Border help with a string quilt
 

I made a string quilt using muslin as my foundation. The quilt top has a bit of weight to it right now and I am planning on just using a flannel backing and not batting. If I add borders to my quilt top, and they don't have a foundation like the blocks, will it cause problems when quilting? I have never made a string quilt before and am quite clueless to blocks made with foundations. This quilt will just be a throw for July 4th.

Good question, don't know the answer but will watch for what the experts have to say. I am hoping to make a string quilt next.

I have made several foundation scrappy quilts, and while there is a difference in weight between the main part of the quilt and the non-foundation borders, with batting it has not been noticeable. In your case, with no batting, I think that a layer of flannel under the border would help to even out the thickness. Try it on a sample and see if you like it.

I would certainly recommend pre-shrinking any flannel used in the project.

I always use a poly batting on all my quilts. Warmth without the weight. I have never made a quilt with flannel or without a batting. I know someone will be along to answer your questions.

I have made a couple string quilts with muslin foundations. As long as you use batting for the entire quilt top, doesn't matter which kind you use, it will be fine. If you want to avoid excess crinkling, prewash the flannel since it can shrink more than most other battings do.