I'd agree with previous posts - thinner paper curls more, heavier paper less, but I've never not had it straighten up totally after an hour under a dictionary, and that's not always necessary. Sometimes if I'm trying to stamp on it, I'll use low-tack tape to keep it flat on my stamping surface (so I can stamp accurately) before attaching it to the base. Tags curl too
, as you can see in the photos in the tutorial in Resources
For this card I had to tape the paper down to stamp on it, but it was perfectly flat when it came to adhering it to the base: http://www.splitcoaststampers.com/ga...&ppuser=133118
, and it's very light card that I got by mistake.