Cov khoom ntawm peb lub tuam txhab chaw muaj nyob rau hauv cov khoom kho qhov chaw thiab qhov loj thiab cov khoom siv nrog ib qho meej, ua rau cov neeg siv khoom ua haujlwm tau zoo dua thaum xaiv, cov chaw tsim khoom txheem los ntawm lub chaw machining tau qhia rau hauv cov khoom txheem, koom tes nrog qhov tseeb ntawm cov khoom siv txiav kom ua hom fasteners txheem no, kev txhawb nqa tam sim ntawd, tsis muaj teeb meem yog kev cai lossis cov khoom txheem yuav khoom tuaj yeem lav nws qhov zoo heev.