in order to provide for the remote control and monitoring of a cutter support (48a) for pipe linings a body (11) is mounted, e.g. on skids (not shown). for transport through a lined pipe. A unit (32) is mounted on the body (11) so as to be adjustable longitudinally by a motor (44), angularly by a motor (37), and radially by a motor (56). The unit carries a motor (48) for the cutter (48a) and also a camera (49) trainable on the operative end of the cutter mounted on the support (48a) and also movable to a position (49a) where it is trained along the lined pipe. A second camera (41) is mounted in fixed position on the unit (32) substantially in the plane of the cutter.