diff --git a/SurfRoughing.cpp b/SurfRoughing.cpp
index f40125d..4fb4751 100644
--- a/SurfRoughing.cpp
+++ b/SurfRoughing.cpp
@@ -1632,6 +1632,8 @@ SurfRoughing::AddPocket( const INTVECTOR& vPocket, const Vector3d& vtTool, const
    double dSafeZ = GetSafeZ() ;
   // lunghezza di approccio/retrazione
    double dAppr = m_Params.m_dStartPos ;
+  // recupero il tipo di svuotatura
+   int nSubType = m_Params.m_nSubType ;
 
   // ciclo sulle regioni
    bool bStart = true ;
@@ -1639,10 +1641,16 @@ SurfRoughing::AddPocket( const INTVECTOR& vPocket, const Vector3d& vtTool, const
 
      // recupero la superficie da lavorare
       const ISurfFlatRegion* pSfr = GetSurfFlatRegion( m_pGeomDB->GetGeoObj( nPockId)) ;
+     // controllo se la regione è relativa ad uno step base o ad uno step intermedio
+      bool bIsSubStep = ( pSfr->GetTempProp( 0) == 1) ;
+     // se il tipo è SPIRAL_OUT e sto gestendo uno step intermedio, lo lavoro come SPIRAL_IN
+      if ( nSubType == SURFROU_SUB_SPIRALOUT  &&  bIsSubStep)
+         nSubType = SURFROU_SUB_SPIRALIN ;
+
       ICRVCOMPOPOVECTOR vpCrvs ; // percorso di svuotatura
      // se si tratta di uno step base, allora lavoro l'intera superficie
       if ( ! CalcPocketing( pSfr, m_TParams.m_dDiam / 2, 0., m_Params.m_dSideStep, m_Params.m_dSideAngle,
-                         m_Params.m_nSubType, true, vpCrvs)) {
+                            nSubType, true, vpCrvs)) {
          m_pMchMgr->SetLastError( 3028, "Error in SurfRoughing : Error in CalcPocketing") ;
          return false ;
       }
@@ -1686,7 +1694,7 @@ SurfRoughing::AddPocket( const INTVECTOR& vPocket, const Vector3d& vtTool, const
                Point3d ptUp = ptStart ;
                if ( bOutStart)
                   pCurve->GetEndPoint( ptUp) ;
-               else if ( m_Params.m_nSubType == SURFROU_SUB_SPIRALIN)
+               else if ( nSubType == SURFROU_SUB_SPIRALIN)
                   if ( ! CalcRetCrv( vpCrvs[k], ptUp, bOutStart, pRCrv))
                      return false ;
               // determino inizio attacco
@@ -1734,8 +1742,8 @@ SurfRoughing::AddPocket( const INTVECTOR& vPocket, const Vector3d& vtTool, const
                if ( IsNull( pCompo))
                   return false ;
                if ( ! AddLeadIn( ptP1, ptStart, vtStart, vtExtr, pCompo,
-                                 ( ( m_Params.m_nSubType == SURFROU_SUB_SPIRALIN  ||  m_Params.m_nSubType == SURFROU_SUB_SPIRALOUT)) ? Get( pRCrv) : nullptr,
-                                 ( m_Params.m_nSubType == SURFROU_SUB_SPIRALOUT) ? m_Params.m_bInvert : ! m_Params.m_bInvert,
+                                 ( ( nSubType == SURFROU_SUB_SPIRALIN  ||  nSubType == SURFROU_SUB_SPIRALOUT)) ? Get( pRCrv) : nullptr,
+                                 ( nSubType == SURFROU_SUB_SPIRALOUT) ? m_Params.m_bInvert : ! m_Params.m_bInvert,
                                   bSplitArcs, bOutStart, false)) {
                   m_pMchMgr->SetLastError( 3013, "Error in SurfRoughing : LeadIn not computable") ;
                   return false ;
@@ -1774,7 +1782,7 @@ SurfRoughing::AddPocket( const INTVECTOR& vPocket, const Vector3d& vtTool, const
                Point3d ptP1 ;
                SetFeed( GetEndFeed()) ;
                if ( ! AddLeadOut( ptEnd, vtEnd, vtExtr,
-                                  ( ( m_Params.m_nSubType == SURFROU_SUB_SPIRALIN  ||  m_Params.m_nSubType == SURFROU_SUB_SPIRALOUT)) ? Get( pRCrv) : nullptr,
+                                  ( ( nSubType == SURFROU_SUB_SPIRALIN  ||  nSubType == SURFROU_SUB_SPIRALOUT)) ? Get( pRCrv) : nullptr,
                                   bSplitArcs, false, ptP1, dEndElev)) {
                   m_pMchMgr->SetLastError( 3014, "Error in SurfRoughing : LeadOut not computable") ;
                   return false ;