diff --git a/FDTD/operator.cpp b/FDTD/operator.cpp
index 6c1b473..70c99a3 100644
--- a/FDTD/operator.cpp
+++ b/FDTD/operator.cpp
@@ -17,6 +17,7 @@
 
 #include <fstream>
 #include "operator.h"
+#include "engine.h"
 #include "operator_extension.h"
 #include "processfields.h"
 #include "tools/array_ops.h"
@@ -43,6 +44,12 @@ Operator::~Operator()
 	Reset();
 }
 
+Engine* Operator::CreateEngine()
+{
+	Engine* eng = Engine::New(this);
+	return eng;
+}
+
 void Operator::Init()
 {
 	CSX = NULL;
diff --git a/FDTD/operator.h b/FDTD/operator.h
index b924923..3450705 100644
--- a/FDTD/operator.h
+++ b/FDTD/operator.h
@@ -24,6 +24,7 @@
 #include "excitation.h"
 
 class Operator_Extension;
+class Engine;
 
 //! Abstract base-class for the FDTD-operator
 class Operator
@@ -34,6 +35,8 @@ public:
 	static Operator* New();
 	virtual ~Operator();
 
+	virtual Engine* CreateEngine();
+
 	virtual bool SetGeometryCSX(ContinuousStructure* geo);
 	virtual ContinuousStructure* GetGeometryCSX() {return CSX;}
 
diff --git a/FDTD/operator_cylinder.cpp b/FDTD/operator_cylinder.cpp
index e7ba875..862e9d3 100644
--- a/FDTD/operator_cylinder.cpp
+++ b/FDTD/operator_cylinder.cpp
@@ -15,6 +15,7 @@
 *	along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include "engine.h"
 #include "operator_cylinder.h"
 #include "operator_extension.h"
 #include "operator_ext_cylinder.h"
@@ -35,6 +36,13 @@ Operator_Cylinder::~Operator_Cylinder()
 	Operator::Reset();
 }
 
+Engine* Operator_Cylinder::CreateEngine()
+{
+	//!create a confentional engine... cylinder special operations will be dealt by engine extentions
+	Engine* eng = Engine::New(this);
+	return eng;
+}
+
 void Operator_Cylinder::Init()
 {
 	CC_closedAlpha = false;
diff --git a/FDTD/operator_cylinder.h b/FDTD/operator_cylinder.h
index 3505c19..b4257da 100644
--- a/FDTD/operator_cylinder.h
+++ b/FDTD/operator_cylinder.h
@@ -30,6 +30,8 @@ class Operator_Cylinder : public Operator
 public:
 	static Operator_Cylinder* New();
 	virtual ~Operator_Cylinder();
+
+	virtual Engine* CreateEngine();
 	
 	virtual bool SetGeometryCSX(ContinuousStructure* geo);
 
diff --git a/FDTD/operator_sse.cpp b/FDTD/operator_sse.cpp
index 8b09d33..883d67a 100644
--- a/FDTD/operator_sse.cpp
+++ b/FDTD/operator_sse.cpp
@@ -15,6 +15,7 @@
 *	along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include "engine_sse.h"
 #include "operator_sse.h"
 #include "tools/array_ops.h"
 
@@ -34,6 +35,13 @@ Operator_sse::~Operator_sse()
 	Reset();
 }
 
+Engine* Operator_sse::CreateEngine()
+{
+	//!create a special sse-engine
+	Engine_sse* eng = Engine_sse::New(this);
+	return eng;
+}
+
 void Operator_sse::Init()
 {
 	Operator::Init();
diff --git a/FDTD/operator_sse.h b/FDTD/operator_sse.h
index 7d04ad8..c133beb 100644
--- a/FDTD/operator_sse.h
+++ b/FDTD/operator_sse.h
@@ -28,6 +28,8 @@ public:
 	static Operator_sse* New();
 	virtual ~Operator_sse();
 
+	virtual Engine* CreateEngine();
+
 	inline virtual FDTD_FLOAT& GetVV( unsigned int n, unsigned int x, unsigned int y, unsigned int z ) const { return f4_vv[n][x][y][z%numVectors].f[z/numVectors]; }
 	inline virtual FDTD_FLOAT& GetVI( unsigned int n, unsigned int x, unsigned int y, unsigned int z ) const { return f4_vi[n][x][y][z%numVectors].f[z/numVectors]; }
 
diff --git a/openems.cpp b/openems.cpp
index 193de86..989c4d0 100644
--- a/openems.cpp
+++ b/openems.cpp
@@ -252,35 +252,12 @@ int openEMS::SetupFDTD(const char* file)
 	cout << "Creation time for operator: " << difftime(OpDoneTime,startTime) << " s" << endl;
 
 	//create FDTD engine
-	if (CylinderCoords)
+	if (m_engine==EngineType_Multithreaded)
 	{
-		cerr << "openEMS: creating cylinder coordinate FDTD engine..." << endl;
-		switch (m_engine) {
-//		case EngineType_Multithreaded:
-//			FDTD_Eng = Engine_Multithread::New(FDTD_Op,m_engine_numThreads);
-//			break;
-//		case EngineType_SSE:
-//			FDTD_Eng = Engine_sse::New(dynamic_cast<Operator_sse*>(FDTD_Op));
-//			break;
-		default:
-			FDTD_Eng = Engine::New(FDTD_Op);
-			break;
-		}
+		FDTD_Eng = Engine_Multithread::New(FDTD_Op,m_engine_numThreads);
 	}
 	else
-	{
-		switch (m_engine) {
-		case EngineType_Multithreaded:
-			FDTD_Eng = Engine_Multithread::New(FDTD_Op,m_engine_numThreads);
-			break;
-		case EngineType_SSE:
-			FDTD_Eng = Engine_sse::New(dynamic_cast<Operator_sse*>(FDTD_Op));
-			break;
-		default:
-			FDTD_Eng = Engine::New(FDTD_Op);
-			break;
-		}
-	}
+		FDTD_Eng = FDTD_Op->CreateEngine();
 
 	//*************** setup processing ************//
 	cout << "Setting up processing..." << endl;