On my lathes I have written a little program to take them home minus 1/4", load tool 1, wait 4 seconds, and estop. On my Mills, in particular any bed Mills, I empty the spindle if a tool is in it, send the x to the middle of the travel (center the table over the frame) send the y & z to home minus 1/4" ( same as the lathes ,to be off the home switches), pause 4 seconds and m31 kill the drives, then flip the power. I have heard that leaving a mill at the extent of its x travel to the left or right for an extended period will stretch the iron and twist the frame, I don't know if there is any truth to it, but it seems logical since glass will develop swags from its own weight over time.