Why would a LArmer request ...
 

request that the backing be pre-washed, but not the quilt top or quilt top fabrics? Won't they then shrink at different rates? I am puzzled.</SPAN>

no idea dosent make sence to me

She probably assumes that the top is already washed.

I agree. I would assume that everything is prewashed. The original sizing is hard on needles, messing up her (or his) work.

I'm surprised. I prefer for it to be consistent. Both washed, or not washed. I use a new needle for every quilt.

What type of fabric was the backing? I know batiks from Sew Batik recommend washing with synthrapol before using. Extra dye and wax used in the process need to be removed.

Not sure, but I'm thinking her machine may have a problem with unwashed backings. The sizing and other finishes may cause her machine to skip.

With moderate quilting, shrinkage of all the fabrics in a quilt will be controlled by the batting. That is, with moderate quilting, a fabric will not be able to shrink more than the batting shrinks. The only time different shrinkage rates become a problem is when the quilting is far apart.

Fabrics when washed alone will shrink at their own rates, as there is nothing to stop them from shrinking to their max.

I would go with whatever the front is. I would also ask her/him directly why they want it pre-washed. It's better to know what their purpose is than ours.

I agree I would ask!!!

If you're wondering ... ask the LAQ'er!