Originally Posted by
m_c
You have to use a dial gauge to get the drill on centre in the X-axis movement. Stick the dial gauge to the chuck, then spin the chuck/dial gauge around the shank of the drill/holder, and jog the X axis until the drill is on centre. If the drill is at the wrong height, then there's an alignment issue with the turret.
If you have accurate homing, then you don't need a master tool. All the offsets are simply taken from the home position.
The master tool process is only needed if you're homing the machine manually, so you can take a test cut with the master tool, then enter that value to manually set the machine position, then have all subsequent tool offsets set from the master tool.
If the machine is running Mach3 via the parallel port, then to thread you need a single pulse. Originally there would likely of been some form of multiline sensor on the spindle, but it's of no use to the parallel port.