You should be using cotton batting or several layers of an old flannel sheet. Regular poly batting can melt if ironed over and over. The cotton will become hard but the steam will go thru, that is why holes are in the bottom of a metal ironing boards. I have my Grandmother's wooden board, and my Mother's, and then my metal one that I got in 1962 when I got married. Since I have a summer cottage, I use Mother's there because I piece quilts there as well as work on curtains, do hems for my extended family, and do upholstery, pillows' etc. To me, my iron must steam, not shut off, and I always have a backup. Good luck with your board!