Great Article on Why Wool Yarn Felts

I saw this article in my Knitting Guild Newsletter and copied it here - so interesting.

The link above also takes you direct to the article.

Felt Making with Knits Ideas from Crystal Palace Yarns - Straw Into Gold

Why Does Wool Felt?

Recently I was reading various online sites about felting and about making felted purses and I was amazed to see a felted bay designer explaining that wool felts because it has a spiral structure and the coils get tangled and that makes felt.
This is an incorrect explanation of why wool felts, so I decided I should write a little about it.
As someone who has taught spinning and fiber classes since 1970 I have always explained felting this way:
Wool fibers have tiny microscopic scales along their surface. Some types of wool have larger scales than others. The types of wools that are coarser and smoother and have the highest sheen to them (such as Lincoln, Leicester, Wensleydale) have larger scales and reflect more light off their surface leading to the sheen. Finer wools (of which Merino is the main example) have much, much smaller scales and do not reflect light and have a more "matt" look to the surface of the yarn or finished knitting.
When wool fibers are shocked by temperature and rubbing the little scales lift up and as the fibers rub against each other they lock down on nearby fibers and form a tighter and tighter mass and form felt. Felt can be made from "just the fibers" unspun, or as many knitters are discovering, from knit pieces that are felted after knitting.
Many unhappy owners of fine wool sweaters have discovered felting by accident when a (usually well-meaning) mate or child dumps a wool sweater into the washing machine and out comes a much smaller, thicker sweater.
Superwash wool is a wool that has been treated by one of several processes or surface treatments that smoothes or "glues down" the little scales on the wool so that they do not lift up and lock down on neighboring fibers. Some treatments are more stern and really lock the fibers (with often a textile "glue" made from a nylon type solution that will dye similarly to the wool) and these treated wools can go through both a washer and a dryer. Most Machine Wash yarn labels, however, mean you can do a gentle wash cycle, but dry flat and NOT put in the dryer.
Remember, however, that machine washing will eventually soften the surface and lift fibers - even if the garment doesn't actually felt - and your handknits will look their best the longest if you do as much handwashing as possible, even on Machine Wash labeled yarns. I also recommend using a Lingerie Wash bag for washing machine washables (and many also use them for felting for a less fuzzy surface.)  See information here.
Here are some links to see the wool fiber under a microscope (I used to have a small microscope I took to classes I taught to show students wool, cotton, alpaca, etc. under magnification - great fun!)
This page shows microscopic views of various wools & a lot of information on wool:
http://www.rugreview.com/83wool.htm
Why wool shrinks - this article refers to the scales as "shingles" on the wool
http://www.glmerc.com/sleeping/wool.htm#shrink
Electron Microscopy of Wool - see page 6 of this PDF for a CLOSE View!
http://nvl.nist.gov/pub/nistpubs/jres/041/3/V41.N03.A07.pdf
Comparing Alpaca fibers and structure to wool
http://www.alpacas-4-sale.com/alpaca_fiber.htm
I've been experimenting with making felt using the printed colors of our Labrador (thick-thin spun yarn) and Iceland (smooth spun soft wool) and the interesting patterning and texture of the surface of printed colors adds an additional fun aspect to felting.
With both Labrador and Iceland being bulky you can knit up the piece for felting quickly on size 15 needles.
Here some before and after felting swatches using Labrador (with measurements):

Above knit on 15s in garter using Labrador wool stitch using color Picnic #7263 with a little stripe of solid  color #1219 fuchsia Iceland 6" x 5.5"		Above after felting* 4.5" x 4.5"
Above knit on 15s in rev Stst areas on 15s with Iceland in color "shadows" #7268 100% soft wool 5" x 5.5"		Above after felting* 4.5" x 4"

* For felting these - I put the pieces in the washing machine with a small load of bath towels and did a 5 minute wash cycle. Since they were not felted as much as I wanted, I put them in the dryer with the towels and took them out when the towels were about half dry (10-15 min.)
Susan Druding
SEE also photos of Iceland felted with Blippity yarn here.
Retail shops in the USA should contact CPY Wholesale for information on purchasing Crystal Palace Yarns.
email: cpyinfo -at- straw.com (change the -at- to @)

or write to:
Crystal Palace Yarns, 160 23rd Ave, Richmond, CA 94804
phone: 510-237-9988,  fax: 510-237-9809