Smashed patio table. My plan is to replace the top since the frame is still find. I want to inlay something that I can then adhere some nice ceramic tile I have leftover in my garage. My question is what would be the best rigid material about 1/4 inch thick that i can have cut to size (39" x 39") to rest within the frame and then adhere tile to for my outdoor patio table? Is plyboard my only option? I'm concerned about this just warping over time.