hole that serve as a reference point for work holding tools, which helps support and stabilise the workpiece in a lathe, establish a starting point for larger holes, reducing the risk of the drill bit wandering and preventing deflection, standardiseeritud teljesihiline kooniline (võib olla ka kõverpindne) süvend, mida tehakse detaili otstes, tsentris, mida kasutatakse tooriku kohtkindlaks paigalduseks tööpingis (tavaliselt treipingis)
