Is This doable
 

Am I missing a step. I have quite a collection of mostly fat quarter (black & white). I'm thinking about using them as a backing. I will cut them into 18 inch squares, then nine patches and so on till it's big enough to make a backing. Is it that simple.

Sounds like a good plan!

Sounds doable to me. You could even cut them 18 x 21 or 22 (depending on FQ size) and use pretty much all of the fabric.

I've done that with smaller squares, 10" or so, but also made rectangles out of FQs, 1/2 yd pieces. I usually trim them all the same size and stagger them like brickwork. Sometimes I do the whole back that way. Other times I add a pieced section of brickwork between yardage.

I've been making double sided quilts for at least 20 years, maybe longer. Go for it, you'll love it.

black and white always makes for a stunning quilt. Anxious to see when finished.

Sounds nice. Go for it!

Problem I have had with pieced backings is getting it lined up straight. I use the Sharon Schamber method of basting. Maybe I will have to try spray basting.

a great idea, and I would use the whole fat quarter,as quiltsRfun suggested!

It is doable but I usually look at what is going to be the best fit for the back of the quilt. Those 4" your are trimming off might just help you extra yardage you need for a backing. My next quilt might just be this quilt that needs black & white prints called Diamond Heads by Cozy Quilt shop:
http://www.ebay.com/itm/172010101311...%3AMEBIDX%3AIT

Pieced backs are lovely and especially so when it makes for a reversible quilt. One solution to getting them lined up would be to find the center of both the front and back and hand baste them across at that point. Then proceed to baste with favored method. I use Elmer's School glue. Therefore, I would glue the batting to either the front or back before basting through the center to line them up.

Thank you. I kind of knew about the centering thing, just totally forgot about it. The reason I chose the bigger blocks was to try to avoid seams meeting on my 12 inch block quilt. But the brick work idea is a better use of my fabric. Thank you all for all the ideas.

It seems to me that you will have two quilts in one when you are finished. I wonder if having a seam or two match up will cause a real problem when quilting. I don't think it would be like having ALL your seams match up. Be sure to post pictures when you have finished.

I piece all of my backs. I use what is in my stash. My stash is out of control and I am trying to avoid buying any fabric. I usually make a back that is not a straight design. Put something purposely off center. That way when it doesn't end up perfectly straight on the back of your quilt no one can tell. Also if you do all the same size block when you trim your edges it will show. I often loosely copy a simple modern quilt for my back. google quilt backs or modern quilts for ideas.

Here's a trick I use to get my backing straight with the front when I glue baste but it would work with pinning and thread basting as well.

First piece your back making sure it is larger than the front but a few inches all around. Pick a seam that is going to be your reference point somewhere near the middle third of the backing. Tape drinking straws or unsharpened pencils along the seam on the right side of the fabric. I use painters tape to do this. When I glue baste I do this after I glue the batting onto the backing. If you were pin or thread basting you would do it before you sandwiched the three layers together.

Next, with right side of the backing facing down, layer your top on (or if you are pin or thread basting your batting, and top). You will be able to feel where the seam is thanks to the straws/pencils. Match this up with a straight reference point on the front of your quilt. Voila! your back and front are straight together and the quilting, especially if you use straight line quilting will look much better.

That's a splendid idea and something I'll consider in the future...

Thanks for all the great tips.