diff --git a/MatterControlLib/PartPreviewWindow/View3D/Actions/CombineObject3D_2.cs b/MatterControlLib/PartPreviewWindow/View3D/Actions/CombineObject3D_2.cs
index bcdb210eb..5cc926c37 100644
--- a/MatterControlLib/PartPreviewWindow/View3D/Actions/CombineObject3D_2.cs
+++ b/MatterControlLib/PartPreviewWindow/View3D/Actions/CombineObject3D_2.cs
@@ -204,7 +204,7 @@ namespace MatterHackers.MatterControl.PartPreviewWindow.View3D
 
                 if (set.Count > 1)
                 {
-#if false
+#if true
                     setMesh = BooleanProcessing.DoArray(set.Select(i => (i.mesh, i.matrix)),
                         CsgModes.Union,
                         Processing,
diff --git a/Submodules/agg-sharp b/Submodules/agg-sharp
index 171deb557..24fd0ee17 160000
--- a/Submodules/agg-sharp
+++ b/Submodules/agg-sharp
@@ -1 +1 @@
-Subproject commit 171deb5573a4497a73bf4497fcaae47d7264e1e1
+Subproject commit 24fd0ee1794410def5744f27520f0a06e5f8e736