Endaweni yokuhlola uwoyela negesi, ukukhethwa kwemishini yokumba kungathinta kakhulu ukusebenza kahle nokusebenza nokusebenza kahle. Elinye lamathuluzi athandwa kakhulu asetshenziselwa ukubhola okujikelezayo yi-tricone bit, ikakhulukazi okuhlukile kwe-8 1/2 inch. Le bit ibonakala ngama-cones amathathu ajikelezayo, ngalinye lifakwe amazinyo abukhali aklanyelwe ukuchoboza ukwakheka kwamatshe, okwenza kube ukukhetha okufanelekile