse-cdn.com/v4/letter/m/ad7895/32.png) [@Mobis](https://prepomax.discourse.group/u/Mobis)\ **Post date:** [August 11, 2022, 10:22am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/14 "2022-08-11T10:22:51Z")
For meshing i want below operations to be done 1)Meshing with required mesh size 2)good flow 3)R-trias in specific areas 4)quality checking & removal 5)Can be work on elements ---
**Author:** ![synt](https://yyz2.discourse-cdn.com/free1/user_avatar/prepomax.discourse.group/synt/32/4658_2.png) [@synt](https://prepomax.discourse.group/u/synt)\ **Post date:** [August 11, 2022, 10:42am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/15 "2022-08-11T10:42:52Z")
but PrePoMax itself may enough to do the task, splitting surface also capable. regarding to mesh quality checking, Netgen mesher provide reliable and solvable almost. for shell element quality checking, is only for 2D classical check. since CalculiX expanded to 3D element (solid) so it does not required anymore. you can look at Matej video at YouTube, i do some comment also. [PrePoMax & CalculiX - A Preview of Shell Fuctionallity](https://www.youtube.com/watch?v=SbGDWqLxsy4) [PrePoMax & CalculiX - Shell features](https://www.youtube.com/watch?v=dUALkdr4f7w&t=211s) \*edited did you mean splitting a mesh (R-Tia) to make of two triangles from a quads? is mesh refinement feature is not capable. you may use Salome CAD/CAE if still needed. ---
**Author:** ![FEAnalyst](https://yyz2.discourse-cdn.com/free1/user_avatar/prepomax.discourse.group/feanalyst/32/688_2.png) [@FEAnalyst](https://prepomax.discourse.group/u/FEAnalyst)\ **Post date:** [August 11, 2022, 10:51am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/16 "2022-08-11T10:51:28Z")
> [@synt](#): > > splitting surface also capable Yes, but only with two points method so I suggested FreeCAD for more complex operations on geometry. After all, geometry handling is mainly a domain of CAD software and FEA preprocessors usually support only basic operations. ---
**Author:** ![Matej](https://avatars.discourse-cdn.com/v4/letter/m/a698b9/32.png) [@Matej](https://prepomax.discourse.group/u/Matej)\ **Post date:** [August 11, 2022, 11:28am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/17 "2022-08-11T11:28:54Z")
> [@Mobis](#): > > Okay understood, but when i have given mesh parameters & creating mesh for some big complex geometries it is not creating mesh & also showing as failed meshing. > May i know the reason? Mainly the mesh generation fails when the geometry of the part is “problematic”. That could be conversion/precision issues from one CAD software to the other; there could be tiny geometrical features in the geometry (check them using Geometry-Analyse) and there could be some inappropriate meshing parameters. So first check for tiny features and adjust the meshing parameters for the smallest element size. ---
**Author:** ![Mobis](https://avatars.discourse-cdn.com/v4/letter/m/ad7895/32.png) [@Mobis](https://prepomax.discourse.group/u/Mobis)\ **Post date:** [August 11, 2022, 11:47am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/18 "2022-08-11T11:47:10Z")
Yes, there are some small geometrical features in the geometry, may be because of that it is not generating mesh I am trying to remove those features in FreeCAD But how to adjust meshing parameters for the smallest element size? ---
**Author:** ![Matej](https://avatars.discourse-cdn.com/v4/letter/m/a698b9/32.png) [@Matej](https://prepomax.discourse.group/u/Matej)\ **Post date:** [August 12, 2022, 8:15am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/19 "2022-08-12T08:15:35Z")
You should use meshing parameters settings for a part: ![image](https://global.discourse-cdn.com/free1/uploads/prepomax/original/1X/9d35a570b3de9167906c924823bdc67bbfc70b81.png) ---
**Author:** ![Mobis](https://avatars.discourse-cdn.com/v4/letter/m/ad7895/32.png) [@Mobis](https://prepomax.discourse.group/u/Mobis)\ **Post date:** [August 22, 2022, 8:24am UTC](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353/20 "2022-08-22T08:24:50Z")
Yes I have used the same meshing parameters panel but my average mesh should be 2mm so i have used 2mm in max element size and the mesh is too fine in the fillets. Can u suggest meshing parameters to be set if i want uniform mesh size as 2mm throughout the geometry [Next page](https://prepomax.discourse.group/t/how-to-work-on-geometry-before-doing-meshing/353.md?page=2)