diff --git a/Pocketing.cpp b/Pocketing.cpp
index c3827b4..83bdaf7 100644
--- a/Pocketing.cpp
+++ b/Pocketing.cpp
@@ -2006,6 +2006,9 @@ Pocketing::AddZigZag( const ICurveComposite* pCompo, const Vector3d& vtTool, con
                   double dStElev ;
                   if ( ! GetElevation( m_nPhase, ptStart - 10 * EPS_SMALL * vtTool, vtTool, GetRadiusForStartEndElevation(), vtTool, dStElev))
                      dStElev = dElev ;
+                  bool bUnderStart = m_bAboveHead && GetPointUnderRaw( ptP1, vtTool, GetRadiusForStartEndElevation(), m_TParams.m_dLen, false, dSafeZ, dStElev) ;
+                  if ( bUnderStart)
+                     dStElev = max( dStElev, dElev) ;
                   dStElev -= ( ptP1 - ptStart) * vtExtr ;
                  // se inizio, approccio globale al punto iniziale
                   if ( bStart) {
@@ -2142,6 +2145,9 @@ Pocketing::AddZigZag( const ICurveComposite* pCompo, const Vector3d& vtTool, con
                   double dStElev ;
                   if ( ! GetElevation( m_nPhase, ptStart - 10 * EPS_SMALL * vtTool, vtTool, GetRadiusForStartEndElevation(), vtTool, dStElev))
                      dStElev = dElev ;
+                  bool bUnderStart = m_bAboveHead && GetPointUnderRaw( ptP1, vtTool, GetRadiusForStartEndElevation(), m_TParams.m_dLen, false, dSafeZ, dStElev) ;
+                  if ( bUnderStart)
+                     dStElev = max( dStElev, dElev) ;
                   dStElev -= ( ptP1 - ptStart) * vtExtr ;
                  // se attacco a zigzag o a spirale o a scivolo, l'elevazione va nell'attacco
                   if ( GetLeadInType() == POCKET_LI_ZIGZAG  ||
@@ -2505,6 +2511,9 @@ Pocketing::AddOneWay( const ICurveComposite* pCompo, const Vector3d& vtTool, con
                   double dStElev ;
                   if ( ! GetElevation( m_nPhase, ptStart - 10 * EPS_SMALL * vtTool, vtTool, GetRadiusForStartEndElevation(), vtTool, dStElev))
                      dStElev = dElev ;
+                  bool bUnderStart = m_bAboveHead && GetPointUnderRaw( ptP1, vtTool, GetRadiusForStartEndElevation(), m_TParams.m_dLen, false, dSafeZ, dStElev) ;
+                  if ( bUnderStart)
+                     dStElev = max( dStElev, dElev) ;
                   dStElev -= ( ptP1 - ptStart) * vtExtr ;
                  // se attacco a zigzag o a spirale o a scivolo, l'elevazione va nell'attacco
                   if ( GetLeadInType() == POCKET_LI_ZIGZAG  ||
@@ -2655,6 +2664,9 @@ Pocketing::AddOneWay( const ICurveComposite* pCompo, const Vector3d& vtTool, con
                double dStElev ;
                if ( ! GetElevation( m_nPhase, ptS - 10 * EPS_SMALL * vtTool, vtTool, GetRadiusForStartEndElevation(), vtTool, dStElev))
                   dStElev = dElev ;
+               bool bUnderStart = m_bAboveHead && GetPointUnderRaw( ptP, vtTool, GetRadiusForStartEndElevation(), m_TParams.m_dLen, false, dSafeZ, dStElev) ;
+               if ( bUnderStart)
+                  dStElev = max( dStElev, dElev) ;
                dStElev -= ( ptP - ptS) * vtExtr ;
               // sempre approccio di collegamento
                if ( ! AddLinkApproach( ptP, vtTool, dSafeZ, dSafeAggrBottZ, dStElev, dAppr)) {
@@ -2796,8 +2808,10 @@ Pocketing::AddSpiralIn( const ICurveComposite* pCompo, const Vector3d& vtTool, c
                   double dStElev ;
                   if ( ! GetElevation( m_nPhase, ptStart - 10 * EPS_SMALL * vtTool, vtTool, GetRadiusForStartEndElevation(), vtTool, dStElev))
                      dStElev = dElev ;
-                  dStElev -= ( ptP1 - ptStart) * vtExtr ;
                   bool bUnderStart = m_bAboveHead && GetPointUnderRaw( ptP1, vtTool, GetRadiusForStartEndElevation(), m_TParams.m_dLen, false, dSafeZ, dStElev) ;
+                  if ( bUnderStart)
+                     dStElev = max( dStElev, dElev) ;
+                  dStElev -= ( ptP1 - ptStart) * vtExtr ;
                  // se attacco a zigzag o a spirale o a scivolo, l'elevazione va nell'attacco
                   if ( GetLeadInType() == POCKET_LI_ZIGZAG  ||
                        GetLeadInType() == POCKET_LI_HELIX  ||
@@ -2978,6 +2992,9 @@ Pocketing::AddSpiralOut( const ICurveComposite* pCompo, const Vector3d& vtTool,
                   double dStElev ;
                   if ( ! GetElevation( m_nPhase, ptStart - 10 * EPS_SMALL * vtTool, vtTool, GetRadiusForStartEndElevation(), vtTool, dStElev))
                      dStElev = dElev ;
+                  bool bUnderStart = m_bAboveHead && GetPointUnderRaw( ptP1, vtTool, GetRadiusForStartEndElevation(), m_TParams.m_dLen, false, dSafeZ, dStElev) ;
+                  if ( bUnderStart)
+                     dStElev = max( dStElev, dElev) ;
                   dStElev -= ( ptP1 - ptStart) * vtExtr ;
                  // se attacco a zigzag o a spirale o a scivolo, l'elevazione va nell'attacco
                   if ( GetLeadInType() == POCKET_LI_ZIGZAG  ||