just trace out the triangle on an old piece of cloth or a piece of scrap cloth and make it a little longer on the back side, then take the extra length and glue it to the back side of the triangle. Then when you rack the balls the cloth is under the rack where you place the balls. Repeated dropping of balls especially on ball return tables wears this area of the table fast. This cloth takes most of the beating, as you roll the rack forward the rack cloth comes out. This is probably one of the most worthwhile efforts a table owner can do to extend the life of the cloth and avoid cross corner banking problems as the cloth at some locations is very bad causing ball waving.