How to felt wool sweaters in the washing machine

With summer just around the corner, it’s time to pack away all those warm woolies and bring out light hot-weather clothing. So what do you do with those sweaters with little moth holes or stains, or with the ones that are stretched out or a bit shrunken? Put them in a big pile and get ready to make some awesome crafting/sewing material because they’re perfect for machine felting!

Say what? Felted or boiled wool is super easy to make and can be used for a gazillion crafts and sewing purposes! It’s all natural and, by upcycling unwanted garments, you avoid wasting fabric and spending money on new supplies!

Everybody’s accidentally shrunk a wool garment at some point, so don’t deny that you have. Boiled wool is basically wool that’s been shrunk til it can be shrunk no more. This process changes the fabric completely, giving it totally new properties. Felted wool is super thick and warm, so it’s great for cold-weather clothing. It doesn’t fray, so it’s fantastic for crafting with or creating embellishments with unfinished edges. It’s also waterproof, so a fantastic natural resource for those who want to avoid synthetic waterproof materials in cloth diapers or menstrual pads. And some people simply prefer its thick and rough texture to that of regular knit wool.

So today’s Learn to Machine Sew lesson is not actually about machine sewing, but about creating an excellent fabric to sew with! If you want to learn more about how to felt wool sweaters in the washing machine and how you can use this fantastic material, just read on!

Before we start, just a little note about terminology. In the sewing and crafting world, people always talk about “felting wool sweaters,” but that’s actually technically incorrect. Felting is the process of matting and pressing wool (or other) fibers to create a dense fabric. The felt, whether it be wool or acrylic, that you can buy in fabric or craft stores is the result of this type of processing of the fibers, which have not been worked in any way previously.

Boiled wool, on the other hand, is the dense, matted fabric made from fibers that have been previously knitted, crocheted, or woven in any other way, and aftwerwards shrunk. It would therefore be more correct to call this post “How to Boil Wool Sweaters,” but seeing as nearly everyone refers to this practice as “felting,” I will do so too.

Now that we have that out of the way, let’s talk about how to felt/boil wool. Basically all you need is water, heat and agitation and, lucky for us, a washing machine provides all three!

The first thing to do is make sure that the garment you wish to felt is 100% wool, or pretty close to that. The less wool content, the less the fabric will shrink. I wouldn’t go any lower than 80% wool content, so make sure to check the label! Remember that cashmere, mohair, merino and angora are also types of wool, so those work, too!

I love boiled wool, so from time to time I take a trip to my town’s weekly market, where there are tons of used clothing stands, and stock up on cheap wool sweaters, cardigans, vests and blankets. I skip the more expensive stands and go right to the 50 cent, €1 and sometimes the €2 ones. Remember that even the ugliest sweater can look pretty cool after boiling it, so don’t pass it up just because you don’t like it.

I then separate the sweaters by color for washing. My machine is small, so I can only do three or four sweaters at a time. A secret tool that I learned from my friend Irene (her post on felted wool is super informative!) is sticking tennis balls in with the sweaters to create more agitation. (Just don’t use balls that you plan on actually playing a game with later on, because they will get coated in wool fibers!) The basic rule is that the hotter the water and the more you beat up on the wool, the better it will shrink up.

Wash the load with a little bit of whatever detergent you have and the absolute hottest water and longest cycle that your machine has.

When you take the wool items out of the washing machine, you’ll see that they are considerably smaller (this process shrinks them up to 50%) and the fabric is matted and thick. Notice the difference in the fabric’s texture in the picture above. Before felting, you can see the actual knitted stitches and slight differences in the yarn’s color. Afterwards, you can no longer see the  stitches and the color and texture is a much more homogenous mass.

If your wool items look like the “after” picture, it’s time to dry them. I don’t have a clothes drier, so I just air dry mine. I suggest laying them out flat and smoothing them out, because whatever position they dry in is what they will continue to look like after drying. Also, if you use clothes pins to hang them up, there will forever be marks left behind from them. But if you do have a clothes drier, that’s even better, because you can dry them on the hottest setting possible, to make sure that they are indeed shrunk all the way.

If your wool items DON’T look like the “after” picture, put them in the wash again with the hottest and longest cycle and perhaps some more tennis balls. You don’t want to only partially felt the wool, because if it shrinks more after cutting and sewing it, you will be left with a deformed creation. (This has happened to me with some test cloth pads I’ve made and they do not look nice that way, even though they do work perfectly.)

If your wool item has button holes or other features, you might notice that some parts of it are deformed or felted to varying degrees. In the cardigan vest above, the armholes and neck are wavy because the thicker wool in those parts got less felted, and the button holes are wavy because the thread used to sew them did not shrink.

You can see the effect more in the buttonholes on this sweater. And notice the bump on the breast pocket? There was a logo embroidered on it and the thread didn’t shrink, so it got deformed.

Another nice thing about felting wool is that small imperfections, like little holes, pretty much disappear because of the matting of the fibers. I had to really look for the hole in the above sweater after felting it, because it had self-healed.

I just love the feeling of cutting boiled wool! It’s so thick, it has a good deal of substance, but it doesn’t fray at all, unlike a regular knit sweater. The picture above shows the cut edge of a felted wool sweater.

Because it doesn’t fray, felted wool sweater scraps are perfect for embellishments. You can cut your shape very accurately and trim off little bits as needed. Appliqueing felted wool is super easy because you just stitch shapes onto whatever cloth item you have without finishing off the edges. Another thing I love is rolling and twisting strips of felted wool into rosettes for embellishing clothes and accessories. But what I use boiled wool the most for is for the waterproof layer of cloth menstrual pads or cloth diaper covers. Believe it or not, the thick matted fibers prevent moisture from getting through it, making it perfect for waterproof items or for outerwear.

The picture above is from the practical project tutorial that goes with this lesson: gorgeous wool pillows with appliqué. And, just to prove how useful and versatile boiled wool is for crafting, sewing and creating in general, here are some projects that I’ve made with it!

Felted Wool Pillow with Leaf Appliqué

Eco Sponges

Toy Dogs in Altoids Tin Beds

No-Sew Felt Poinsettia

No-Sew Felt Snowflakes

Felt Christmas Tree Ornaments

No-Scratch Vintage Tile Coasters

DIY Chair Felt Pads

No-Scratch Doorstops from Rocks

winter hats from sweaters

kid’s leg warmers/adult’s arm warmers

choker-style neck accessory

Girl’s Headband

 

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This lesson on how to felt wool sweaters in the washing machine is part of the syllabus of Cucicucicoo’s beginner’s sewing course! Don’t forget to share pictures of your work on the Cucicucicoo Facebook page or other social media!