I found 24x36 coroplast at Home Depot for 5.75!!! Yay, now I can quit obsessing about trying to find it and just do it! I don't need a lot because my stash is not that big. I know I could have got them cheaper online, but I didn't want to buy a whole bunch. I bought three for now and can add more easily. Out of each 24x36 I can get 9 of the large cuts, or 6 large cuts and 12 of the small cuts.........or...?? I hope I can cut them with a box cutter, any suggestions? Thank you for your tuitorial!! Now my next project to obsess about is the big ironing board!