I will be working on my canopy soon. I've often wondered what other people use when they're sanding their canopies to support the inside. Some people use silly putty. I've thought of trying Play-Doh. But my go-to is always a piece of fresh bread. Cut off the crust and it's nice and soft and squishes right up in there and you can hold it and sand it without too much fear of it busting in half. Plus if you're hungry...