Originally Posted by
Prism99
I would not prewash because there are too many risks. Fabric shrinks differently when washed on its own compared to when it is first quilted to a batting and backing and then washed. Once quilted moderately, the batting takes over and prevents fabrics from shrinking outrageously; in other words, the batting stabilizes and moderates the shrinkage of the fabrics.
Risk is also added because you are dealing with both applique and embroidery. If the background fabric shrinks in a disproportionate way (old fabrics can shrink much more in one grainline direction than another, for example), the applique and embroidery may become distorted. If you wait until the background fabric has been quilted, the shapes and forms of the applique and embroidery will be preserved.
Some of the dyes may bleed when washed, but this can be controlled by the way you wash the finished quilt. The best way is to use Synthrapol (suspends unset dye particles in water so they don't settle into other fabrics) and ***lots*** of water to adequately dilute any dye bleeds. The easiest way to do t
his is in a top-loading washing machine. Fill with water, stop the machine to prevent machine agitation, hand agitate, advance the machine to spin to spin out the water, etc. Refill and re-spin as necessary until the water runs clear, then immediately lay out flat to dry (you do not want wet fabric to remain in contact with wet fabric).
Another advantage to quilting before washing is that the batting and backing layers add stability to what may be slightly fragile block fabrics.
Some recent fabrics will also shrink a lott more in one direction than another.
I would hand wash the blocks (with color catchers if you think some of the fabrics might be iffy for color fastness) and lay them on towels or a rack for drying. Then I would know - for sure - what I have to work with.
As far as batting controlling the behavior of the top and backing - it may - to my mind it' s like wearing a bra and control pantyhose to improve stability. Take them off and what do I get?
I prefer to know each component will be well behaved on its own.
Yes, you might end up with a mess. But I would rather have a mess at the beginning of the process than after I had spent hours and hours on a project.
I prefer a flat look - so I also shrink the battings that can be shrunk. Also, if you use a batting that does not shrink and one of the blocks had severe shrinkage, that might create an uneven look.
What you do might also depend on how you plan to hold the layers together. Tieing? Moderate quilting? Super dense quilting?
What kind of look do you want?