diff --git a/libsrc/csg/algprim.cpp b/libsrc/csg/algprim.cpp
index c324e460..0f870d98 100644
--- a/libsrc/csg/algprim.cpp
+++ b/libsrc/csg/algprim.cpp
@@ -1236,7 +1236,15 @@ namespace netgen
     return max2(bb/(aa*aa),aa/(bb*bb));
   }
 
+  int EllipticCylinder :: IsIdentic(const Surface& s2, int& inv, double eps) const
+  {
+    const EllipticCylinder* ps2 = dynamic_cast<const EllipticCylinder*>(&s2);
+    if (!ps2) return 0;
 
+    if((vl - ps2->vl).Length() > eps || (vs - ps2->vs).Length() > eps || (a-ps2->a).Length() > eps)
+      return 0;
+    return 1;
+  }
 
   Point<3> EllipticCylinder :: GetSurfacePoint () const
   {
diff --git a/libsrc/csg/algprim.hpp b/libsrc/csg/algprim.hpp
index ab496cc7..6daf643b 100644
--- a/libsrc/csg/algprim.hpp
+++ b/libsrc/csg/algprim.hpp
@@ -303,7 +303,8 @@ namespace netgen
 					   const Box<3> & bbox, 
 					   double facets) const;
 
-  
+    virtual int IsIdentic (const Surface & s2, int & inv, double eps) const;
+
     virtual double MaxCurvature () const;
 
     virtual double MaxCurvatureLoc (const Point<3> & /* c */ , 
diff --git a/libsrc/csg/python_csg.cpp b/libsrc/csg/python_csg.cpp
index 74067f23..0db96e6d 100644
--- a/libsrc/csg/python_csg.cpp
+++ b/libsrc/csg/python_csg.cpp
@@ -235,13 +235,17 @@ DLL_HEADER void ExportCSG(py::module &m)
 	    return self.GetNP()-1;
 	  }),
 	 py::arg("x"),py::arg("y"),py::arg("z"),py::arg("hpref")=false)
-    .def("AddSegment", FunctionPointer
-	 ([] (SplineSurface & self, int i1, int i2, string bcname, double maxh)
+    .def("AddSegment", [] (SplineSurface & self, int i1, int i2, string bcname, double maxh)
 	  {
             auto seg = make_shared<LineSeg<3>>(self.GetPoint(i1),self.GetPoint(i2));
 	    self.AppendSegment(seg,bcname,maxh);
-	  }),
+	  },
 	 py::arg("pnt1"),py::arg("pnt2"),py::arg("bcname")="default", py::arg("maxh")=-1.)
+    .def("AddSegment", [] (SplineSurface& self, int i1, int i2, int i3, string bcname, double maxh)
+         {
+           auto seg = make_shared<SplineSeg3<3>>(self.GetPoint(i1), self.GetPoint(i2), self.GetPoint(i3));
+           self.AppendSegment(seg, bcname, maxh);
+         }, py::arg("pnt1"),py::arg("pnt2"), py::arg("pnt3"),py::arg("bcname")="default", py::arg("maxh")=-1.)
     ;
   
   py::class_<SPSolid, shared_ptr<SPSolid>> (m, "Solid")
@@ -455,7 +459,12 @@ However, when r = 0, the top part becomes a point(tip) and meshing fails!
 	    self.GetTopLevelObject(tlonr) -> SetBCProp(surf->GetBase()->GetBCProperty());
 	    self.GetTopLevelObject(tlonr) -> SetBCName(surf->GetBase()->GetBCName());
 	    self.GetTopLevelObject(tlonr) -> SetMaxH(surf->GetBase()->GetMaxH());
-	    for(auto p : surf->GetPoints())
+            Array<Point<3>> non_midpoints;
+            for(auto spline : surf->GetSplines())
+              {
+                non_midpoints.Append(spline->GetPoint(0));
+              }
+	    for(auto p : non_midpoints)
 		self.AddUserPoint(p);
             self.AddSplineSurface(surf);
 	  }),
diff --git a/libsrc/csg/splinesurface.cpp b/libsrc/csg/splinesurface.cpp
index 986d616e..6134b1f4 100644
--- a/libsrc/csg/splinesurface.cpp
+++ b/libsrc/csg/splinesurface.cpp
@@ -62,7 +62,30 @@ void SplineSurface :: AppendPoint(const Point<3> & p, const double reffac, const
             cuttings->Append(plane);
           }
         else
-          throw NgException("Spline type not implemented for SplineSurface!");
+          {
+            auto spline3 = dynamic_cast<SplineSeg3<3>*>(spline.get());
+            if(spline3)
+              {
+                auto p1 = Point<3>(spline3->StartPI());
+                Project(p1);
+                auto p2 = Point<3>(spline3->TangentPoint());
+                Project(p2);
+                auto p3 = Point<3>(spline3->EndPI());
+                Project(p3);
+                Vec<3> v1 = p2-p1;
+                Vec<3> v2 = p2-p3;
+                Point<3> mid = p1 - v2;
+                cout << "mid point = " << mid << endl;
+                cout << "v1 = " << v1 << endl;
+                cout << "v2 = " << v2 << endl;
+                auto cyl = make_shared<EllipticCylinder>(mid, v1, v2);
+                if(maxh[i] > 0)
+                  cyl->SetMaxH(maxh[i]);
+                cuttings->Append(cyl);
+              }
+            else
+              throw NgException("Spline type not implemented for SplineSurface!");
+          }
       }
     all_cuts = cuttings;
     return cuttings;
diff --git a/libsrc/geom2d/python_geom2d.cpp b/libsrc/geom2d/python_geom2d.cpp
index 1ba68b20..a16c13f7 100644
--- a/libsrc/geom2d/python_geom2d.cpp
+++ b/libsrc/geom2d/python_geom2d.cpp
@@ -17,7 +17,8 @@ DLL_HEADER void ExportGeom2d(py::module &m)
 {
   py::class_<SplineGeometry2d, NetgenGeometry, shared_ptr<SplineGeometry2d>>
     (m, "SplineGeometry",
-     "a 2d boundary representation geometry model by lines and splines")
+     "a 2d boundary representation geometry model by lines and splines",
+     py::multiple_inheritance())
     .def(py::init<>())
     .def(py::init([](const string& filename)
                   {