A bore head has a ring of boring teeth (1) around the edge to loosen the material and enable it to flow into the center for removal. Each tooth (1) has a number of cutting profiles (5) and rotates about an axis parallel to the boring axis. Each tooth is fitted into the head with a snap fit (4) and can be removed for replacement. The snap fitting mounting enables the operator to select tooth profiles to match the type of strata being bored. With the correct selection of tooth profile to boring head has a self clearing action for improved boring speed.
