Bayan sashin niƙa, slotting da chamfering, akwai ƙurar ƙura a kan kushin birki.Domin samun mafi kyawun fenti ko foda a saman, muna buƙatar tsaftace ƙurar ƙura.Saboda haka, mu musamman tsara da surface tsaftacewa inji, wanda gama da nika inji da shafi line.A kayan aiki da ake amfani da tsaftacewa tsari na karfe baya surface na mota birki kushin, wanda zai iya saduwa da bukatun tsaftacewa surface tsatsa da hadawan abu da iskar shaka.Yana iya ci gaba da ciyarwa da sauke kushin birki.Hakanan yana da halaye na aiki mai dacewa da ingantaccen aiki.
Injin ya haɗa da firam, splint, injin tsaftacewa, injin isar da kayan aiki da injin tsotsa ƙura.Tsarin tsaftacewa ya haɗa da tushe na mota, farantin tallafin tebur mai zamiya mai nau'in V, injin ɗagawa na z-axis wanda za'a iya ɗaga sama da ƙasa, kuma ana iya motsa kusurwar hagu da dama.Kowane bangare na na'urar tsotsa kura tana da tashar tsotsa ƙura daban.
Haɗa ta hanyar bel ɗin mai ɗaukar kaya, ana iya aika mashin ɗin birki ta atomatik cikin injin mai tsabta, bayan tsaftacewa da gogewa sosai, zai shiga layin suturar feshin.Wannan kayan aikin ya dace musamman don motar fasinja da fasinjojin abin hawa na kasuwanci.