A couple of weeks ago, I posted the various steps involved in sewing my own canvas grocery bags. The result was six bags that looked like this:

A few days later I set out to dye the bags blue. I only did some of them, and what I discovered almost immediately after pulling them out of the (hot water) dye bath – before even drying them – was that the canvas had shrunk!

Now it’s not like I hadn’t considered that there might be some shrinkage (100% cotton + no prewash = some shrinking), but I didn’t realize there would be so much. What began as a bag with a 34″ circumference, 11 1/2″ height and 4 3/4″ gusset ended up as a bag with a 33″ circumference, 9″ height and 4″ gusset. In other words, I lost about an inch around, which wasn’t such a big deal, but I lost almost 6″ in height and depth. The post-dye bags have only about two-thirds of the volume of the pre-dye bags.

Lesson learned: always wash and dry your fabric before you sew something, even if you don’t think it will matter that much to the result, or you may be disappointed in the results.