My guild has one made with heavy ply 4x6". I asked DH to make me one. He suggested that I use my folding plastic "banquet" table. I made a sandwich of a sorry old mattress pad and a piece of uphostery canvas I got at a garage sale for almost nothing. On each side I made a wide, open ended sleeve. I threaded rope though the sleeve. Now when I put it over the folding table, I can tie it tightly and iron wide fabrics, even extra wide backing quite easily. Total cost, under $5.