A friend of my DDs' is pregnant, and due in September. So I took out the baby colors I have to make a quilt. It happened that they are all flannels. Well, I have backed quilts with flannel before, but never pieced the tops of flannel. I merrily cut out all the pieces and started to sew them together. Low and behold, the flannel doesn't 'play' as well as the cottons I normally piece with. I had some that stretched, and when I was strip piecing for a rail fence block, strips that started out the same didn't end together...
:(

What suggestions do you have to help me in the process?

I don't have any advice but I have learned, on this forum, that flannels shrink like crazy after getting washed so it's a good idea to wash the fabric before cutting it.

One thing that I have done is the past when using fabrics that don't play by the rules is to pin, pin, pin and pin some more. I ease the longer fabric onto the smaller fabric by pinning at both ends, then at the center and then evenly along the length of the seam. I hope this makes sense to you.

Prewash. Prewash. Prewash.

Actually, some people do wash their flannels more than once before cutting them to get as much shrinkage out of them as possible.

If you are cutting strips, I think it would be helpful to cut them on the way that has less stretch - usually the lengthwise grain that is parallel to the selvage.

So when you sew the strips together, they might "play" better together.

Also, depending on your flannel, make wider/deeper seams than 1/4 inch.

The lighter/flimsier the flannel, the deeper the seam. Minimizes the chance of the seams pulling apart.

walking foot, walking foot, walking foot :-)

I agree with this advice.....prewash and walking foot

My very first quilt was an around the world with 3" flannel blocks!!! I did wash it a few times first, and then to deal with the stretching, a slow laborious project before I had a walking foot, was stitch half way down the block, take out, and stitch down the other side, meeting n the middle. What a job, but, the corners matched and the quilt is 7 years old and washed a zillion times and still in every day use.

Same as above. Always pre-wash flannels. I don't usually pre-wash my cottons but always the flannels because they do not play well together.

I agree with all this advice especially the wider seams as I have had a few come apart after washing before I did wider seams.

Try starching them heavily. Since you've already cut everything I don't think you can wash it now....so starch it and that will help with the moving of the fabric. And I mean HEAVY - many sprays and ironings. And don't push the fabric around - spray, then set the iron down on the square, then starch, set the iron down, repeat. Till its stiff. Then be VERY careful sewing.

That's what I was going to say, "Starch, Starch, and more Starch until it's stiff."