saw 121 as shown in revolutions per minute may optionally be provided in addition a tool advancing control is provided to control the speed of advance of the drill bit 151 into the casing 200 u2032 and the blade 121 of the band saw 120 into the casing 200 u2032 corresponding positioning devices 127 shown in fig1 and 156 shown in fig4 are provided for the band saw 121 and the drill assembly 150 these positioning devices 126 156 in one aspect represent telescoping hydraulic cylinders these devices permit the drill bit 151 of the drill assembly 150 and the blade 121 of the band saw 120 to be independently selectively advanced towards the casing 200 u2032 during the respective drilling and cutting operations and then withdrawn in addition both the band saw 120 and the drill assembly 150 optionally include pressure sensors to determine the amount of pressure placed upon the casing by the rotating drill bit 151 or the rotating saw blade 121 gauges may be provided at the control panel 125 indicating pressures on the drill bit 151 or the rotating saw blade 121 for example core heads and saw blades provided by mirage tool co ltd u k and core heads from alf i larsen norway may be used the clamp assembly 130 also has controls that are located on the control panel 125 for instance the clamp assembly 130 includes a panel mounted control which opens and closes the gate 135 located on the clamp assembly 130 optionally a gauge indicating pressure between the casing 200 u2032 and a clamp 140 may be provided and pressure of the clamps 140 a corresponding sensor is positioned on at.