1. Lub ntsiab yog vim li cas rau qhov cuam tshuam ntawm cov cuab yeej kho vajtse eccentricity yog tias ib tug tuag yog tsis ruaj khov. Nyob rau hauv lub tsim ntawm screws on txias piers, lub sim neej ib qho tuag tsis ruaj khov. Nws yog ib qho yooj yim heev uas yuav ua rau ntau lub phenomenal undesirable nyob rau hauv cov hlau hlau ua.
2, nws kuj yog ua tau hais tias lub plhaub pub yog tsis tus. Yog hais tias tus screws tsis pub nws tus kheej, nws yuav ua rau tho nres. Yog li ntawd, nws yog tej yam uas tus ntsia hlau uas punched tawm yuav qhia tau qee yam tsis tsim nyog, xws li cov npe ntawm ib nrab.
3. Nws tseem ua tau tias txiab hauv lub cav ntsia hlau khiav ceev dhau. Qhov ntev ntawm qhov ntsia hlau tsis zoo li qub. Lub screws tawm tuaj yeej tsis zoo li qub. Lub taub hau yog qhov tseem ceeb.
4. Nws kuj yog tau hais tias lub hau ntswj hauv lub tshuab ntsia hlau yog ceev. Qhov laj thawj no kuj tseem tuaj yeem ua rau cov khoom hluav taws xob tsis zoo