I've done the same thing, except I didn't weight it down. I've also intentionally left it in the trunk of my car in the summer heat and it went back to normal. You can also use a blow dryer to heat it up, and put heavy stuff on it, or put a towel on top of it and a towel under it, using steam, steam the heck out of it, once it's good and hot and steamy, keep it flat and it should go back.

If that doesn't work, before you decide to throw it away, see if you can cut off a portion instead of just throwing the entire thing away. There has to be a part of it that isn't ruined, and cut the unwarped part off and make yourself a smaller board.

Gayle Bong---I have had that happen to a ruler.

I tried all those tricks, and finally cut it, and made a smaller mat out of the unwarped part..
Barri

The only person I know of who was successful in recovering a warped mat lived in AZ. She laid her matt out in the sun and after it got supple, put heavy things on it. It flattened. Doesn't get hot enough here in MN (I tried).

Thanks ladies! I'm going to cut it down and then go purchase another..........

I have tryed most of the above, nothing worked for me. I think a lot depends on what quality of board you have, I'd contact your manufacture and ask what they would recomend. Mine recomended a new matt! LOL mine was only about 20 years old.

We sort of un-warped one here in Georgia. Put it on the white concrete during the heat of a summer day, weighted it down with heavy textbooks after it got hot. It's not perfect, but it's usable. JoAnn sales and coupons are the best fix! It's amazing how little time it takes to warp one.

It doesn't take much to warp one of those mats either. I set a coffee cup on mine for just a couple of minutes and had a warp, I just smoothed on it for a while and it went flat again, I was so happy. Don't want to do that again as they are an investment.

The mat is an Olfa......I'm amazed that with the ironing white board from JoAnn's on top of the Olfa that it warped.

Oh well......live and learn!

Thanks again ladies~

This happened to a good friend of mine after she purchased it from a quilt shop!!!!! No coupon, full price, large Olfa mat. It molded to the shape of her trunk and she tried everything and couldn't get it flat.