Through the wringer

Before last week I had never used any superwash or washable wool for a project larger than a sock. My first experience with this category of yarn was last February when I knitted my first pair. I was surprised that the superwash Merino I used was not as springy on the machine as regular wool. The yarn was extremely soft and lovely, and when weighted properly, a pleasure to knit on the Passap DM80.

I am currently working on a project, the details of which I cannot yet reveal; but I can tell you that I am using another superwash merino.  I love this producer's yarns, but I'd never worked with the superwash line before. The end use of this project is extremely important to me (Isn't it always?) and so I decided to really put the yarn "through the wringer".

I set up the Passap for my climbing vine rib stitch pattern across needles 50< >50 / 50< >50 (between left needle 50 and right 50 on both beds). I then transferred for an embossed rib and knit 100 rows, same pattern and transition as used in my Harmony sweater. Markers were placed near each selvedge on row 50. I measured length and width, threw the swatch in the machine with similar colors and using regular detergent. I then machine dried the swatch with the rest of the wash. (I never ever treat my knitted objects this harshly. I usually use Soak or Eucalan and dry flat. I was experimenting this time.) I remeasured.

The results? The superwash swatch was 4.5% wider and 10% shorter after machine washing & machine drying. I am assuming that the swatch became wider after washing because I used weights* when knitting the swatch and I hadn't allowed the swatch to "relax" sufficiently after removing from it the knitting machine and before measuring. Though the fine grade Merino was soft before, the swatch was ever softer now. The yarn had also fulled somewhat.

Climbing vine and embossed ribs - the richness of the color isn't captured in this scan of the swatch.  The swatch lost none of the rich color after machine washing and drying.  

What I hadn't done in my test was keep a control swatch, one that hadn't been washed or dried. I needed to compare the "feel" of the swatch before and after. For my next experiment I knitted three swatches, a waffle-like tuck and rib pattern, and as before, over 100 stitches and 100 rows. The control remained untouched after knitting. The second swatch was machine washed and dried. The third was machine washed and air dried flat without blocking or pinning.

The washed swatches were softer than the unwashed swatch. Here are the resulting gauges:

Swatch #2

Swatch #3

Conclusion: Always treat your swatch as you will treat the finished garment before measuring for gauge. But you knew that. Right? ;)
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*I am aware that some people never use weights with a Passap. I generally use weights when doing tuck stitches, knitting yarn which lacks natural stretch and when knitting single bed.