diff --git a/EXE_GdbModifySurf.cpp b/EXE_GdbModifySurf.cpp
index f6df9d2..41265a3 100644
--- a/EXE_GdbModifySurf.cpp
+++ b/EXE_GdbModifySurf.cpp
@@ -1214,3 +1214,24 @@ ExeSurfBzTrim( int nId, int nCutterId)
    }
    return bOk ;
 }
+
+//----------------------------------------------------------------------------
+bool
+ExeSurfTmSetSmoothAng( int nId, double dAngDeg)
+{
+   IGeomDB* pGeomDB = GetCurrGeomDB() ;
+   VERIFY_GEOMDB( pGeomDB, false)
+   // recupero la superficie trimseh da trimmare
+   ISurfTriMesh* pSrfTm = GetSurfTriMesh( pGeomDB->GetGeoObj( nId)) ;
+   if ( pSrfTm == nullptr)
+      return false ;
+   pSrfTm->SetSmoothAngle( dAngDeg) ;
+   ExeSetModified() ;
+   // se richiesto, salvo il comando Lua equivalente
+   if ( IsCmdLog()) {
+      string sLua = "EgtSurfTmSetSmoothAng(" + ToString( nId) + "," +
+                                             ToString( dAngDeg) ;
+      LOG_INFO( GetCmdLogger(), sLua.c_str()) ;
+   }
+   return true ;
+}
diff --git a/LUA_GdbModifySurf.cpp b/LUA_GdbModifySurf.cpp
index 58e046d..1a5ac46 100644
--- a/LUA_GdbModifySurf.cpp
+++ b/LUA_GdbModifySurf.cpp
@@ -582,6 +582,22 @@ LuaSurfBzTrim( lua_State* L)
    return 1 ;
 }
 
+//-------------------------------------------------------------------------------
+static int
+LuaSurfTmSetSmoothAng( lua_State* L)
+{
+  // 2 parametri : nId, nCutterId
+   int nId ;
+   LuaCheckParam( L, 1, nId)
+   double dAngDeg ;
+   LuaCheckParam( L, 2, dAngDeg)
+   LuaClearStack( L) ;
+  // taglio la prima superficie in base alla seconda
+   bool bOk = ExeSurfTmSetSmoothAng( nId, dAngDeg) ;
+   LuaSetParam( L, bOk) ;
+   return 1 ;
+}
+
 //-------------------------------------------------------------------------------
 bool
 LuaInstallGdbModifySurf( LuaMgr& luaMgr)
@@ -616,5 +632,6 @@ LuaInstallGdbModifySurf( LuaMgr& luaMgr)
    bOk = bOk && luaMgr.RegisterFunction( "EgtSurfTmSetShowEdges", LuaSurfTmSetShowEdges) ;
    bOk = bOk && luaMgr.RegisterFunction( "EgtSurfTmGetShowEdges", LuaSurfTmGetShowEdges) ;
    bOk = bOk && luaMgr.RegisterFunction( "EgtSurfBzTrim", LuaSurfBzTrim) ;
+   bOk = bOk && luaMgr.RegisterFunction( "EgtSurfTmSetSmoothAng", LuaSurfTmSetSmoothAng) ;
    return bOk ;
 }