For much of its history, tyremaking has been a multistage and highly labour intensive industry, involving building up the tyre carcass in layers manually on a drum. Each layer of material is often cut to length by hand before going off to be encased in its sidewall and tread components and then vulcanised. The introduction of automated processes has tended to be gradual and partial-evolutionary not revolutionary. Modern plants now have sequenced feeds and auto cutting of materials to the building drum, but the whole process would still be recognisable to the manufacturers of fifty years ago.