Abstract: A robot using a shielded-arc welding torch has an automatic tool change station in a small area of the work envelope. An effector adaptor is attached to the robot effector. The torch is secured to a tool adaptor. The tool adaptor body has a pair of semi-circular shells around it, with upper and lower mounting flanges on each of the shells and projecting in directions radially outward from the tool adaptor. A groove in the effector adaptor receives the upper flanges which are locked in the grooves by outward spring bias on the shells. A tool changer at the tool change station has a pair of grippers operable on the shells to squeeze them toward each other to remove the upper flanges from the effector adaptor groove, and remove the tool adaptor from the effector adaptor. A tool storage magazine has a retainer groove at each of multiple circularly-spaced tool receiving pockets.