(Almost) All About Fibers!!

When I started knitting, I knew almost nothing about the various types of fibers used to make yarn and fabric.  Since I grew up in Florida, where we rarely wore wool, I thought of wool as something very hot and scratchy.  My earliest knitting projects were all from cheap acrylic yarn because it was the most inexpensive yarn available and because I didn’t know much about different fiber types.  Once I discovered nice, soft wool, shiny cotton, and alpaca, I was on my way to becoming a full-blown “fiber snob”!  I wanted to work with only natural fibers.  Acrylic and nylon were dead to me!

Thankfully, I learned my lesson before I became too terribly obnoxious about natural fibers.  I still love wool, silk, alpaca, and all the other great natural fibers, but I’ve learned that there is a time and a place for everything (see the book of Ecclesiastes).  Here are some of the things that I’ve learned about various fiber types and when and where they are most useful.

Wool

Wool is the quintessential natural fiber.  It has been used for millennia to keep us “hairless apes” warm and dry.  Sheep are shorn and the wool is cleaned and spun to give wool yarn.  Some wool is scratchy and is best kept for use in rugs and other non-garments uses.  Merino wool is from sheep originally from Spain and is the softest wool.  (Note: I’m using “wool” to mean the fiber from sheep.  Cashmere, angora, etc. are also considered wool, but I’ll deal with them separately.)

Advantages:

1. Wool is warm.  The fibers are crimped and have scales, both of which help wool to trap air and act as an insulator.
2. Wool keeps you dry.  The fibers are hollow and can absorb about a third of it’s own weight in water.  Wool socks are great because they wick moisture away from the skin.
3. Wool is an elastic fiber.  When working with wool, blocking is essential and can cover “a multitude of sins”!
4. Wool can be felted (or fulled, which is probably a more correct word) with warm water and agitation, making a thick and water-resistant fabric.
5. While wool generally can’t be washed, it can be made into “superwash” wool in which the yarn is treated physically or chemically to get rid of the scales on the fibers that cause felting.  This yarn can be washed!  Many yarn companies now also carry a “superwash” wool in addition to regular wool yarn. 

Disadvantages

1. Wool prices have been going up in the last couple of years, at least partly due to natural disasters in Australia and New Zealand.
2. Wool allergy is rare, but possible.  Wool is made of protein, so the body can have an exaggerated (i.e. allergic) reaction to it.  However, it is rare.  If you are concerned that you might have a wool allergy, you should have a talk with your family doctor.
3. Bugs like wool.  Store your wool in closed containers – and it wouldn’t be a bad idea to throw a few pieces of cedar in there, too. 
4. Wool will felt when exposed to warm water and agitation.  Don’t ask how I know this!

Cotton

If wool is known as the fiber for cold climates, cotton is known as the fiber for warm climates.  Cotton is the fiber from the boll of the cotton plant and is pretty much just cellulose.  The bolls are harvested, then processed to separate the fiber from the seeds and make the yarn.

Advantages:

1. Cotton is very absorbent, making it great for dishcloths.
2. Cotton can be quite affordable.
3. Cotton is often paired with acrylic to make a yarn that allows for more elasticity.  Very helpful for garments.

Disadvantages

1. Cotton is very inelastic.  Blocking will NOT help fix problems in the knitting or other process of garment construction.
2. Cotton also can feel rather “dry” to work with.

Acrylic

Acrylic is NOT a bad word!  Please don’t be a “fiber snob” – give acrylic a chance!

Acrylic fiber is a synthetic polymer which is made by a really interesting chemical process that I won’t describe here because I realize that I am more geeky than the average knitter. 

Advantages:

1. Acrylic yarn is often cheaper than wool.  That being said, there are some high-end acrylics out there that you would be hard pressed to differentiate from wool.
2. Acrylic yarn is resistant to moths and sunlight.
3. Acrylic fiber can be added to natural fibers to make very satisfactory yarns at a more affordable price.
4. Items made with acrylic yarns are washable!  This is the big selling point of acrylic yarn.

Disadvantages

1. Cheap acrylic yarns have given the entire fiber type a bad name.  But, it is true that there are some kinds of acrylic yarn that feel almost like plastic.  Ick.
2. Acrylic yarn tends to “pill” and be very “static-y”.

Rayon and other semi-synthetic fibers

These are fibers that are made by polymerizing naturally occurring compounds like cellulose.  Rayon is made from cellulose from trees.  Bamboo fiber yarn is made using the same process with bamboo.  There are even fibers now made with seaweed!

Advantages

1. Semi-synthetics can imitate the properties of cotton, wool, or silk.
2. They are smooth fibers and do not insulate body heat, making them ideal for warm climates.

Disadvantages

1. There have been some environmental concerns with these fibers.  They are touted as being “natural” because they start with a natural product, but the processing is almost as extensive as with synthetic fibers.
2. These fibers have been going up in price because of an increase in demand after the price of cotton went up.

Nylon

Nylon is similar to acrylic because they are both long polymer chains, but they are different because of what the base chemical for the polymer is.  (As an interesting aside, I made nylon in my organic chemistry lab class in college.  However, the fibers were very thick and not at all useful.)  Nylon is often added to sock-weight wool to add strength to the yarn.  It is often used with acrylic fibers to make “baby yarn” – soft yarn that is washable.

Silk

Can I just say right now how much I LOVE silk!  Silk is from the cocoons of mulberry silkworms.  It’s a labor intensive process, which is part of the reason that silk is so expensive.

Advantages

1. Silk is very shiny (which has to do with the shape of the fiber and how it refracts light) and beautiful.
2. Silk is a very strong fiber as long as it doesn’t get wet.

Disadvantages

1. Because of the labor required to raise silkworms and harvest the fibers, silk is a rather pricey fiber.
2. Silk is not very elastic.
3. Some people have ethical concerns about killing silkworms just for the silk.  Honestly, I’m not too fussed about it.

Cashmere

This fiber is from the cashmere goat.  It is known for it’s softness and warmth.

Mohair

Mohair is from the Angora goat.  It is not a very soft fiber, but is known for it’s warmth.  It is often used with wool to make a warm yarn with a “halo” effect.

Angora

Angora fiber does not come from the Angora goat, but from Angora rabbit.  Confusing?  Yes.  Both angora and mohair yarn have a “halo” (or fuzziness).  However, angora is a very soft fiber.  It is often blended with wool to increase elasticity.

I realize that I’ve just scratched the surface when it comes to fibers, but I hope I’ve educated you a bit.  The more you know about fibers, the easier time you’ll have with your knitting or crochet project.