Work with the Twinjector a little and a light will go off, and you will get it. Heavy salt is tricky but way easier when you get how the Twinjector works. Dont rush, get the plastic at the same temp, fill the injectors put it on the block and push slow but positive. Try and get the mold ready with the block on it and in a place that is easy to get the injectors to without hesitation. You will get it. Frank