When I repaired my base foam, I notice a fair bit of damage was from the side rail of the metal base frame cutting vertically up through the outside bolster. These rails have a round on the edges but over time it isn't enough to prevent this relative thin rail from cutting, especially on that outside bolster as it takes the worst of it. I cut two strips of denim from the legs of a worn out pair of jeans and glued them onto the bottom of the foam in the red shaded areas with some 3M Super 77 for reinforcement. I noticed the new foam has some kind of woven reinforcement incorporated in the yellow shaded area, but I added the same fabric strips on the new foam as well before installation.
