Monday, November 7, 2011

A felting primer for hand knits (wet felting)

Felting knitting, or "what's in a name?"
Some call it fulling, and that's probably the most technically correct. Some call it "boiled wool," and you can certainly boil it, but you don't have to. I think most people call it felting, so I will too.

So, what IS felting?
This post is about wet felting.  Wet felting happens when wool is subjected to three factors simultaneously.  First, there must be WETTING; second, TEMPERATURE CHANGE and third, AGITATION.  When all three of these things happen at once, woolen fabric will shrink substantially, becoming both thicker and smaller. (There is another kind of felting done dry which is worked with barbed needles.  This is called needle felting, but it is not covered in today's post.)

Why felt?
Felting has two sides to its nature: the utility aspect, and beauty inherent in such a dense fabric.
Felt is as close to a miracle fiber as you can make outside of a lab.  It is somewhat rain-proof, somewhat wind-proof, immensely warm and very hard-wearing--nomads in some of the world's coldest places live in felt huts, dress themselves in felted hats and boots and use felt to ride their horses. Closer to home, my kids have worn felted mittens here in Wisconsin for years: here is the same pair as shown in the opening illustration after they were worn for two years by a little boy for snowball fights, sledding and all-around tom-foolery.  An unfelted mitten would never have survived, but these are tucked away safe, waiting for another little kid who needs bomb-proof mittens.

< threadjack >
If you want to make the mittens illustrated in this post, they are available in a couple of ways:
For recipe (free)  click here
For the pattern ($3.25, child's XS-XL) you can
*Click through to the pattern page
*Click through to the project page 
*or buy the pattern now

<  / threadjack >
beauty of the fabric
However, utility knits aren't the only reason to felt.  Felting is inherent beautiful with a soft, lush look.  The stitches lose definition and meld together, the surface becomes matte. Here is a peek at the fabric of a felted cushion.  The density of the fabric not only makes it wear hard, but makes it almost luminous--the depth of the fabric reacts with light differently than a thinner or smoother or shinier fabric would, the colors seem more saturated.  Of all the cushions we have in the house, this is the one that people find themselves holding and carrying around from place to place.

Felting is irreversible
Felting is an irreversible process.  Once felted, a hand knit garment cannot be unraveled. The yarn has stuck to itself and congealed into a solid mass. This irreversibility has both downside and upside.
  • On the downside, that beautiful hand knit which went into the washing machine by accident has been ruined, yes.  Nothing--not vinegar, not yogurt, not shampoo, not conditioner--can bring it back to its pre-felted state.  
  • On the upside, it is the very irreversibility of the process that makes felted items so hard-wearing. Felted knitting can be cut, sewn and shaped. It will not unravel, so a felted sweater can have a long and lovely second act cut up and sewn into cozy mittens and slippers. 

Felting is unpredictable
Besides being irreversible, felting is also unpredictable.  Sometimes, felting occurs gradually and evenly across an entire garment.  More often, the process occurs suddenly and unevenly. Accordingly, felting garments to fit is something of a gamble. It is true that felted garments are commercially available--"boiled wool" jackets are a famous example. However, these garments are made from sheets of knitting which has been felted and then cut and sewn.  The jackets are not "boiled," the fabric is. For this reason, most knit-and-felt patterns are for bags, or mittens, or slippers: items where the fit isn't super-important.

Four ways to felt
The two main ways to felt are by hand, or using a washing machine.  Two other methods are by using a (clean!) toilet-plunger or by using a dryer. Whichever way you choose, however, consider turning the item inside out first, because the exposed side can get a bit roughed up by the process.

With hand-felting, you have more control over the project.  The mittens in the photo above were stopped from felting further at just the right time by having a paper pattern handy, against which the mittens were frequently compared as the size got nearer and nearer.

For larger projects, or for projects where fit is not so much of an issue, felting in the washing machine is a good choice.  Felting a large project by hand makes you realize the immense strength that the old washer-women must have had, to wrestle wet and heavy fabrics by hand.

hand felting
The basis of felting is that you knead and rub with the aid of dish-washing detergent—the suds act as a lubricant, making the rubbing easier.  (That's hand dishwashing detergent, not machine detergent!)

First, prepare a basin with cold water, and another with hot water, as hot as you can stand.  (Hint: wearing dishwashing gloves lets you use far hotter water than you could stand without them.) Wet the item to be felted in the hot water, then lift it out of the water and rub and knead a drop or two of dish detergent through it.  Hold one part of the item in one hand and the other part in the other hand, and rub the item on itself, changing your grip frequently to bring new parts into the process. Rubbing evenly all over gets the best all-over felting. 

Dunk the item into the hot water again, and begin to wash the detergent out, then abruptly dunk the item in the cold water and continue kneading and rubbing.  Again lift the item out of the water, add a drop or two of detergent, then agitate and rub for a while. Continue in the manner, alternating sudsy kneading under hot and cold shocks until the item is the size you want. The felting and shrinking usually occurs when the cold water shocks the wool, although it sometimes occurs on a hot-water shock.

