Abstract: A system for notching tubes to facilitate their joinder to other tubes or rods, in which a first portion of the notch is formed by a rotary cutting action extending progressively inwardly into the tube side wall and then outwardly in an arcuate path, and the second portion of the notch is formed by a plunging, shearing action which simultaneously punches the entire second portion of the notch out of the wall of the tube. The apparatus for forming each of the notches preferably includes a pair of die halves which together define a tube receiving passage intersected by a tool receiving passage, and a cutting tool positioned in the tool receiving passage. The tool is provided with a substantially axially extending rotary cutting edge for forming the first portion of the notch and a shearing edge for punching out the second portion of the notch when the tool is plunged through the wall of a tube positioned in the intersection of the tube and tool receiving passages.