E tele ituaiga o sikulima tu'ufa'atasia, e aofia ai fa'asili tu'ufa'atasi e lua ma fa'asili tu'ufa'atasi e tolu (fa'amea mafolafola ma fa'amago vaipuna po'o se fa'amafola mafolafola tu'ufa'atasi ma fa'amea puna puna) e tusa ai ma le ituaiga o mea fa'aoga tu'ufa'atasi;E tusa ai ma le ituaiga ulu, e mafai foʻi ona vaevaeina i faʻamau faʻapipiʻi pan ulu, faʻamau faʻapipiʻi ulu ulu, faʻamau faʻamalama i fafo, ma isi;E tusa ai ma meafaitino, ua vaevaeina i le carbon steel, stainless steel ma alloy steel (Vaega 12.9).