Fully Felted Felt

Instructions for making the best possible felt

To understand how to make great felt you must first understand the basis mechanisms of why wool felts and the different stages of feltmaking. Start by reading the following article to begin your journey in becoming a great feltmaker!

Structure of Felt

Felt is a non-woven fabric created by the entanglement of wool fibres. Only wool and other similar protein fibres like alpaca and mohair have felting properties. Wool fibres can felt together because their surface is made up of over-lapping scales which are smooth in one direction and rough in the other. When the wool is agitated in an environment with the right amount of heat, moisture, vibration and pressure the fibres can only move in one direction thereby causing them to permanently entangle. Heat and moisture swells the wool fibres, raising their surface scales and helps the fibre be more supple thereby enabling them to move easily and lock together into a compact mass.

Other factors are also important in making a felt, particularly the curliness or ‘crimp’ of the fibres, which makes them act like a corkscrew when they are vibrated. During felting they twist around each other and entangle. The fibres having the most crimp giving the tightest felt. It is interesting to note that the superfine merino has the most ‘crimp’ of all sheep breeds.

The softness of the felted garment comes from the quality (micron) of the wool and not from the amount it is felted. Many beginners make the mistake of stopping the felting process too soon because they like its ‘softness’, but unfortunately all they have really created is a pre-felt, a very under-felted piece of felt that will pill and look shabby quite quickly.

Hardening Stage

The felting process is divided into two stages – hardening and fulling.

Hardening Stage by Rolling or Tumble Dryer

The hardening stage is when the wool is laid down on top of thin plastic (or bubble wrap), wetted out with water, and rolled (or put in the tumble dryer click here to read more about this method) until the fibres begin to hold together just enough to be considered a pre-felt.  If pinched the fibres will easily pull away (Figure 1), but are beginning to hold together. The felt will have shrunk only slightly in this stage.

Figure 1

Fulling Stage

In the fulling stage I use both tossing and the washboard methods.

Fulling by Tossing

After removing the pre-felt from the plastic, begin tossing – lifting the wool in the air and dropping it on the table (Figure 2). At the start be gentle, try and think about getting air into your felt. As the felt begins to firm, continually open it up to be sure none of the edges are felting together. You will also need to begin to stretch your felt after each round of tossing. The stretching keeps the fibres from bulking up and allows the felt to form a more fully felted felt. Remember to keep the wool wet and soapy while tossing.  The water will add weight to your bundle so it drops more effectively with a thud. Continue tossing and stretching until the fibres are reasonably well felted and have shrunk 35%-45%. Shrinkage is an intragel part of fully felted felt!

Figure 2

Fulling with Washboard

I recommend further fulling your wool (after the initial tossing stage) by gliding the felt over a smooth corrugated surface. A beautiful well fulled felt can be achieved using the ridges on a double-cut glass wash board (Figure 3). Or my second favorite newly discovered item is a plastic painter’s tray which holds the water and has a corrugated surface (Figure 4). Some painter’s tray have very few ridges, make sure you purchase one that has LOTS!

Figure 3

Figure 4

Simply glide the work over the ridged surface with the aid of lots of soapy warm water. If your felt does not easily glide over the surface, you are not using enough soap or water. Work in a container to keep water and soap close at hand. If your felt is too dry and not well lubricated the fibres the surface will become fuzzy. The following items can also be used but are not quite as effective – hard blue swimming pool bubble wrap, ridges on the top of storage boxes or failing that the ridges on the drain board of your sink.

If you still need more fulling, especially on handbags, slippers and purses you can purchase a cutting board from IKEA and use the corrugated backside. This board is even more aggressive, so be gentle and use LOTS of soap and water.

Shrinkage will occur in the direction that you are gliding, turn work frequently – use this technique to specifically shape an area as needed. When you gently gliding the felt over these textured surfaces it compacts the fibres considerably more than tossing so expect more shrinkage. The results should be a smooth tight surface perfect for wearables where constant rubbing can result in the relaxing and pilling of fibres.

Final Considerations

  • Many people believe if your wool is fully felted it will lose its softness. Softness depends on the micron count of the wool (14-19 micron wool being the best for wearables next to the skin). If you are not used to fullling wool this fully, the result of your first attempt may end up too thick and a bit stiff. This is because there has been more shrinkage than you are normally used to.  The easiest remedy is to start with less wool in the initial laying out stage, this way when its fully felted felt it will not feel too thick or stiff.  Be sure to allow for 35%-45% shrinkage.

If your felt feels coarse or scratchy when it is fully felted, then usually one of the following things has happened.

  • Have you rubbed or tossed the felt without adequate lubrication (olive oil soap and cold-warm water)?
  • Have you shocked the wool by changing water temperature too dramatically? Don’t pour hot water over cold felt, warm up your felt slowly first with warm water.
  • Have you used boiling water in the felting process? On fine or superfine wools I rarely use boiling hot water unless I’m making a 3-D sculpture.
  • Have you microwaved the wool too long while attempting to heat it up (if you choose to use the microwave)? If the wool comes out so hot you can’t handle it, that is too hot!