hi mary kay, thanks for responding,
i am using spectrum 96 glass, mostly 3mm but some are 2 mm thick, and i'm hammering pieces of clear coloured glass into 1/2 - 1" pieces that are being poured onto the shelf. thus some areas are 1 layer and some are multiple layers - obviously the glass often has uneven edges, but that has been consistent since i started to play with the glass this way
what do you mean by the footprint? do you mean the overall size?