GreyBeard's swim noodles are my #1 choice. The are stiff and weigh almost nothing. A couple years back, K mart had some end of season sales and the noodles were someting like $0.75 each.They had some planks of the stuff also for the same price. You can cut it with a sharp pocket knife. No crumbles to contend with. Glow fuel doesn't touch it. In fact it doesn't collect moisture at all, IEit isn't a sponge. I've used them for prop covers. the make a great cushion for standing your plane on it nose, the spinner sets into it nicely and the stuff doesn't skid around much. We use it at the field for covering the wing post pipes on our table's. Great stuff aa cheapprice.

Don