Cotton! The Standard of Quilting Fabric is 100% 'Quilt Shop' Quality Cotton.
Having been quilting for over 40 years (I started when I was ONE year old!!!), my first quilt, I used a mix of poly-cottons and cotton fabrics. The best fabric for quilting is definitly cotton. Especially, if you have used cottons on the top, DON'T use a blend for the backing. It will tend to cause puckers.
There are many people in the quilting world that believe you must pre-wash
Best suggestion for a beginner quilter is to purchase a 'charm pack'. A charm pack (created by Moda Fabrics) consists of (42) 5 inch squares from a line of coordinating fabrics. One charm pack makes a small baby sized quilt. Purchase more charm packs for a larger quilt.
of course, if you would prefer to make a simple quilt with fabrics or scraps that you already have, just cut your fabric pieces into 5 inch (or 6 inch) squares.
Lay out the squares on the floor or other large surface. Then sew either rows using a 1/4 inch seam allowance (not the 5/8" seam allowance you used when sewing clothing). Sew each row together - USING PINS - at each intersection to make sure the seams line up.
Then sew each of those rows together to make a complete quilt top.
There is a lot of controversy in the quilt world on whether you should pre-wash your fabric before using it a quilt. Everyone has their own opinion, and are usually quite adament that they are correct in their opinion.
I 'used' to do some pre-washing of fabric in the old days when before the industry got better at setting the colors. Anything that was a dark red, blue or black got pre-washed. Now days, that is not necessary as the fabrics produced now have the colors set. You will still find the those that HAVE to pre-wash. Read more about that in the the link below.
For more on WASHING FABRIC.
Cotton! Again, the answer is 'quilt shop quality'* 100% cotton.
Another somewhat popular choice for quilt backing is "minky", a soft, synthetic fabric that feels oh so 'slimey'. Yes, I said slimey. These quilts will slide right off of your chair or couch. We have a NO MINKY rule in our quilt shop!!! Just don't do it!
For decades quilters have opted for the convenience of a bed sheet as backing fabric for quilts. First, they are tightly woven; 180 threads per inch is considered a low thread count in bedding terms, but is more than double the common thread count of normal quilting fabric at 78 threads per square inch.
If using a sheet for the backing, PRE-WASH the sheet before giving it to your longarm quilter. Again, use a 100% cotton fabric, and consider the the higher the thread count, the nicer the backing will be.
*quilt shop quality - This is a higher quality fabric that is NOT found at Joann's or Wal-mart. Here is an article that talks about the difference. Chain Store vs Quilt Shop Fabric
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