I’m still in the process of constructing my canvas out of installation foam. I carved the foam and then used wood filler to smooth out the jagged edges and surfaces of the foam. I’m not in the process of sealing off the foam forms with gesso. This is a lot more labor intensive than I thought because each shape needs several coats of gesso and has to have an even coat. I’m encouraged by the result and am looking forward to adding additional dimensions when I paint over it with oils.