Maximum size without the crumb tray

I was looking at a piece of tile sitting about that is 605mm long and 303 mm wide and 8mm thick. It looks like it might fit as a replacement for the crumb tray on thicker materials and certainly keep the laser off the very bottom of the machine, it also looks as if the gantry has enough room but just barely. I could or should just buy another piece of something, and of course, we know the laser cannot cut even as big as the crumb tray, but finding the largest shape that could be fit would be useful and 'I am wondering if anyone else has looked at this and uf there is enough variability in machines that the information would not be useful.

Search for margins and speed. Someone posted the areas that are allowed.

Bear in mind that margins get larger as you speed the job up. Also it’s all software controlled, so it’s subject to change at glowforge’s whim

As close as I can measure the distance between the gantry drops is 24" center to center but they do not make it all the way down and are some distance off the bottom that I cannot measure and then the tile is not sharp but rounded at the ends so at the last 1/8 inch less than the rest of the thickness. all very close and perhaps too close for consideration as perhaps a stone grinder I have could put a bigger bevel on the edges
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