Makina athu otambasulira filimu adapangidwa kuti azigwira bwino ntchito. Ndi kutambasula kwapamwamba komanso kulimba, imateteza katundu ndi kuphweka ntchito zolongedza ndi makina. Zimapereka kumatirira ndi mphamvu zabwino kwambiri, kuonetsetsa kuti katunduyo amakulungidwa bwino poyenda ndi kusungirako. Zoyenera kuchita zokha, zimapulumutsa nthawi ndi khama.