1 Algorithm based on impact on opinions over time - and Wikipedia. 2  Top ten most significant in history puts Jesus in the number one spot.  The list also includes Muhammad, Lincoln, Hitler and Shakespeare.
Plies vary in thickness from 1.4 mm to 4.3 mm. The number of plies depends on the thickness and grade of the sheet but at least three are required as the minimum odd number of plies. Roofing can use the thinner 5/8 (15 mm) plywood.
But I've found that bit manufacturers don't always agree on the size of bit required for a particular thickness of plywood. They don't even seem to agree on the actual thickness of plywood. For example, one bit manufacturer says Â½-inch plywood is actually 31/64 inch thick, while another says it's only 15/32 inch thick.