Composite boring cutter for small hole machining

The utility model discloses a composite boring cutter for small hole machining. The cutter comprises a handle, a composite cutter bar, a boring cutter and a milling cutter, wherein a cutter bar mounting hole is formed in the cutter handle; the composite cutter bar is in a step shape. the composite cutter bar comprises a first bar section, a second bar section, a third bar section and a fourth barsection; wherein the boring cutter is installed on the first rod section, a boring cutter installation hole is formed in the first rod section, a telescopic device is arranged in the boring cutter installation hole, the boring cutter is installed in the boring cutter installation hole through the telescopic device, and a two-blade milling cutter is arranged on the second rod section. The utility model has a simple structure, the boring cutter and the milling cutter are arranged on the composite cutter bar, machining of stepped planet holes and chamfers on a planet carrier can be completed at atime, the size precision