diff --git a/MatterControlLib/PartPreviewWindow/CreateDiscreteMeshes.cs b/MatterControlLib/PartPreviewWindow/CreateDiscreteMeshes.cs
index 3785d15a9..54b85a3e3 100644
--- a/MatterControlLib/PartPreviewWindow/CreateDiscreteMeshes.cs
+++ b/MatterControlLib/PartPreviewWindow/CreateDiscreteMeshes.cs
@@ -57,7 +57,7 @@ namespace MatterHackers.MatterControl
 
 			var totalBounds = meshToSplit.GetAxisAlignedBoundingBox();
 
-			var facesSharingVertex = meshToSplit.NewVertexFaceLists();
+			var facesSharingVertex = meshToSplit.GetVertexFaceLists();
 
 			for (int faceIndex = 0; faceIndex < faceCount; faceIndex++)
 			{
diff --git a/MatterControlLib/PartPreviewWindow/View3D/Actions/CombineObject3D_2.cs b/MatterControlLib/PartPreviewWindow/View3D/Actions/CombineObject3D_2.cs
index 4c406c6d7..1cb93a038 100644
--- a/MatterControlLib/PartPreviewWindow/View3D/Actions/CombineObject3D_2.cs
+++ b/MatterControlLib/PartPreviewWindow/View3D/Actions/CombineObject3D_2.cs
@@ -75,22 +75,7 @@ namespace MatterHackers.MatterControl.PartPreviewWindow.View3D
 
         public static void CheckManifoldData(CombineObject3D_2 item, IObject3D result)
         {
-            bool IsManifold(Mesh mesh)
-            {
-                var meshEdgeList = mesh.NewMeshEdges();
-
-                foreach (var meshEdge in meshEdgeList)
-                {
-                    if (meshEdge.Faces.Count() != 2)
-                    {
-                        return false;
-                    }
-                }
-
-                return true;
-            }
-
-            if (!IsManifold(result.Mesh))
+            if (!result.Mesh.IsManifold())
             {
                 // create a new combine of a and b and add it to the root
                 var combine = new CombineObject3D_2();
diff --git a/Submodules/agg-sharp b/Submodules/agg-sharp
index ada6ddc5f..732aaa728 160000
--- a/Submodules/agg-sharp
+++ b/Submodules/agg-sharp
@@ -1 +1 @@
-Subproject commit ada6ddc5f4848397e2270cac7420a00fa5ff08f7
+Subproject commit 732aaa728c1982b92b8451570a2ab26e7f0f8901