Wool 

---

From sheep to useable wool, it takes a bit of work, starting off with 'scouring' (process of cleaning the wool):

A cut sheep's wool spreads out
like it could cover a minor SUV.


Around the edges, the skirt, you will
find a lot of undesirables...plainly 
speeking, sheep poop, so you start of by getting rid of these parts.

---

On the sheep, the dust and soil works its way down the fur.
It needs a bath, or rather a couple!
What you are left with is a mudbath.
The wool soaks in hot water and Woolite for an hour or so.
You will wash away the lanolin, the
waterproofing excretion, that is 
actually a kind of wax and not fat
Lanolin is used in cosmetics.

---

Repeat several times until the water
is clear.
To save our plumbing I started doing this in a wheelbarrow outside instead.
I had a hose going outside from the kitchen faucet.
Eventually runined the faucet with all my srcrewing on and off of the hose.



​Next is drying, and then you use your wool and dye it for the colors you need.

You need pigment and acid = vinegar

You keep the water just below cooking,
you add pigment and vinegar and
have it on the stove for half an hour or so.

---

Next you still need to clean the wool.

My wool has plenty of burrs and pieces
of the great outdoors.
You can use some fashion of 'wool comb', or whatever sturdy comb with
long steel teeth.
Some stuff will fall out as you brush.
A lot has to be handpicked.
This can be quite tedious work...

There are special wool combs to buy
($ 120), but it works with hair combs like the ones on the picture ($ 2-3). I usually use two taped together.


As regards the different burrs you encounter, I am very impressed by 
the foxtails.
(Our cat has had some very obnoxious,
painful and costly experiences with 
these).
The foxtail has 'botanical ratchets' that allows it to move by 'anisotropic friction'.
Interested?: www.ncbi.nlm.nih.gov/pmc/articles/PMC2677596/

​Physics of wool

The main idea of felting depends on the scaly structure of wool (as with humanhair and all hair that grows). The scales allow you to have the fibers grab hold of each other tighter and tighter the more they get felted, wether by agitation/friction or with a felting needle with notches that grabs the scales

Different wool is characterized by:
- thickness/ diameter in microns
- crimp = waviness, which gives loft and bounce
- staple = length of the fibers
- lustre/shine

All that depends on the breed of sheep, there are hundreds, but, for example:
- Churro = coarse and long wool, used by Navajo in rugs and blankets
- Romney = main breed in New Zealand
  medium thickness and average length
- Merino = the finest wool with a diameter of 15-25 microns, staple length 2-4      i
  inches. Naturally white, soft, non itchy