diff --git a/WaterJetting.cpp b/WaterJetting.cpp
index 75b4f7e..cfe256d 100644
--- a/WaterJetting.cpp
+++ b/WaterJetting.cpp
@@ -3033,8 +3033,11 @@ WaterJetting::CalcOffset( ICurveComposite* pCompo, double dSignOffs)
       if ( OffsCrv.Make( pCompo, dSignOffs, nFlag)) {
          ICurve* pOffs = OffsCrv.GetLongerCurve() ;
          if ( pOffs != nullptr) {
+            Vector3d vtExtr ; pCompo->GetExtrusion( vtExtr) ;
             pCompo->Clear() ;
             pCompo->AddCurve( pOffs) ;
+           // ripristino estrusione della curva compo ( rimossa dal Clear)
+            pCompo->SetExtrusion( vtExtr) ;
             bOk = true ;
          }
       }