diff --git a/src/Mod/Assembly/App/opendcm/core/imp/kernel_imp.hpp b/src/Mod/Assembly/App/opendcm/core/imp/kernel_imp.hpp
index 9e9f8085d..cd2ae8d5a 100644
--- a/src/Mod/Assembly/App/opendcm/core/imp/kernel_imp.hpp
+++ b/src/Mod/Assembly/App/opendcm/core/imp/kernel_imp.hpp
@@ -21,6 +21,7 @@
 #define DCM_KERNEL_IMP_H
 
 #include "../kernel.hpp"
+#include <Base/Console.h>
 #include <boost/math/special_functions.hpp>
 #include <Eigen/QR>
 
@@ -62,9 +63,7 @@ void Dogleg<Kernel>::calculateStep(const Eigen::MatrixBase<Derived>& g, const Ei
     const typename Kernel::Vector h_gn = jacobi.fullPivLu().solve(-residual);
     const double eigen_error = (jacobi*h_gn + residual).norm();
 #ifdef USE_LOGGING
-    BOOST_LOG(log)<< "Gauss Newton error: "<<eigen_error;
-
-    if(!boost::math::isfinite(h_gn.norm())) {
+   if(!boost::math::isfinite(h_gn.norm())) {
         BOOST_LOG(log)<< "Unnormal gauss-newton detected: "<<h_gn.norm();
     }
 
@@ -81,9 +80,6 @@ void Dogleg<Kernel>::calculateStep(const Eigen::MatrixBase<Derived>& g, const Ei
     // compute the dogleg step
     if(h_gn.norm() <= delta) {
         h_dl = h_gn;
-#ifdef USE_LOGGING
-        BOOST_LOG(log)<< "Gauss Newton Step: "<<eigen_error;
-#endif
     }
     else if((alpha*h_sd).norm() >= delta) {
         //h_dl = alpha*h_sd;
@@ -94,8 +90,6 @@ void Dogleg<Kernel>::calculateStep(const Eigen::MatrixBase<Derived>& g, const Ei
             BOOST_LOG(log)<< "Unnormal dogleg descent detected: "<<h_dl.norm();
         }
 
-        BOOST_LOG(log)<< "Steepest Descend step";
-
 #endif
     }
     else {
@@ -131,8 +125,6 @@ void Dogleg<Kernel>::calculateStep(const Eigen::MatrixBase<Derived>& g, const Ei
             BOOST_LOG(log)<< "Unnormal dogleg beta detected: "<<beta;
         }
 
-        BOOST_LOG(log)<< "Dogleg Step";
-
 #endif
     }
 };
@@ -343,7 +335,7 @@ Kernel<Scalar, Nonlinear>::MappedEquationSystem::MappedEquationSystem(int params
       m_parameter(params), m_residual(equations),
       m_params(params), m_eqns(equations), Scaling(1.),
       Jacobi(&m_jacobi(0,0),equations,params,DynStride(equations,1)),
-      Parameter(&m_parameter(0),params,DynStride(1,1)), 
+      Parameter(&m_parameter(0),params,DynStride(1,1)),
       Residual(&m_residual(0),equations,DynStride(1,1)) {
 
     m_param_rot_offset = 0;
@@ -421,21 +413,22 @@ void Kernel<Scalar, Nonlinear>::MappedEquationSystem::setAccess(AccessType t) {
     if(t==complete) {
         new(&Jacobi) MatrixMap(&m_jacobi(0,0),m_eqns,m_params,DynStride(m_eqns,1));
         new(&Parameter) VectorMap(&m_parameter(0),m_params,DynStride(1,1));
-	new(&Residual)  VectorMap(&m_residual(0), m_eqns,  DynStride(1,1));
+        new(&Residual)  VectorMap(&m_residual(0), m_eqns,  DynStride(1,1));
     }
     else if(t==rotation) {
         int num = m_param_trans_offset;
         new(&Jacobi) MatrixMap(&m_jacobi(0,0),m_eqn_trans_offset,num,DynStride(m_eqns,1));
         new(&Parameter) VectorMap(&m_parameter(0),num,DynStride(1,1));
-	new(&Residual)  VectorMap(&m_residual(0), m_eqn_trans_offset,  DynStride(1,1));
+        new(&Residual)  VectorMap(&m_residual(0), m_eqn_trans_offset,  DynStride(1,1));
     }
     else if(t==general) {
         int num = m_params - m_param_trans_offset;
         int eq_num = m_eqns - m_eqn_trans_offset;
         new(&Jacobi) MatrixMap(&m_jacobi(m_eqn_trans_offset,m_param_trans_offset),eq_num,num,DynStride(m_eqns,1));
         new(&Parameter) VectorMap(&m_parameter(m_param_trans_offset),num,DynStride(1,1));
-	new(&Residual)  VectorMap(&m_residual(m_eqn_trans_offset), eq_num,  DynStride(1,1));
+        new(&Residual)  VectorMap(&m_residual(m_eqn_trans_offset), eq_num,  DynStride(1,1));
     }
+
     m_access = t;
 };
 
