ʻO ke kiʻi gravity keʻano o ke kaʻinaʻana o ke kaʻina metala e hilinaʻi ana i ka ikaika o ka gravity. Eia nō naʻe, hoʻoikaika i ka ukiukiʻana,ʻo ia kahiʻano mea kūʻai aku ma keʻano heʻano hana kiʻi ma keʻano kūlohelohe o ka gravity. Ma kēia kaʻina,ʻaeʻia ka metala molten e kahe manuahi e kahe manuahi i loko o kahi pālolo, neʻe i loko o kahiʻano kiko'ī.
ʻO ka mea maʻamau i ka gravity casting, he hana maʻamau kēiaʻano hana no ka hoʻoleiʻana i nā'āpana nui a me nā'āpana likeʻole. Hiki iā ia ke hoʻopiha i ka mea hao e hoʻopiha i ka cevity āpau āpau, e hana ana i ka'āpana i makemakeʻia a iʻole ka hopena ma hope o ka hoʻomaha. Pēlā,ʻo ka mālamaʻana o ka mea kūʻai aku e hoʻopiʻi nuiʻia no ka hanaʻana i nā'āpana nui a me ka paʻakikī o nā wahi ma keʻano o ka neʻeʻana o ka molū.