Hello,
Can you give a try at the attached file.
If you double-click the spiral object in the tree-view, it should enter edit-mode.
This doesn't always work, as it depends on the version of the coin library of FreeCAD.
If it works, instructions are displayed in the report view.

Part->Offset2D works.
Draft->Offset doesn't.

The problem is not the BSplines.
The shape in the test file is a compound of individual edges, it is not a wire.
You need to Draft->Upgrade it to a wire.

Great

A test file would help. Maybe you can switch to Surface workbench, use this joincurve as the boundary curve for a Filling surface, and add some vertex constraints inside the surface. Or you can also try to generate a point-cloud object from the surface mesh and use the Reverse Engineering WB to appr...

Hard to tell without a test file. First, you can test if your wire is valid : wire = Part.Wire([bs2.toShape(), bs3.toShape(),.......,edge.Edges]) print("Valid wire : %s"%str(wire.isValid())) print("Closed wire : %s"%str(wire.isClosed())) disc_t = Part.Face(wire) print("Valid face : %s"%str(disc_t.is...

Hi,glad to see u again!I'm confused how to do these three steps with python code?Do you have any simple code examples for these three steps?Looking forward to your reply!Thanks! Don't use this, it is outdated. Use the Gordon surface. I already answered about the Gordon surface scripting : import go...

This sketch give a BOPAlgo GeomAbs_C0 error through a JoinCurve. That carry out this error with any surface. Any suggestion? I don't know the reason for the C0 continuity. I can get C1, but only with very high tolerance setting. In this case, I would suggest to discretize (set Target to "Wire" ) an...

I would do :

Still a mystery to me as to why it requires a double reference I suppose that this property gets a special treatment internally : - when it is set to a list of strings, the enum gets populated - when it is set to an integer, the index in the EXISTING enum is set ['rad','deg'].index(aunit) # This is...