MP (Mechanical polishing): hoʻohana maʻamau ʻia no ka papa oxidation, nā lua, a me nā ʻōpala ma ka ʻili o nā paipu kila. Aia kona ʻōlinolino a me kona hopena i ke ʻano o ke ʻano hana. Eia kekahi, ʻo ka polishing mechanical, ʻoiai he nani, hiki ke hōʻemi i ka pale ʻana i ka corrosion. No laila, i ka wā i hoʻohana ʻia i nā wahi corrosive, pono ka mālama passivation. Eia kekahi, he mau mea hoʻoliʻi pinepine ʻia ma luna o ka ʻili o nā paipu kila.