The term “swarf”, when related to metal roofing, describes waste metallic debris left on the roof, such as bits of tie-wire, screws and poprivit shafts as well as shavings and chips created by drilling and cutting roof panels are commonly called “swarf”. Drill shavings are the result of self-drilling screws. Such screws remove material from the metal skin and deposit it on the roof panels in order to pilot their hole. Swarf will inevitably rust very quickly if it is not removed soon after being created. Click here to read the entire article.