Well, not always, but usually. I started out with garment sewing with my mom, so it is automatic to wash the fabric first to remove the sizing, excess dyes, and take up any shrinkage (because if you don’t, your garment may not fit after the first washing). When fabric is woven, printed, or otherwise manipulated, it passes through rollers and machinery before being finally placed on a bolt, in a semi-continuous process. This stretches the fibres, so prewashing your fabrics will relax the stretch.
I also find that fusible interfacing works better for me when I prewash, it just seems to stick better (and yes, I often prewash my interfacing too). I will tell you a little secret–for solids I rarely prewash.
However, I also like to be gentle with my fabrics. Of course quilting cotton is expensive, so I have developed a method for hand-washing my fabrics. This minimizes the strings, wrinkles, and wonkiness that can result from using an automatic washer.
First, I sort my fabrics by colour. If I am washing several fabrics, I start with the lightest and work up to darker fabrics, using the same water for successive batches. I use a very small amount of a gentle detergent (I use a phosphate-free one) in room temperature water in a white bucket (white so I can see if the dye is running badly). In my second bucket, I use cold water, sometimes I add a couple of tablespoons of homemade liquid starch.
First I swish the fabrics in the wash water, and leave them to soak for 5 minutes. I wring out by hand, and throw into the rinse bucket. Similarly, a few swishes, a bit of soaking, then wring out. I lay the fabrics flat on a bath towel, and roll it up to squeeze out more water, then hang to dry (on an indoor drying rack). Once dry, I iron, and they’re ready to use.
This technique works for me and it’s not too labour intensive. So tell me, do you prewash? Have you tried making quilts both ways? Any experience with mixing washed and unwashed fabrics?
Linking up to Sew Cute Tuesday hosted by ChrissieD at Blossom Heart Quilts.