Plastic injection-moulding is by far the most used technique to transform plastic into a product. I went to a company where they produce mostly automotive and medical parts..The most expensive thing with injection-moulding is the mould, but once you have it production is really cheap and fast. So the quantities of production is really high. And every time they put in a new mould/design the machine has to warm up which, this produces around around 200 ‘failed’ pieces before you actually start producing. The left-overs and waste are separated and shredded to use again. However they don’t use ‘used’ plastic themselves. Since it might slow down the machines, gives failures and simply because buying new is cheaper…

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