diff --git a/Sawing.cpp b/Sawing.cpp
index ef957b8..9361754 100644
--- a/Sawing.cpp
+++ b/Sawing.cpp
@@ -2138,12 +2138,14 @@ Sawing::GenerateLineCl( const ICurveLine* pLine, const Vector3d& vtTool, const V
    }
    if ( dActBstep < EPS_SMALL)
       dActBstep = dActStep ;
+   double dActLstep = GetStepLast() ;
   // direzione della linea
    Vector3d vtDir ; pLine->GetStartDir( vtDir) ;
 
   // Se una sola passata
-   if ( dActStep < EPS_SMALL  ||  ( dElev - dExtraCut) <= dActStep  ||
-        ( ! bSideAng  &&  m_Params.m_dStepLast > EPS_SMALL  &&  ( dElev - dExtraCut) <= m_Params.m_dStepLast)) {
+   if ( m_Params.m_nStepType != SAW_ST_TOANDFROM  &&
+        ( dActStep < EPS_SMALL  ||  ( dElev - dExtraCut) <= dActStep  ||
+          ( ! bSideAng  &&  dActLstep > EPS_SMALL  &&  ( dElev - dExtraCut) <= dActLstep))) {
      // 1 -> approccio
       Point3d ptP1 = pLine->GetStart() - vtDir * m_Params.m_dLiTang ;
       if ( ! AddApproach( ptP1, vtCorr, dSafeZ, dElev, dAppr))
@@ -2240,11 +2242,17 @@ Sawing::GenerateLineCl( const ICurveLine* pLine, const Vector3d& vtTool, const V
       int nStep = 2 ;
       if ( m_Params.m_nStepType == SAW_ST_ZIGZAG)
          nStep = 2 * static_cast<int>( ceil( dCutH / ( dActStep + dActBstep + EPS_SMALL))) ;
+      else {
+         if ( dActStep < EPS_SMALL)
+            dActStep = dCutH / nStep ;
+         if ( dActBstep < EPS_SMALL)
+            dActBstep = dCutH / nStep ;
+      }
       double dMeanStep = dCutH / nStep ;
       double dBstep = dActBstep * 2 * dMeanStep / ( dActStep + dActBstep) ;
       double dLastStep = dBstep ;
-      if ( ! bSideAng  &&  m_Params.m_dStepLast > EPS_SMALL) {
-         dLastStep = m_Params.m_dStepLast ;
+      if ( ! bSideAng  &&  dActLstep > EPS_SMALL) {
+         dLastStep = dActLstep ;
          double dCoeff = ( dCutH - dLastStep) / ( nStep / 2 * dActStep + ( nStep / 2 - 1) * dActBstep) ;
          dMeanStep = dCoeff * ( dActStep + dActBstep) / 2 ;
          dBstep = dCoeff * dActBstep ;
@@ -2286,8 +2294,8 @@ Sawing::GenerateLineCl( const ICurveLine* pLine, const Vector3d& vtTool, const V
       int nStep = static_cast<int>( ceil( dCutH / ( dActStep + EPS_SMALL))) ;
       double dStep = dCutH / nStep ;
       double dLastStep = dStep ;
-      if ( ! bSideAng  &&  m_Params.m_dStepLast > EPS_SMALL) {
-         dLastStep = m_Params.m_dStepLast ;
+      if ( ! bSideAng  &&  dActLstep > EPS_SMALL) {
+         dLastStep = dActLstep ;
          nStep = static_cast<int>( ceil( ( dCutH - dLastStep) / ( dActStep + EPS_SMALL))) + 1 ;
          dStep = ( dCutH - dLastStep) / ( nStep - 1) ;
       }