Drilling tool to test trees and construction timber with and without cutting; has plane borer head with slender conical milling head, where wood shaving is heated from friction of milling head

摘要

The tool has a plane borer head with a slender conical milling head. The end diameter of the milling head cone is smaller than the rotating diameter of the plane borer head but larger than the shaft diameter of the tool. A wood shaving generated from the borer head is pulverised, carbonised or vaporised by the heat generated from friction for the higher working rotation rate at the surface of the milling head cone.