Sometimes glove fingers or mitten thumbs fingers might try and felt shut.  Keep a wooden-spoon handle or chopstick handy to poke apart unwanted interior felting.

If you want to try boiling, dunk the project into a pot of boiling water , stir it with a wooden spoon, dunk it back in the cold water and do the soap and agitation cold.  Repeat. One thing about boiling is that dyes used on woolens aren't always benign. Be sure to wash the pot very thoroughly afterwards, and use only a stainless steel pot to avoid unwanted interaction of the pot-metal with the dyes. 

However you do it, this process sometimes takes a LOT longer than you think, and you might have to replace the hot water with fresh if it gets too cool.  Depending on the color and type of wool, it has taken me as long as 20 minutes of constant agitation and temperature shocks to felt one measly mitten.  Other times, however, the process takes place so fast you can hardly see it happening.  If it is taking a while, take heart: although you may doubt it while you are wrestling away, as long as the item was knit with ordinary wool (NOT SUPERWASH!!!) it will eventually shrink. 

When the item is the size you want, stop rubbing.  Let the item come to room temperature, then gently rinse out the suds in fresh lukewarm water, then lay flat to dry out of the sun. 

washing machine felting: 
top loaders vs. front loaders
The easiest machine for felting in an old-fashioned top loader you can stop in mid cycle. This lets you haul out the wet item to test the size as the process progresses.  These old top-loaders also let you re-position stuff--sometimes items to be felted get folded on themselves during the spin cycle, and the marks left behind can be hard to get rid of. Another advantage is that, on most top-loaders, you can change the cycle with the twist of a dial, easily switching from wash to rinse to spin. Yet another advantage is that you can keep cleaning the lint screen if your project sheds. Top loaders do have one important downside, though: believe it or not, a washing machine agitator can break your arm. Be sure the machine is turned OFF before you reach in. 

Felting can also be done with a front-loader.  These machines lock and it is often difficult to change the pre-set program once its started, so to get around this, choose the shortest cycle. This lets you keep checking the size after each run-through.

machine how-to
The principles of felting are the same whether by hand or machine: lots of temperature changes, lots of agitation. Each machine has different settings, so look for a heavy-duty cycle (lots of agitation) with abrupt temperature changes (hot wash followed by cold rinse, or vice versa).  Unless the item is massive, it probably makes more sense to toss your felting in with a compatible load (or loads!) you were planning to run anyway. 

Some people prefer to run the item through the washer in a mesh bag or a pillow case. This does help catch the fibers from the wool, but has the downside that the fibers may be re-deposited on the surface of the item. Nevertheless, if your machine is elderly or likely to get clogged from a particularly wooly project, a bag is probably a good idea. 

If you are using a method where you can't get at the item during the felting process (the item is in a pillow case or a mesh bag, or if you are using a front loader which can't be stopped) you might want to consider stuffing the project loosely with a small rag.  This helps keep the item from folding over on itself inside the bag or during the spin cycle: folding can leave crease marks. For small items, a loose stuffing can also help prevent the item from starting to felt to itself.

Yet another trick: a toilet plunger
A toilet plunger offers yet another way to felt.  Yes, this sounds d.i.s.g.u.s.t.i.n.g, and so it would be if you used the same plunger for felting as for your toilet.  Yuk.  Don't do that. Buy a brand new toilet plunger and hide it away when you're not felting.

Fill the tub with hot water, and the bathroom sink with cold water and have at it with the plunger. This is more work that machine felting but less work than hand-felting.  Plus, unlike front-loader felting, with a toilet plunger, you can stop at any time to check the project. 

A final trick: dryer felting
You can also felt hand knits, sort of, in a dryer.  You put in the wet item (turn it inside out) and the dryer does the temperature change and agitation part.  The upside of this is that you can stop the dryer at any time and have a look, the downside is that it often takes multiple wetting/drying cycles to get a moderate amount of felting:  the temperature change is gradual, and the agitation less than if the item were in water. This will eventually work, but it's slow, and even slower if you put it into a bag or pillow case. 

Washing felted items
Just because something is felted doesn't mean it won't shrink if you wash it again.  The upside is that if the item is still too big, you can re-felt it.  But if you'd like the felted item to retain its size, wash it the same way you would wash all woolens: cool water, no agitation, no temperature shocks, and no dryer. On the other hand, felt doesn't really seem to get very dirty--to my recollection, I've never actually had to wash a pair of felted mittens.

There is something about felted wool which pairs well with embroidery.  Below are some "alien eyeball" mittens (also much worn) which were embroidered after felting with a sharp needle and woolen (called "tapestry") yarn.  Although there are firmly-knit exceptions, like Swedish embroidered twined knitting, knitting generally doesn't play well with embroidery because the embroidery sinks into the stitches.  However, felted knitting has no such problem. 

(These are child's size large from the kid-mitt pattern, just somewhat misshapen, you know, from long wear.)

--Good knitting, TK
You have been reading TECHknitting on "felting knitting."