I think the thing to consider is the size of the sheet and the size you want the quilt to be. My grandma, god rest her soul, used sheets but she would use a twin size sheet for a twin size quilt and therefore it was a little on the small size. So you may need to use a sheet a size larger than the bed the quilt is intended for (is this clear or muddled?) I agree that you would want 100% cotton, but then again if it is to be machine quilted it shouldn't be a problem. You can always try it once and make your own decision.