diff --git a/StandAlone/paths.lua b/StandAlone/paths.lua
index d35ec248..ff2a0ad9 100644
--- a/StandAlone/paths.lua
+++ b/StandAlone/paths.lua
@@ -120,7 +120,7 @@ Event.register({defines.events.on_built_entity,on_robot_built_entity}, function(
     local surface = entity.surface
     if sizes[entity.name] then
         local size = sizes[entity.name]
-        for x in 0,size do for y in 0,size do
+        for x = 0,size do for y = 0,size do
             local pos = {entity.position.x+x,entity.position.y+y}
             local tile = surface.get_tile(pos).name
             if math.random() < paths[tile]*size*10 then