How to Presoak Yarn before Dyeing It - dummies

How to Presoak Yarn before Dyeing It

With a few exceptions, all fibers, whether yarn, roving, or wool locks, should be presoaked before dyeing. This process is called wetting out the fiber, and it does two things: It removes any spinning oil or residual dirt that may inhibit dye uptake; and the Synthrapol breaks the surface tension of the water, making it easier to saturate the fiber completely before dyeing. This facilitates the bond between dye molecules and fiber.

Mix the presoak

  1. Add 1⁄2 teaspoon Synthrapol to a sink or basin of water.

    The temperature of the water should be room temperature to warm (95°F or 35°C) depending on the fiber and the process.

  2. Place the yarn or fiber in the presoak for a minimum of 30 minutes, sometimes more, depending on the fiber.

  3. After removing the fiber from the soak, gently extract the excess water.

    The spin cycle on your washing machine will spin out enough moisture after 1 minute to leave sufficient moisture in the fiber for dyeing. Make sure you turn off the water so you don’t add more water as you spin!

A salad spinner is a handy tool for spinning water out of small amounts of yarn or fiber. This is helpful if you are dyeing small sample skeins.

Keep these tips in mind when wetting out fiber:


  • To keep yarn skeins from tangling in the soak and during immersion dyeing, loop a piece of shoelace or string through all skeins. This leash will keep the skeins together and prevent them from tangling.

  • Handle wet roving very carefully. Never agitate wet roving as this may cause the fibers to felt (lock together). Always use two hands when lifting a hank of roving from the presoak, being sure to support the mass of fiber.

  • Wool locks are easier to handle if they are placed in a mesh laundry bag. Be careful not to agitate wool locks because they can also felt.

  • Certain fibers take longer to wet out. Silk generally needs to soak for at least an hour. Tightly twisted yarns and densely compressed top may also require more time.

Make an acid presoak for protein fibers

Some dye procedures require that you add acid to the presoak. Soaking fibers in an acid bath makes them receptive to the dyes by altering the fibers’ pH. This type of soak is used most often for direct application techniques. Soak fibers for at least 30 minutes before dyeing. Here’s how to make an acid presoak for 1 pound/454g of fiber:

  1. Use a 5-gallon plastic bucket with a lid. Add 6 tablespoons citric acid crystals and 2 teaspoons Synthrapol to 1 gallon room-temperature water (approximately 95°F/35°C).


  2. Store the acid soak for future dye projects by placing a tight lid on the bucket.

Create an alkaline presoak for cellulose fibers

When using direct-application technique on cellulose fibers, you must soak them in an alkaline presoak for 15 minutes prior to dyeing. This changes the alkalinity of the fibers so they will bond with the dye.

  1. Use a 5-gallon plastic bucket with a lid. Add 9 tablespoons of soda ash to 1 gallon warm water.


  2. When finished, place a tight-fitting lid on the bucket and store for future use.

Wear rubber glove and safety glasses when handling fibers in acid and alkaline soaks.