diff --git a/ShowSolid.lua b/ShowSolid.lua
index 7653e2a..d0983f0 100644
--- a/ShowSolid.lua
+++ b/ShowSolid.lua
@@ -1,4 +1,4 @@
--- ShowSolid.lua by Egaltech s.r.l. 2020/10/05
+-- ShowSolid.lua by Egaltech s.r.l. 2020/10/06
 -- Gestione calcolo solido di una Trave
 
 require( 'EgtBase')
@@ -19,14 +19,14 @@ end
 
 -- Funzione per regolarizzare, se necessario, la superficie della feature
 local function RegularizeTriMesh( SurfId, DestGrpId, dStep)
-   -- solo per superfici trimesh con poche facce (max4)
+   ---- solo per superfici trimesh con poche facce (max 100)
    local nFacetCnt = EgtSurfTmFacetCount( SurfId)
-   if nFacetCnt > 4 then
+   if nFacetCnt > 100 then
       return SurfId
    end
    -- box della superficie
    local b3Surf = EgtGetBBox( SurfId, GDB_BB.STANDARD)
-   if not b3Surf or b3Surf:isEmpty() or b3Surf:getDimX() < 2 * dStep then
+   if not b3Surf or b3Surf:isEmpty() or b3Surf:getDimX() < 4 * dStep then
       return SurfId
    end
    -- recupero le facce e le divido in X
@@ -42,17 +42,19 @@ local function RegularizeTriMesh( SurfId, DestGrpId, dStep)
       for nI = 1, nStep do
          local dX1 = dX2
          dX2 = dX2 + dStep
-         if b3Fac:getMin():getX() < dX2 and b3Fac:getMax():getX() > dX1 then
+         if b3Fac:getMin():getX() < dX2 - GEO.EPS_SMALL and b3Fac:getMax():getX() > dX1 + GEO.EPS_SMALL then
             EgtCutSurfTmPlane( FacId, Point3d( dX1, 0, 0), -X_AX(), true) 
             EgtCutSurfTmPlane( FacId, Point3d( dX2, 0, 0), X_AX(), false)
             local LoopId = EgtExtractSurfTmFacetLoops( FacId, 0, DestGrpId)
-            EgtMergeCurvesInCurveCompo( LoopId, 0.001)
-            local TmpSurfId = EgtSurfTmByFlatContour( DestGrpId, LoopId, 0.01)
-            EgtErase( LoopId)
-            if NewSurfId then
-               NewSurfId = EgtSurfTmBySewing( DestGrpId, {NewSurfId, TmpSurfId})
-            else
-               NewSurfId = TmpSurfId
+            if LoopId then
+               EgtMergeCurvesInCurveCompo( LoopId, 0.001)
+               local TmpSurfId = EgtSurfTmByFlatContour( DestGrpId, LoopId, 0.01)
+               EgtErase( LoopId)
+               if NewSurfId then
+                  NewSurfId = EgtSurfTmBySewing( DestGrpId, {NewSurfId, TmpSurfId})
+               else
+                  NewSurfId = TmpSurfId
+               end
             end
             EgtErase( FacId)
             FacId = EgtCopySurfTmFacet( SurfId, nF, DestGrpId)