Nemaumbirwo maviri esimbi yakacheneswa kana kuti yakatetepa uye ma retainer akagadzirwa nesimbi kana ma synthetic resins, ma bearing acho anozivikanwa nemigwagwa yawo yekunze yakagadzirwa nedenderedzwa zvichibvumira kusarongeka mukati me3° kutsauka pakati pemhete yemukati nemhete yekunze, kuitira kuti idzore kukanganisa kwe concentricity uye deflection.
