I have made several string quilts also. The first one on fabric- left it on as a backing, that quilt (king sized) was quilted with poly batting and still was heavy. Second one was just strings, no fabric backing-no problems. The one I am working on now- I put on paper to try it. I don't particularly like doing the blocks on paper- but they do come off easy. tight stitches.......my strings are mostly 1" finished, so lots of stitching on a block. One thing I did notice- the paper rolled a bit and I pressed then from the paper side also. Not a big deal, just another step to remove the paper I'd guess.