Originally Posted by Prism99
Following is what I do when piecing flannel for a quilt. (I have not do this for a rag quilt, but I haven't made any rag quilts yet.)
This is the only time I prewash and dry, and I do it *twice* because flannel can shrink an incredible amount.
After washing, I starch the flannel heavily to restore body and to stabilize the fabric so it doesn't stretch and distort while cutting and piecing. My method is to mix a 1:1 solution of Sta-Flo liquid laundry starch and water, "paint" it onto the yardage with a large wall-painting brush, toss in dryer, then iron with steam. This makes for very accurate cutting and piecing of flannel. The flannel is about as stiff as thin cardstock (odd, but it works!).
Depending on the pattern and intended usage, I might increase the seam allowance of blocks to 1/2", as flannel can ravel.
As others have mentioned, stop and clean out your machine frequently (especially the bobbin area).
THANK YOU FOR SENDING THIS IN - IT SAVED ME ALOT OF TYPING!!!! It's what I needed to know before I made those first flannel quilts.
I will also add that the bulk of flannel itself makes it hard to get exact alignment of seams sometimes, and what you thought was pinned down "just right" as you sewed over the pins slooooowly can still come out slightly wonky. But for all the extras that go into flannel quilts, these are The Go To quilts for all three of my grandchildren - they have both quilting cotton quilts and flannel quilts but go to the flannels first.
Also, NEVER GO CHEAP ON FLANNEL. Get the best quality you can - as another poster said, "Ask me how I know this."