If you say so . <| sep |> Your description of it makes me want that eye pencil . Consider writing commercials ! <| sep |> Are you delivering Wood andor Plastic to the Tools factory ? You need one or the other with Steel to get an output I believe . Sorry if I missed it , I have skimmed over the images . If that is going wrong then the Construction Materials line will go wrong because Slag is an inefficient material that relies on the game choosing that particular recipe , seemingly at random if there is a demand for Slag . Check the other materials supply , and I would if I was you , though annoying , have a back up from a Quarry to the Construction Materials Factory . You can still compliment it will Slag when it gets produced but I had a huge bottleneck at mine when relying on Slag alone . Steel Mill needs a patch with recipes in my opinion .