Guide to Needle Felting Cores; Testing Various Materials

This Needle felting is such a delightful and versatile craft! It allows us to create unique and intricate designs matting fibres together using a special barbed needle. In this tutorial, I will provide a guide to Needle Felting cores & testing various materials that are commonly used. See how each type has it’s own set of advantages and creative possibilities.

One important element in 3D needle felting & sculpture is the core, which serves as the foundation for the final creation. Choosing the proper core material is essential for achieving the desired shape, structure, and overall aesthetic.

What is a core for Needle Felting?

In needle felting, the term “needle felting core” typically refers to the central or foundational material that is used as the base for the needle felting process. The core serves as the structure (create bulk) onto which additional layers of wool or other fibres are felted using a barbed needle.

As you can imagine there is a wide variety of choices to use as core.

Which Felting Needle to use?

There are a wide variety of needles available for this craft of needle felting. They can be organized in a sectioned pin cushion or colour coded on the shaft.

Types of Felting Needles (terminology):

  1. Single-Needle Felting (Standard or Medium Gauge):
    • Purpose: These needles are the most common and versatile. They are used for general shaping, detailing, and joining pieces of wool together. The medium gauge needles are suitable for a wide range of felting tasks.
  2. Fine Gauge Needles:
    • Purpose: Fine gauge needles have thinner and closer-set barbs. They are ideal for fine detail work, creating intricate patterns, and refining the surface of your felted project. They are often used in the final stages to achieve a smoother finish.
  3. Coarse or Heavy Gauge Needles:
    • Purpose: Coarse needles have thicker and widely spaced barbs. They are used for quickly felting larger areas and for the initial stages of shaping when a more aggressive felting action is needed.
  4. Star or Twisted Needles:
    • Purpose: These needles have a twisted or star-shaped design with barbs all around. They are useful for quickly felting large areas and can help in creating textured surfaces. The multiple barbs enable efficient felting in various directions.
  5. Reverse or Forked Needles:
    • Purpose: These needles have barbs on both ends and are especially helpful for felting in tight spaces, such as when attaching limbs or smaller details to a felted sculpture. They allow for felting in two directions simultaneously.
  6. Spiral or Spiral/Twist Needles:
    • Purpose: These needles have a spiral or twisted design, which helps reduce resistance when penetrating the wool. They are useful for artists who prefer a smoother and easier felting experience.
  7. Blunt or Notched Needles:
    • Purpose: Blunt or notched needles are used for sculpting and shaping the wool without fully felting it. They create a more pronounced indentation or shape without compacting the fibers as much as standard felting needles.

Exploring Various Core Materials:

Polyester Fiberfill:

  • Advantages: Soft and lightweight, polyester fiberfill is a popular choice for beginners. It is readily available, easy to work with, and provides a good base for needle felting projects.
  • Creative Use: Ideal for crafting soft and cuddly animals, characters, or decorative items.

My test core balls:

(See video for more detailed desciption)

  1. 1 Yarn Wrapped Wool Sweater scraps
  2. Polyester Pillow stuffing
  3. Acrylic/Polyester Blanket strips
  4. Scrap blanket pieces wrapped in acrylic yarn
  5. Felted wool Sweater pieces
  6. Blanket strips over fabric scraps
  7. Combed Wool Fibres
  8. Polyester Quilt Batting strips
  9. Yarn wrapped sweater pieces
  10. Ball of wrapped yarn

These test pieces all felted quite well. They became dense and held well. There were a few tests that would not allow a needle (even a fine needle) to penetrate. It is best to try your small pieces before planning your project.

Material like wrapped yarn does give quite a dense form even before much poking with a needle and may work well when trying to achieve thin structure.

Understanding the different types of Wool Fibres:

Quite often Needle felting artists use core wool for the bulking of the form. Carded sliver and wool batt are both common types for core as well as spinning, and weaving. Here’s some notes:

  • Carded Sliver:
    • Carding: Carding is a mechanical process that aligns and separates wool fibers to create a continuous web of fibers. It involves using carding machines (drum carder) with wire brushes or teeth that comb and align the fibers.
  • Sliver: A sliver is a long, narrow bundle of parallel fibres that result from the carding process. It is a continuous strand of loosely aligned fibres ready for further processing or use. Sliver is essentially a long, narrow bundle of wool fibers that have been carded to align them in the same direction. This preparation makes the wool easier to work with in various fiber art applications.
  • Wool Batt: A batt is a thicker and broader sheet of fibers that is often produced by layering carded sliver or other prepared fibers. It is a flat, somewhat uniform mass of fibers ready for use in spinning, felting, or other textile projects. Wool batts are typically used in felting (needle felting, wet felting, or as a base for building up sculptural forms) and spinning.

