1. Ma tray a chingwe amakhala ndi ntchito yayikulu, yolimba kwambiri, yopepuka,
kapangidwe koyenera, kutsekemera kwamagetsi kwapamwamba, mtengo wotsika, moyo wautali,
kukana kwamphamvu kwa dzimbiri, zomangamanga zosavuta, mawaya osinthika, okhazikika
unsembe, maonekedwe okongola etc mbali.
2. Unsembe njira ya thireyi chingwe ndi kusintha. Iwo akhoza kuikidwa pamwamba
pamodzi ndi ndondomeko payipi, anakweza pakati pansi ndi girders, anaika pa
mkati ndi kunja kwa khoma, khoma la mzati, khoma la ngalande, mtsinje wa ngalande, nawonso akhoza kukhala
amaikidwa pa poyera woongoka positi kapena mpumulo pier.
3. Ma tray a chingwe amatha kuyikidwa molunjika, molunjika. Iwo akhoza kutembenuza ngodya,
kugawidwa molingana ndi mtengo wa "T" kapena mtanda, ukhoza kukulitsidwa, kukwezedwa, kusinthidwa mayendedwe.