# Chapter 1. Factors impacting felt quality

The wet felting process involves moving fibers with the help of water
and agitation to create an unvowen fabric. This results in fibers
moving around to form a random organization and the scales (barbs) in
the wool to get caught up with each other to lock them in place. The
resulting felt quality, look and feel of it, its density, flexibility,
drape and overall structure can vary greatly based on a large number
of variables.  Crafts people and artists have depended on these
variables for centuries to produce felt for a large number of
different uses. The breed of sheep or other wool animals are one of
the many factors that impact felt quality and structure.

In this chapter, I will summarize these variables and group them into
four basic groups:

1. Fiber processing
2. Animal husbandry
3. Breed characteristics
4. Wet-felting process

First, let's consider each group in isolation and its impact on the
fiber and the resulting felt.


## Fiber Processing

The process to prepare the fiber may have a big impact in the felting
ability of wool. Examples are:

- The cleaning process: the temperature of water used to scour wool,
  chemicals used, level of fiber manipulation, amount of lanolin left

- The carding process to produce roving or batting, breakage of fibers
  which produces more fiber ends, the orientation of wool (single
  direction in roving vs. random in batting). 

- The use of chemicals: chemicals used in post process to coat the
  fibers and dye them


## Animal husbandry

The large number of variables may exist within a single breed of wool
producing animal used in wet felting. These would impact the quality
of the wool from farm to farm, from season to season. Examples are:

- The domestication process: selection of animals for wool quality,
  genetic diversity in the farm

- Labelling conventions for sheep/wool, availability of registry for
  the breeds

- Variability of wool quality within the animal, some animals
  naturally have many different quality of wool on them (eg. llama)

- Age, well-being, nutrition of the animal, winter vs. summer coats

## Variability between breeds

Variability between breeds is sometimes attributed to many of the
other factors described in this chapter. It is important to
distinguish between the breed based criteria by using many different
samples of the same breed from different farms and sources.

Additionally, beware of the granularity for describing the breed. The
breed name is not always sufficient.

The main variability between breeds is understood along a number of
basic dimensions:

- Fiber thickness (fine, medium, coarse)
- Fiber length (short vs. long)
- Fiber composition (dual coated, hair and kemp mixed, crimp or not crimp)

In addition, there are a number of less documented properties such as
the structure of the scales which likely play a role as well. 


## Process used in wet-felting

The process of wet-felting goes back to ancient times and is
surprisingly unchanged since then. Through experimentation, some
ancient and some recent, many variables have been discovered. We
outline a few here. Each will constitute their own section later.

- Layout: thickness of layout, directionality of the layout

- Process: soap used, temperature, agitation process, the amount and
  direction of manipulation

- Mixing with non-felting (or hard-felting) fibers, including
cellulose fibers (rayon, bamboo, tencel), protein based fibers (silk),
metal fibers. Additionally, using fabric and paper of many types in
felting.

Additionally mixing of felting fibers in different ways is another
  topic worth discussing. I will go over this in particular when
  mixing different breeds of fibers either by carding them together,
  layering them horizontally or by using different fibers in different
  parts of the layout. Of course, fiber genetics may also mix in
  sheep, which in itself is an interesting topic of discussion.