diff --git a/src/Mod/Fem/Gui/ViewProviderFemMesh.cpp b/src/Mod/Fem/Gui/ViewProviderFemMesh.cpp
index c9eb91137..36d684959 100644
--- a/src/Mod/Fem/Gui/ViewProviderFemMesh.cpp
+++ b/src/Mod/Fem/Gui/ViewProviderFemMesh.cpp
@@ -1136,6 +1136,7 @@ void ViewProviderFEMMeshBuilder::createMesh(const App::Property* prop,
                     break;
                 // 4 nodes
                 case 4:
+                    // tetra4 volume, four 3-node triangles
                     Base::Console().Log("    %f: Start build up triangle vector for 4 nodes object\n",Base::TimeInfo::diffTimeF(Start,Base::TimeInfo()));
                     Base::Console().Log("    NumNodes:%i\n",facesHelper[l].Element->NbNodes());
                     switch (facesHelper[l].FaceNo){
@@ -1161,58 +1162,58 @@ void ViewProviderFEMMeshBuilder::createMesh(const App::Property* prop,
                             insEdgeVec(EdgeMap, nIdx3, nIdx0);
                             vFaceElementIdx[indexIdx++] = ElemFold(facesHelper[l].ElementNumber, 0);
                             break;    }
-                        case 1: { // tetra4 volume: face 1
+                        case 1: { // tetra4 volume: face 1, 3-node triangle
                             Base::Console().Log("    %f: Start build up triangle vector for tetra4 --> face1\n",Base::TimeInfo::diffTimeF(Start,Base::TimeInfo()));
                             Base::Console().Log("    FaceNo:%i\n",facesHelper[l].FaceNo);
                             int nIdx0 = mapNodeIndex[facesHelper[l].Element->GetNode(0)];
                             int nIdx1 = mapNodeIndex[facesHelper[l].Element->GetNode(1)];
                             int nIdx2 = mapNodeIndex[facesHelper[l].Element->GetNode(2)];
-                            indices[index++] = nIdx2;
                             indices[index++] = nIdx0;
                             indices[index++] = nIdx1;
+                            indices[index++] = nIdx2;
                             indices[index++] = SO_END_FACE_INDEX;
                             insEdgeVec(EdgeMap,nIdx0,nIdx1);
-                            insEdgeVec(EdgeMap,nIdx0,nIdx2);
                             insEdgeVec(EdgeMap,nIdx1,nIdx2);
+                            insEdgeVec(EdgeMap,nIdx2,nIdx0);
                             vFaceElementIdx[indexIdx++] = ElemFold(facesHelper[l].ElementNumber,0);
                             break;    }
-                        case 2: { // tetra4 volume: face 2
+                        case 2: { // tetra4 volume: face 2, 3-node triangle
                             int nIdx0 = mapNodeIndex[facesHelper[l].Element->GetNode(0)];
-                            int nIdx1 = mapNodeIndex[facesHelper[l].Element->GetNode(1)];
-                            int nIdx3 = mapNodeIndex[facesHelper[l].Element->GetNode(3)];
-                            indices[index++] = nIdx1;
+                            int nIdx1 = mapNodeIndex[facesHelper[l].Element->GetNode(3)];
+                            int nIdx2 = mapNodeIndex[facesHelper[l].Element->GetNode(1)];
                             indices[index++] = nIdx0;
-                            indices[index++] = nIdx3;
+                            indices[index++] = nIdx1;
+                            indices[index++] = nIdx2;
                             indices[index++] = SO_END_FACE_INDEX;
                             insEdgeVec(EdgeMap,nIdx0,nIdx1);
-                            insEdgeVec(EdgeMap,nIdx0,nIdx3);
-                            insEdgeVec(EdgeMap,nIdx1,nIdx3);
+                            insEdgeVec(EdgeMap,nIdx1,nIdx2);
+                            insEdgeVec(EdgeMap,nIdx2,nIdx0);
                             vFaceElementIdx[indexIdx++] = ElemFold(facesHelper[l].ElementNumber,1);
                             break;    }
-                        case 3: { // tetra4 volume: face 3
-                            int nIdx1 = mapNodeIndex[facesHelper[l].Element->GetNode(1)];
+                        case 3: { // tetra4 volume: face 3, 3-node triangle
+                            int nIdx0 = mapNodeIndex[facesHelper[l].Element->GetNode(1)];
+                            int nIdx1 = mapNodeIndex[facesHelper[l].Element->GetNode(3)];
                             int nIdx2 = mapNodeIndex[facesHelper[l].Element->GetNode(2)];
-                            int nIdx3 = mapNodeIndex[facesHelper[l].Element->GetNode(3)];
-                            indices[index++] = nIdx2;
+                            indices[index++] = nIdx0;
                             indices[index++] = nIdx1;
-                            indices[index++] = nIdx3;
+                            indices[index++] = nIdx2;
                             indices[index++] = SO_END_FACE_INDEX;
+                            insEdgeVec(EdgeMap,nIdx0,nIdx1);
                             insEdgeVec(EdgeMap,nIdx1,nIdx2);
-                            insEdgeVec(EdgeMap,nIdx1,nIdx3);
-                            insEdgeVec(EdgeMap,nIdx2,nIdx3);
+                            insEdgeVec(EdgeMap,nIdx2,nIdx0);
                             vFaceElementIdx[indexIdx++] = ElemFold(facesHelper[l].ElementNumber,2);
                             break;    }
-                        case 4: { // tetra4 volume: face 4
-                            int nIdx0 = mapNodeIndex[facesHelper[l].Element->GetNode(0)];
-                            int nIdx2 = mapNodeIndex[facesHelper[l].Element->GetNode(2)];
-                            int nIdx3 = mapNodeIndex[facesHelper[l].Element->GetNode(3)];
-                            indices[index++] = nIdx3;
+                        case 4: { // tetra4 volume: face 4, 3-node triangle
+                            int nIdx0 = mapNodeIndex[facesHelper[l].Element->GetNode(2)];
+                            int nIdx1 = mapNodeIndex[facesHelper[l].Element->GetNode(3)];
+                            int nIdx2 = mapNodeIndex[facesHelper[l].Element->GetNode(0)];
                             indices[index++] = nIdx0;
+                            indices[index++] = nIdx1;
                             indices[index++] = nIdx2;
                             indices[index++] = SO_END_FACE_INDEX;
-                            insEdgeVec(EdgeMap,nIdx0,nIdx2);
-                            insEdgeVec(EdgeMap,nIdx0,nIdx3);
-                            insEdgeVec(EdgeMap,nIdx3,nIdx2);
+                            insEdgeVec(EdgeMap,nIdx0,nIdx1);
+                            insEdgeVec(EdgeMap,nIdx1,nIdx2);
+                            insEdgeVec(EdgeMap,nIdx2,nIdx0);
                             vFaceElementIdx[indexIdx++] = ElemFold(facesHelper[l].ElementNumber,3);
                             break;    }
                         default: assert(0);