I was able to pick up lots of plain brown, rather thin cardboard that are exactly the same size. I think they will hold fabric okay. My idea is to fold the fabric around the cardboard the way many of you do with the plastic holders that can be purchased. My question is how do I know whether they would be safe for long-term storage. Do you think that the fabric will change in color over time or disintegrate? The are used to store paper for long term storage, so do you think that makes them safe to use?