Kool-aid is a safe, easy and fun way to dye wool yarn. It requires no specialized equipment, and is safe enough to do with small children. Since it's actually food dye, you can even use your kitchen utensils without fear of contamination.
Choosing and Preparing the Yarn
To begin, you'll need a quantity of wool yarn. One of the great things about wool (and other animal fibers) is that it takes dye so easily and so beautifully. It's really pretty hard to get bad results. Plant fibers such as cotton can be more difficult to dye, requiring a dye solution with a base pH, so these instructions are for wool yarn only.
The yarn you choose can be thick or thin, natural or dyed. If you choose a previously dyed yarn, you should select one in a fairly light shade, since you want the Kool-aid color to show up. Overdyes often result in a more subtle, sophisticated color effect. For example, you could place light blue yarn into a yellow dye bath, and the resulting green will be different than if you simply placed natural white yarn in a green dye bath.
You should choose enough yarn to complete the project you have in mind, since it will be fairly difficult to duplicate the results exactly. If you think you might want to repeat a color in the future, then you'll need to make notes regarding exact quantities, times, and temperatures of everything you do.
If your yarn comes in a center-pull skein, you'll need to rewind it into a twisted skein or big loop. This allows the dye to come into contact will all parts of the yarn. (It's amazing how protected the yarn at the center of a ball can be!) You'll be handling the yarn a fair amount at rinse time, so tie the skein in several places to avoid having a snarled mess when you're done.
Pre-wet the yarn by soaking it in cool water for about 20 minutes, then squeezing it out. This allows for quicker, more even dye penetration. If you want to try for a mottled look, you can skip this step and start with dry yarn, but it will take longer for the dye to saturate the wool.
Choosing and Mixing the Dye
You'll also need some packets of unsweetened Kool-aid or other brand drink mix. The colors are fairly predictable - for red, try strawberry or cherry. For purple or blue, try grape or blue raspberry. For orange, try orange or tangerine. For green, try lemon-lime. For yellow, try lemonade. For other colors, try mixing different flavors together. Feel free to experiment with whatever flavors you can find - that's part of the fun. Some colors are harder to come by than others, and you may have to substitute or supplement with the kind of food coloring you can buy in the spice section at the market.
How many packets you need is largely a function of how much yarn you want to dye and how dark you want to dye it. For a sock or scarf-size amount of wool and a light to medium color, one or two packets should suffice. It's difficult to give exact formulas for the dyes, since so many variables besides amount of dye can affect the final result. The entire process is subject to a fair amount of trial-and-error, but that's where the fun is.
Remember that in almost all cases, you will be mixing the flavors in a much stronger concentration than you would to drink them. If you still can't get a color you like, try adding a few drops of food coloring. In general, when you mix the dye you want to have enough liquid to cover the yarn. If the yarn isn't completely immersed, the results will be mottled (a nice look, too), and having an excessive amount of liquid will dilute the color and waste the dye.
Finally, for best results, add about ¼ cup of white distilled vinegar per quart of water to make the pH of the solution acidic. This step isn't necessary, but wool accepts dye better under acidic conditions.
So, let's get started. I like to do this in my kitchen, but I do put down a layer of newspaper, plastic, paper towels, or whatever on the counter to minimize messes. Kool-aid may also stain fingers, mouths, and clothing, so wear clothes you don't care about.
The easiest, most child-friendly method is to empty a packet of Kool-aid into a large zip lock baggie, add about a quart of cold water, put in the yarn (enough for a scarf or socks), and seal the bag. You can then squeeze it around until it's well mixed and place it in the sun for several hours or all day if possible. The reason for placing it in the sun is that heat will help to set the dye, but it's not so hot that little fingers will get burned.
Allow the bag to cool as much as possible before taking the yarn out and rinsing it in cool water until the water runs clear. The reason for this is to avoid temperature shocking the yarn, which could result in some unwanted felting or shrinkage. Squeeze out the excess water and hang the yarn up to dry, out of direct sunlight if possible. This method will result in a single-color yarn, possibly with some variation in color saturation.
If you're not happy with the color, you can re-dye it with the same or another color, or use the dip-dye technique described below.
Cooking the mixture on the stovetop will set the dye better and more quickly than letting the sun cook it in a baggie. Simply place the dye mixture in a saucepan and add the yarn before turning on the heat. Heat the mixture to a gentle boil for 5 to 10 minutes, squeezing the yarn with a spoon or other implement to saturate it with dye. Be careful not to slosh the hot liquid on yourself.
Allow the mixture to cool to room temperature before removing the yarn and rinsing with cool water until it runs clear. As before, hang the yarn to dry.
The dip-dye method will allow you use two or more colors on the yarn. Keep in mind when you select your colors that they will overlap and form a third color for a short area. So, if you choose blue and yellow, you will also have a section of green where these two dyes blend.
Use a separate bowl or jar of the same height for each dye color. Add the dye, place the jars right next to each other, and put half the yarn in each jar. If the section of yarn that's out of the dye remains uncolored, you can "rotate" it part way through the process. Allow the yarn to sit in the dye for several hours, or until the dye is "exhausted." The dye bath is exhausted if all the dye adheres to the yarn, leaving virtually clear water behind.
If you like the color after only a short time, by all means remove the yarn from the dye and finish processing it. Remember that some of the color will rinse out, and the remaining color will probably dry a shade or two lighter.
After the dye bath, you can simply rinse the yarn in cool water and dry as before, or you can "cook" it to further set the color. To do this, place the yarn in a baking pan in the oven at 200 degrees for about 10 minutes. After removing the yarn from the oven, allow it to cool to room temperature before rinsing in cool water and drying.
Bourgeois, A. and E. Bourgeois. Fair Isle Sweaters Simplified. Bothell, WA: Martingale & Company, 2000. Has brief instructions and examples of Kool-aid dyeing on page 51.
Brown, R. The Weaving, Spinning, and Dyeing Book. New York: Alfred A. Knopf, 1978. Has general instructions on dyeing techniques.
Potter, C. and A. Xenakis. Handpaint Country. Sioux Falls, SD: XRX, Inc., 2002. Has general instructions on dyeing techniques.
Vickrey, A.E. The Art of Feltmaking: Basic Techniques for Making Jewelry, Miniatures, Dolls, Buttons, Wearables, Puppets, Masks, and Fine Art Pieces. New York: Watson-Guptill Publications, 1997. Has brief instructions for Kool-aid dyeing of both yarn and fleece on p. 22.