Well, I can add my own tale of woe now.... after a happy 10+ hours of machining away, I am sufficiently confident I am not standing over the machine, so I'm the other side of the room when "Bang!" - no problem, just bust a cutter. So I go over, and sure enough the cutter's failed (not sure why, it was cutting as sweetly as you like). So I stop the machine, make a note of the program step, so i can restart in a civilised place instead of having to repeat hours of work, and for some reason I can't reset the controller to raise the spindle, it won't come out of "e-stop".
Reset machine. "DC 24v not present". Ubuggre. Machine = kauput.
I can turn everything on, the controller gets to sampling the 24v DC line & finds it dead, I can even turn the spindle brake on & off, and activate all the motor drives, but the controller of course won't send any signals. Arse.
The manual suggests testing the 24v regulator circuit, what it doesn't leave any hints about is what to do if it isn't being fed any juice....