A boring apparatus comprising: a feed screw mounted to rotate about its axis, a cutting head and a boring bar, each coaxially mounted on the feed screw by a feed nut, whereby rotation of the feed nut by one full rotation relative to the feed screw causes movement of the cutting head by a distance P along the axis, the feed screw having two ends, a distal end and a proximal end, the proximal end having a first planetary gear assembly, a tubular drive shaft coaxially mounted around the boring bar, operably connected to the boring bar to rotate the boring bar about its axis and to permit relative axial movement between the boring bar and the tubular drive shaft, the tubular drive shaft having two ends, a distal end and a proximal end having a second planetary gear assembly, situated adjacent to, and distally situated with respect to, the first planetary gear assembly, a drive motor operably connected to rotate the tubular drive shaft, boring bar and cutting head at a cutting rotation velocity, from zero up to a maximum cutting rotation velocity, about the axis of the feed screw wherein the carriers of the planetary gears (18, 21) of the first and second planetary gear assemblies are rigidly interconnected, whereby the carriers rotate in unison about the axis of the feed screw, characterised in that, each of the first and second planetary gear assemblies has a central sun gear (19, 22), around which one or more planetary gears (18, 19, 21) orbit, and an annular ring gear (20, 23), which surrounds both the sun gear (19, 22) and the one or more planetary gears (18, 19, 21), wherein the boring apparatus further comprises a primary feed motor, which is operably connected to, and capable of driving, a primary feed drive shaft that is operably geared to a face of a ring gear of a first one of the planetary gear assemblies, whereby the first one of the planetary gear assemblies is rotatably drivable by the primary feed motor, and wherein the ring gear of a second one of the planetary gear assemblies is configured to be held with zero rotational speed or to be rotatable about the axis of the feed screw independently of rotation of the ring gear of the first one of the planetary gear assemblies. a feed screw mounted to rotate about its axis, a cutting head and a boring bar, each coaxially mounted on the feed screw by a feed nut, whereby rotation of the feed nut by one full rotation relative to the feed screw causes movement of the cutting head by a distance P along the axis, the feed screw having two ends, a distal end and a proximal end, the proximal end having a first planetary gear assembly, a tubular drive shaft coaxially mounted around the boring bar, operably connected to the boring bar to rotate the boring bar about its axis and to permit relative axial movement between the boring bar and the tubular drive shaft, the tubular drive shaft having two ends, a distal end and a proximal end having a second planetary gear assembly, situated adjacent to, and distally situated with respect to, the first planetary gear assembly, a drive motor operably connected to rotate the tubular drive shaft, boring bar and cutting head at a cutting rotation velocity, from zero up to a maximum cutting rotation velocity, about the axis of the feed screw wherein the carriers of the planetary gears (18, 21) of the first and second planetary gear assemblies are rigidly interconnected, whereby the carriers rotate in unison about the axis of the feed screw, characterised in that, each of the first and second planetary gear assemblies has a central sun gear (19, 22), around which one or more planetary gears (18, 19, 21) orbit, and an annular ring gear (20, 23), which surrounds both the sun gear (19, 22) and the one or more planetary gears (18, 19, 21), wherein the boring apparatus further comprises a primary feed motor, which is operably connected to, and capable of driving, a primary feed drive shaft that is operably geared to a face of a ring gear of a first one of the planetary gear assemblies, whereby the first one of the planetary gear assemblies is rotatably drivable by the primary feed motor, and wherein the ring gear of a second one of the planetary gear assemblies is configured to be held with zero rotational speed or to be rotatable about the axis of the feed screw independently of rotation of the ring gear of the first one of the planetary gear assemblies.