diff --git a/VolZmapVolume.cpp b/VolZmapVolume.cpp
index b563f56..aa31b3d 100644
--- a/VolZmapVolume.cpp
+++ b/VolZmapVolume.cpp
@@ -505,6 +505,7 @@ VolZmap::MillingStep( const Point3d& ptPs, const Vector3d& vtDs, const Vector3d&
       if ( vtAs.IsSmall()  ||  vtAe.IsSmall())
          return false ;
    }
+
   // Reset numero di parti
    m_nConnectedCompoCount = - 1 ;
 
@@ -538,35 +539,30 @@ bool
 VolZmap::MillingGeneralMotionStep( const Point3d& ptPs, const Vector3d& vtDs, const Vector3d& vtAs,
                                    const Point3d& ptPe, const Vector3d& vtDe, const Vector3d& vtAe)
 {
-   // Ciclo sulle mappe
-   double dAngDeg ;
-   vtDs.GetAngle( vtDe, dAngDeg) ;
-   int nNumSubStep = int( abs( dAngDeg) / 0.5) ;
-   Vector3d vtMove = ptPe - ptPs ;
-   double dLenPath = vtMove.Len() ;
-   double dDeltaLen = dLenPath / nNumSubStep ;
-   vtMove /= dLenPath ;
-   bool bSuccessful = true ;
-   for ( int n = 0 ; n < nNumSubStep + 1 &&  bSuccessful ; ++ n) {
-      double dPathSt = 0 ;
-      double dPathEn = 0.5 * dDeltaLen ;
-      if ( n == nNumSubStep) {
-         dPathSt = ( n - 0.5) * dDeltaLen ;
-         dPathEn = n * dDeltaLen ;
+  // Divido il movimento in tratti con direzione utensile costante
+   const double ANG_STEP = 0.5 ;
+   double dAngDeg ; vtDs.GetAngle( vtDe, dAngDeg) ;
+   int nStepCnt = int( abs( dAngDeg) / ANG_STEP) + 1 ;
+   bool bOk = true ;
+   Point3d ptSt = ptPs ;
+   for ( int i = 0 ; i <= nStepCnt && bOk ; ++ i) {
+      double dPosCoeff, dDirCoeff ;
+      if ( i < nStepCnt) {
+         dPosCoeff = ( i + 0.5) / nStepCnt ;
+         dDirCoeff = double( i) / nStepCnt ;
       }
-      else if ( n > 0) {
-         dPathSt = ( n - 0.5) * dDeltaLen ;
-         dPathEn = ( n + 0.5) * dDeltaLen ;
+      else {
+         dPosCoeff = 1 ;
+         dDirCoeff = 1 ;
       }
-      Point3d ptSt = ptPs + dPathSt * vtMove ;
-      Point3d ptEn = ptPs + dPathEn * vtMove ;
-      Vector3d vtD = ( dLenPath - dPathSt) * vtDs + dPathSt * vtDe ;
-      vtD.Normalize() ;
-      Vector3d vtA = ( dLenPath - dPathSt) * vtAs + dPathSt * vtAe ;
-      vtA.Normalize() ;
-      bSuccessful = bSuccessful  &&  MillingTranslationStep( ptSt, ptEn, vtD, vtA) ;
+      Point3d ptEn = Media( ptPs, ptPe, dPosCoeff) ;
+      Vector3d vtD = Media( vtDs, vtDe, dDirCoeff) ; vtD.Normalize() ;
+      Vector3d vtA = Media( vtAs, vtAe, dDirCoeff) ; vtA.Normalize() ;
+      bOk = bOk && MillingTranslationStep( ptSt, ptEn, vtD, vtA) ;
+     // aggiorno prossimo inizio
+      ptSt = ptEn ;
    }
-   return bSuccessful ;
+   return bOk ;
 }
 
 //----------------------------------------------------------------------------