I am trying to design an economical storage rack for kayaks. We'll be stacking the kayaks five high in the rack.

Presently I am looking for something to put on the floor of each storage slot to protect the hulls of the kayak. It has to be tough enough that a 50 pound kayak sliding over it won't destroy it, but most important it has to be inexpensive. The storage slots will be 32 inches wide by 20 feet long.

Recommendations?

tanstaafl.