@@ -443,11 +436,11 @@ template<typename Scalar, template<class> class Nonlinear>
 bool Kernel<Scalar, Nonlinear>::MappedEquationSystem::hasAccessType(AccessType t) {
 
     if(t==rotation)
-        return (m_param_rot_offset>0);
+        return (m_param_rot_offset>0 && m_eqn_rot_offset>0);
     else if(t==general)
-        return (m_param_trans_offset<m_params);
+        return (m_param_trans_offset<m_params && m_eqn_trans_offset<m_eqns);
     else
-        return (m_params>0);
+        return (m_params>0 && m_eqns>0);
 };
 
 template<typename Scalar, template<class> class Nonlinear>
diff --git a/src/Mod/Assembly/App/opendcm/module3d/imp/solver_imp.hpp b/src/Mod/Assembly/App/opendcm/module3d/imp/solver_imp.hpp
index b4b843c43..77e6e0fc7 100644
--- a/src/Mod/Assembly/App/opendcm/module3d/imp/solver_imp.hpp
+++ b/src/Mod/Assembly/App/opendcm/module3d/imp/solver_imp.hpp
@@ -107,12 +107,12 @@ SystemSolver<Sys>::Rescaler::Rescaler(boost::shared_ptr<Cluster> c, Mes& m) : cl
 
 template<typename Sys>
 void SystemSolver<Sys>::Rescaler::operator()() {
-    mes.Scaling = scaleClusters();
+    mes.Scaling = scaleClusters(calculateScale());
     rescales++;
 };
 
 template<typename Sys>
-typename SystemSolver<Sys>::Scalar SystemSolver<Sys>::Rescaler::scaleClusters() {
+typename SystemSolver<Sys>::Scalar SystemSolver<Sys>::Rescaler::calculateScale() {
 
     typedef typename Cluster::cluster_iterator citer;
     std::pair<citer, citer> cit = cluster->clusters();
@@ -134,6 +134,12 @@ typename SystemSolver<Sys>::Scalar SystemSolver<Sys>::Rescaler::scaleClusters()
         sc = (s>sc) ? s : sc;
     }
 
+    return sc;
+}
+
+template<typename Sys>
+typename SystemSolver<Sys>::Scalar SystemSolver<Sys>::Rescaler::scaleClusters(Scalar sc) {
+
     //if no scaling-value returned we can use 1
     sc = (Kernel::isSame(sc,0, 1e-10)) ? 1. : sc;
 
@@ -357,20 +363,33 @@ void SystemSolver<Sys>::solveCluster(boost::shared_ptr<Cluster> cluster, Sys& sy
 
             //if(!has_cycle) {
 #ifdef USE_LOGGING
-                BOOST_LOG(log)<< "non-cyclic system dedected: solve rotation only";
+            BOOST_LOG(log)<< "non-cyclic system dedected: solve rotation only";
 #endif
-                //cool, lets do uncylic. first all rotational constraints with rotational parameters
-                mes.setAccess(rotation);
+            //cool, lets do uncylic. first all rotational constraints with rotational parameters
+            mes.setAccess(rotation);
 
-                //solve can be done without catching exceptions, because this only fails if the system is
-                //unsolvable. We need the rescaler here two as unscaled rotations may be unprecise if the
-                //parts are big (as ne the normals are always 1) and then distances may not be possible
-                //to solve correctly with only translations
-                Rescaler re(cluster, mes);
-                re();
+            //rotations need to be calculated in a scaled manner. thats because the normales used for
+            //rotation calculation are always 1, no matter how big the part is. This can lead to problems
+            //when for example two rotated faces have a precision error on the parallel normals but a distance
+            //at the outer edges is far bigger than the precision as the distance from normal origin to outer edge
+            //is bigger 1. that would lead to unsolvable translation-only systems.
+
+            //solve need to catch exceptions to reset the mes scaling on failure
+            Rescaler re(cluster, mes);
+            mes.Scaling = 1./(re.calculateScale()*SKALEFAKTOR);
+
+            try {
                 sys.kernel().solve(mes, re);
+                mes.Scaling = 1.;
+            }
+            catch(...) {
+                mes.Scaling = 1.;
+                throw;
+            }
+
+            //now let's see if we have to go on with the translations
+            if(mes.hasAccessType(general)) {
 
-                //now let's see if we have to go on with the translations
                 mes.setAccess(general);
                 mes.recalculate();
 
@@ -392,6 +411,8 @@ void SystemSolver<Sys>::solveCluster(boost::shared_ptr<Cluster> cluster, Sys& sy
                         done = false;
                     }
                 }
+            };
+
             //};
 
             //not done already? try it the hard way!
diff --git a/src/Mod/Assembly/App/opendcm/module3d/solver.hpp b/src/Mod/Assembly/App/opendcm/module3d/solver.hpp
index 0379b7d14..45e750ac9 100644
--- a/src/Mod/Assembly/App/opendcm/module3d/solver.hpp
+++ b/src/Mod/Assembly/App/opendcm/module3d/solver.hpp
@@ -84,7 +84,8 @@ struct SystemSolver : public Job<Sys> {
 
         void operator()();
 
-        Scalar scaleClusters();
+	Scalar calculateScale();
+        Scalar scaleClusters(Scalar sc);
         void collectPseudoPoints(boost::shared_ptr<Cluster> parent,
                                  LocalVertex cluster,
                                  std::vector<typename Kernel::Vector3,