When I lose center during a project, I must rehome my machine to reestablish center. This seems to take forever (maybe two minutes).
So to speed up things, I have embedded several ¾ inch copper pipe caps in my spoil board, wired back to the machine control (the probe input on the Gecko 540). I can now use a centering routing built into Mach 3, to locate center at any of those caps. One of these caps is located at the table center, and the others are at the bottom center, bottom left corner, and left center.
Much faster.
And yes, when skimming the spoilboard, my cutter can skim off the edges of the copper cap without a problem, also.

Angie