Creating constructions lines in cylindrical faces  bolt abstraction
Bolts can sometimes be modeled as simple line bodies. With construction lines, we can easily achieve this. Yet, how can we automate the creation of line bodies from a number of selected cylindrical faces?
Answers

Hi @Pierre Thieffry This doesn't appear to be a question? Would you be able to edit it into the standard Question/Answer format? Thanks!
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The script below shows a sample implementation: the user needs to select all cylindrical faces to use as a basis for line creation. Then we create one construction line per face and create the corresponding line body in the geometry. It uses the fact that the drawing plane for the construction line can be snapped to a cylindrical surface  Mechanical will automatically propose a plane along the axis of the face.
Couple limitations of this example:
it is assumed the main axis of the cylindrical face is parallel to the global Y axis.
one construction line per face, we could replace by a single line for all faces
the 'Construction Geometry' folder must exist in the project (2021R1)
Additional notes: the construction lines will follow geometric changes (for example if you move the cylindrical faces). However, the corresponding line bodies under geometries will not be updated until you click on "Update Geometry" for EACH body. The update can of course be scripted in a few lines (see bottom of the post)
curSel=ExtAPI.SelectionManager.CurrentSelection construction_geometry = Model.ConstructionGeometry for faceId in curSel.Ids: print faceId face=ExtAPI.DataModel.GeoData.GeoEntityById(faceId) mid0=face.Centroid mid1=face.Edges[0].Centroid mid2=face.Edges[1].Centroid construction_line = construction_geometry.AddConstructionLine() plane= construction_line.CreatePlane(DataModel.GeoData.GeoEntityById(faceId)) [plane_1] = ConstructionLineHelper.GetPlanesById(construction_line, [1]) y1=mid1[1]mid0[1] y2=mid2[1]mid0[1] [point2d_planar_1, point2d_planar_2] = construction_line.CreatePlanarPoints(plane_1, [(0,y1), (0.0,y2)]) edge_collection_4 = construction_line.CreateStraightLines([point2d_planar_1, point2d_planar_2], [(0, 1)]) with Transaction(): construction_line.AddToGeometry() #endregion #Update geometry for all construction lines constructionLines=ExtAPI.DataModel.GetObjectsByType(Ansys.ACT.Automation.Mechanical.ConstructionLines.ConstructionLine) with Transaction(): for constLine in constructionLines: constLine.UpdateGeometry()
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