jack pads new ideal

Been looking into replacing my old getting funky wood pads. Just back from a rally where two pads went under one set of duals so that they didn't lift off the ground and the other two pads were stacked under a jack. I'd have liked to have had 3 more pads! We were on grass and got maybe an inch of rain on our third day. We didn't sink in as the ground is pretty hard, but we picked up quite a bit of grass clippings on the three jacks without pads. looked like our jacks had grown a beard! The pads need to be large enough for a tire to sit fully up on, can't have hangover. And if the pads aren't big enough you don't get the reduced ground pressure to keep your jacks from sinking in. Figure it this way, an 8" diameter jack foot is 50 sq.in. an 18 inch sq pad is 324 sq.in. with just your jack pads you are exerting an average of 150 pounds per square inch if your full weight is on the jacks! with your 18" pads this is cut to an average under 22 pound per square inch! Larger pads are better!