Reamer

A reamer that is rotated about a central axis and has, in a direction along the central axis, a tool front end and a tool rear end that is an end opposite to the tool front end,

• the reamer comprising a blade on a tool front end side, wherein
• the blade is made of a cemented carbide including metal carbide particles,
• the blade has on a circumferential surface:
• a chamfered cutting edge located on the tool front end side,
• a circumferential cutting edge contiguous to an end of the chamfered cutting edge on a tool rear end side, and
• a margin that is a surface contiguous to the circumferential cutting edge,
• a flute is formed at the circumferential surface of the blade,
• the circumferential cutting edge is formed at a ridgeline of the margin and the flute,
• the circumferential cutting edge includes a front end portion between a first position and a second position, the first position being an end on a chamfered cutting edge side, the second position having a distance of 1 mm from the first position in a direction of extension of the circumferential cutting edge, and
• as viewed from a direction passing through the central axis and the circumferential cutting edge and being orthogonal to the central axis, the circumferential cutting edge at the front end portion in an as-manufactured state does have a chipping that extends from the circumferential cutting edge to the margin and that is less than 10 μm when measured in a direction orthogonal to the direction of extension of the circumferential cutting edge.