Drilling equipment and attachment means for the same

A ground drilling or cutting tool comprising a cutting element removably attached thereto by attachment means, and releasable retention means adapted to maintain attachment of the cutting element to the tool in the event that the attachment means fails,

• wherein said retention means comprises:
• a first surface on a side of the cutting element,
• a mounting recess on the cutting tool in which at least a portion of said cutting element locates,
• a second surface in a side of the mounting recess against which said first surface locates,
• channels in each of said first and second surfaces that align so as to cooperatively define a dowel hole when said first and second surfaces locate together,
• at least one dowel that locates in the dowel hole, and means for retaining the or each dowel within the dowel hole, and
• wherein the means for retaining the or each dowel comprises a recess in the or each dowel, for each dowel a bolt hole in the cutting tool extending substantially normal to and at least partially intersecting the dowel hole, for each bolt hole a bolt that locates in said bolt hole when and only when the recess in the dowel is aligned with the bolt hole, the bolt thereby securing the dowel in its dowel hole, and the dowel aiding to secure the cutting element to the cutting tool.