Understanding The Different Wool Species:

The best type of wool for needle-felted sculptures as a core, often referred to as the “core wool,” is one that has specific characteristics ideal for needle felting. Generally, choose a wool that is coarse, has good felting properties, and holds its shape well. Here are some commonly used types of wool form different breeds of sheep for needle-felting cores:

  • Corriedale wool is a popular choice for needle felting. It has a good balance of softness and coarseness, making it easy to work with. It felts well and holds its shape, providing a solid foundation for building up details.
  • New Zealand Romney wool is another coarse wool known for it’s durability. It felts easily and works well as a core wool for 3D needle felting sculptures.
  • Bergschaf wool comes from a hardy European sheep breed. It has a coarse texture and is suitable for creating a firm core in needle-felted sculptures.
  • Blue faced Leicester (BFL) is often used for the outer layers of needle-felted sculptures due to its softness and luster, it can also be used as a core wool in combination with coarser wools. This helps add structure and firmness to the core while preserving the soft outer appearance.
  • Merino with Core: Some crafters prefer using a merino wool blend with a coarser core. The merino provides a soft outer layer, while the coarser core adds stability and structure to the sculpture.

Felted Fabric Sheets/Blanket:

  • Pre-cut felt sheets (blanket felt) are another convenient option, providing a flat and stable surface for needle felting. They are easy to shape and layer for added dimension.
  • Suitable also for creating flat or 2D needle felting projects like wall art, coasters, or embellishments.

Wire Armatures:

  • Wire armatures offer a sturdy and posable skeleton for needle felting projects. They are especially useful for creating sculptures and figurines with dynamic poses. Choosing a gauge of wire depends on your scale and also preference of ease of working.
  • Perfect for larger or more complex projects where structural integrity and flexibility are essential.

Wrapping some inexpensive pipe-cleaner will help anchor the core material.

In this test sculpture I used a the polyester quilt batting (long lengths & different directions) to wrap the armature. I wrapped quite densely and it does not fray as wool fibres may.

The batting does become quite sculpted with repeated poking with a coarse needle.

My ‘Test’ Felted Baby Bunny:

When choosing a core wool, consider the size and shape of your intended sculpture. Coarser wools work well for larger sculptures where a sturdy core is essential, while finer wools may be suitable for smaller, more delicate projects. In my rabbit the long strand wool I used was carded with the use of my own dog brushes to tangle the fibres even more for easier felting.

It’s worth experimenting with different wool types to find the combination that suits your specific needs and preferences. Remember; the success of needle felting depends not only on the type of wool but also on the felting needles and techniques used during the process. I find that continuing further with finer needles will give a smoother final texture.

Tip; mixing some shades & different colours together will give a more realistic representation of the animal fur. (more to come soon on fur-making)

Some wool fibres can be 25 microns in diameter or more, and your own hair is 50-100 microns thick. In comparison, merino wool fibres are typically 24 microns in diameter or smaller. Fine merino is less than 19.5 microns, superfine is less than 18.5 and ultra-fine merino is less than 15.

Happy Felting:

Choosing the right core material for your needle felting project is a crucial step in bringing your creative vision to life. Whether you opt for the softness of polyester fiberfill, the premade structure of foam shapes, the natural feel of wool roving, the versatility of wire armatures, the convenience of felt sheets/fabric, each material opens up a world of possibilities for expressing your artistic flair. Experimenting with different cores will not only enhance your needle felting skills but also add depth and character to your unique creations. Grab a kit, some felting wool and join the world of amazing needle felters! Happy felting!

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  1. Barb, you’re are so very artistically talented! I had no idea you could use polyester quilt batting as a core. Does wool felt to it as well as to actual wool? Thank you for your informative post.

    1. Thanks! I have found that the wool does work into the polyester core well. The key is not all polyester is the same, just like the wool. Once you find one that shapes fast and becomes dense the wools fibres will anchor in it well. The only possible issue is if you plan to use a reverse needle to full out fibres then they would be polyester. Butit would also depend on your depth. More needle felting to come!