When we first start sewing we are told that we need to prewash our fabrics before we cut them out. But to the novice this seems like nothing but delayed gratification – we want to have a go as quickly as possible. The same is true when we create our own knitted fabric for the first time. There is an urge to wear the item immediately rather than wait for it to dry. So what is all the fuss about when it comes to applying water to our fabrics?
Having grown up with handmade clothes, both knitted and sewn, I have no recollection of my mother prewashing fabric, or blocking my school cardigans. Of course she may have done so whilst I was at school, but I don’t remember it being mentioned when I was learning the craft. It wasn’t mentioned at home, or at my grandmother’s (who knitted the most cherished scrappy sweaters). It wasn’t even mentioned in home economics lessons. I had been knitting for 20ish years before I even attempted blocking. It was about the same time I began to see the benefits of prewashing fabrics as I moved into garment making.
So why do we prewash fabrics? Seasoned sewists are well aware of the need prewash. These leading ladies of the sewing machine know they should treat a fabric in the same manner they intend to treat the finished item. That means using your normal wash cycle for the fabric type and ironing the fabric if you are making an item that will be washed. We wash it to remove any potential shrinkage from the fibres. Otherwise all our hours of pattern tracing, cutting and construction will go to waste as the beautiful tunic we’ve been lusting over turns into an attractive, but entirely inappropriate crop top. This would, of course, be an exaggerated example, but shrinkage is real people! Many fabrics shrink by up to 10%. Some fabrics, like polyester, are unlikely to shrink but I am now in the habit of washing all my fabrics regardless rather than take the risk.
But why iron before cutting? The purpose of ironing is to smooth a fabric out. Whilst I rarely iron my ready to wear clothes as I hate my iron I do iron my prewashed fabrics. I have learned from experience that a creased fabric, even the slightest bit crinkled, can impact the final fit because it affects the accuracy of the cutting.
Now this all makes sense when sewing, but what about this blocking business? Surely once you’ve finished knitting you’re good to go? Not so my friends. Blocking your knitting gives it a polished finish. The yarn we knit with contains a certain amount of energy left over from the spinning process. Blocking effectively enables the yarn to chill out. The energy is taken out of the stitches, opening out lace work and evening tension. When knitting flat blocking evens out the edges making it easier to stitch together accurately. In all cases the result is a finished garment that drapes better, or a cushion cover that seems more professional.
Ultimately, as makers, we need to remember that water is our friend if we use it properly – if we fail to show it the courtesy is deserves it will play tricks with our makes.