Mchira wa screw tail screw uli ngati mchira wobowola kapena mchira wosongoka. Sichiyenera kubowola mabowo pa workpiece poyamba, ndipo akhoza mwachindunji kubowola, kugogoda, ndi loko pa zoikamo zinthu ndi m'munsi. Poyerekeza ndi zomangira wamba, kubowola mchira wononga Kukhazikika kwakukulu ndi mphamvu yosungira, sikudzamasuka pakapita nthawi yayitali yosakanikirana, yosavuta komanso yotetezeka kugwiritsira ntchito, kubowola ndi kugogoda kumatha kutha mu ntchito imodzi, kupulumutsa nthawi, ntchito ndi ntchito. Zomangira zomangira zimagwiritsidwa ntchito makamaka kukonza zitsulo monga zomangira zitsulo, zomwe zimagwiritsidwa ntchito pokhoma mbale zachitsulo ndi mbale zopanda zitsulo, monga kukonza matabwa a silicon-calcium, matabwa a gypsum ndi matabwa osiyanasiyana amatabwa pazitsulo zachitsulo. Zomangira zokhala ndi kamangidwe koyenera zimatha kupangitsa chitsulo ndi mbale zokwerera kukhala zokhoma molimba, kupewa kuwonongeka ndi kukwapula kwa mbale yokwerera, ndipo ndizosavuta kuyiyika.