Rewiring a mill to auto-start on power?

Hi hi All,

I have a bench mill, which uses a combo-start/stop button combo to power
on/power down the mill. I've got a nice relay system bult which can
apply power to the mill and this works. As the mill uses a start-wire
(probably a solonoid?) it will only activate the mill, until I press the
start button, and then it can be shutdown by turning the relay off (PC
side). This is a kind of nice safety feature, which prevents the spindle
starting up when the computer reboots, but it doesn't lend itself well
to CNC, where I have to manually race to press the button in the dwell
time of an M3! :)

I was wondering how I'd go about modding it, so that the computer can
_start_ it too? I'm guessing I don't wire it so that the start-solonoid
is always powered, do I?

Thanks,
Abby