Dab tsi yog cov khoom ntawm qhov tsim nqi ntawm puab pwm?
Roughly speaking, tus nqi faib yog raws li nram no:
Txiav 65%
Workpiece khoom 20%
Kev kho cua kub 5%
Sib dhos / hloov 10%
Nws tseem qhia tau meej meej txog qhov tseem ceeb ntawm cov hlau zoo kev ua haujlwm thiab zoo zuag qhia tag nrho rau kev siv nyiaj txiag.