diff --git a/StrategyLibs/BLADETOWASTE.lua b/StrategyLibs/BLADETOWASTE.lua
index 9bbb30d..55e2ece 100644
--- a/StrategyLibs/BLADETOWASTE.lua
+++ b/StrategyLibs/BLADETOWASTE.lua
@@ -791,11 +791,17 @@ local function UpdateDiceRaw( idRaw, idParallelTm, idPerpendicularTm, Part, Main
 
    -- box del cubetto in riferimento feature
    local b3Surf = EgtGetBBoxRef( idParallelTm, GDB_BB.STANDARD, frMainFace)
-   local b3SurfPerpendicular = EgtGetBBoxRef( idPerpendicularTm, GDB_BB.STANDARD, frMainFace)
-   b3Surf:Add( b3SurfPerpendicular)
+   if idPerpendicularTm then
+      local b3SurfPerpendicular = EgtGetBBoxRef( idPerpendicularTm, GDB_BB.STANDARD, frMainFace)
+      b3Surf:Add( b3SurfPerpendicular)
+   else
+      -- se non arriva la superficie perpendicolare è un solo taglio parallelo: si estende il box in Z in modo da uscire dal pezzo
+      local ptDeltaZ = b3Surf:getMax() + vtZ * ( MainFace.dElevation + 5)
+      b3Surf:Add( ptDeltaZ)
+   end
 
    -- estensione box per non avere problemi nella sottrazione booleana
-   if OtherFace then
+   if OtherFace and idPerpendicularTm then
       local vtY = vtZ ^ vtX
       local ptDeltaX = b3Surf:getMax() + vtX * 1
       local ptDeltaZ = b3Surf:getMax() + vtZ * 1