diff --git a/LuaLibs/CalcToolPath.lua b/LuaLibs/CalcToolPath.lua
index 8df029b..4a6772e 100644
--- a/LuaLibs/CalcToolPath.lua
+++ b/LuaLibs/CalcToolPath.lua
@@ -152,8 +152,13 @@ local function AddCurvesToToolPath( vEntIds, nTpathGrpId, nOrder, bInvert, vtSli
          end
       end
       
+      -- approssimo la curva e ne risetto il punto iniziale
+      local ptS = EgtSP( vIds[nIdx], GDB_ID.ROOT)
       EgtApproxCurve( vIds[nIdx], GDB_CA.ARCS, s_dApproxTol)
-            
+      if EgtCurveIsClosed( vIds[nIdx]) then
+         EgtChangeClosedCurveStartPoint( vIds[nIdx], ptS, GDB_RT.GLOB)
+      end
+
       EgtSetInfo( vEntIds[i], KEY_ASSOCIATED_TP_CRV, vIds[nIdx])
       EgtSetInfo( vIds[nIdx], KEY_ASSOCIATED_P_CRV, vEntIds[i])
 
@@ -1712,7 +1717,14 @@ local function CalcRibsToolPath( vEntIds, nRibsGrp, nTpathGrpId, LayerParams)
       local nNewEntId = EgtCopyGlob( vEntIds[i], nTpathGrpId, GDB_IN.LAST_SON)
       -- mi sposto dell'altezza layer
       EgtMove( nNewEntId, LayerParams.dLayHeight * LayerParams.vtSlicing, GDB_RT.GLOB)
+      
+      -- approssimo la curva e ne risetto punto iniziale (se chiusa)
+      local ptS = EgtSP( nNewEntId, GDB_ID.ROOT)
       EgtApproxCurve( nNewEntId, GDB_CA.ARCS, s_dApproxTol)
+      if EgtCurveIsClosed( nNewEntId) then
+         EgtChangeClosedCurveStartPoint( nNewEntId, ptS, GDB_RT.GLOB)
+      end
+      
       EgtModifyCurveExtrusion( nNewEntId, LayerParams.vtSlicing, GDB_RT.GLOB)
       EgtSetColor( nNewEntId, EgtStdColor('MAROON'))