Originally Posted by lakekids

A few years ago I did a demostration for my quilt group where I compared different types of batting and various combinations of pre-washed and non-prewashed fabric. All of the batting and fabric squares started out the same size.
I then layered and quilted them and washed/dried all the samples. This provided examples of the shrinkage and puckering encountered when using pre-washed vs non pre-washed fabric and different types of batting.