Monday, November 3, 2014

Tutorial: Identifying Mystery Yarn & Fiber with a Burn Test

Not too long ago, I was given some very pretty spinning fiber which didn't have labels:


Despite having no idea what I was working with, I spun up the pink and purple braids pictured above to create this lovely skein:


After spinning with it, I had an idea of what I thought the fiber content might be, but I have been meaning to perform a few tests to confirm or deny my suspicions. It wasn't until this past weekend that I finally got a chance to perform a Burn Test, which is a very common way to assess the fiber content of a mystery yarn or fiber. I filmed my process and added it to my YouTube channel just in case anyone was interested to see the Burn Test in action; below are the steps I followed and some more detailed information to help you identify your fibers, should you decide to perform a burn test of your own.


First: BE VERY CAREFUL! I'm sure you don't need me to tell you that setting things on fire is dangerous, but please be sure to keep safety in mind every step of the way. Placing a candle in a pan of water is a really good idea - if you don't believe me, watch the video above, because that pan of water REALLY came in handy!

Make sure flammable items are far away from your work area. Set up your materials on a stable surface in a well-ventilated room; you'll want to keep pets and children away from your work area, too. Also keep in mind that long hair or curtains by an open window should be secured. Hopefully, that covers all of the safety precautions you need to take so that we can continue to the fun part: setting things on fire!

First, you'll want to have some yarn or fibers samples for which you know the fiber contents: cotton, wool, silk, acrylic, or linen are all examples of samples you way wish to amass. In my video above, I chose to use cotton, wool and acrylic yarns for my basis of comparison.

The results of my burn test.
For each yarn or fiber, you will want to perform the following steps: 

1. Move yarn or fiber near the flame.
2. Move yarn or fiber into the flame.
3. Remove yarn or fiber away from flame.

With each step, be sure to make note of how the fibers behave: do they move towards or away from the flame? When placed in the flame, do they ignite easily? When removed from the flame, does the fiber burn steadily, melt, or immediately self-extinguish? What does it smell like as it burns?

All of these questions will help you make an educated guess as to what type of fiber you have.

Cellulose fibers (cotton, flax, hemp and ramie) for the most part smell like burning paper (flax is the exception, which smells like a grass fire when burned). They ignite easily and continue to burn when removed from the flame.

Protein fibers (wool, silk and alpaca) smell like burning hair...which makes an awful lot of sense, wouldn't you say?! As noted in my video above, wool is well-known for its self-extinguishing properties. While wool and silk ignite easily, Alpaca fiber is harder to ignite. Most protein fibers produce a bluish-grey smoke.

Manufactured fibers (nylon, rayon and acrylic) ignite quite easily; both acrylic and nylon are known for melting when exposed to flame. Nylon yarn will move away from the flame and will self-extinguish when moved away, though it will continue to burn if left in the flame, even after it has melted. Rayon does not move away from the flame, nor is it self-extinguishing. Acrylic yarn burns very hot and will spatter and melt; it is also difficult to extinguish, which is why acrylic yarns are not recommended for making baby items in particular.

For more information about how to interpret your burn test results, check out The Intentional Spinner by Judith MacKenzie McCuin, which was my reference when embarking on my own burn test adventure. Other helpful resources include this page on the Dharma Trading Company website and this comprehensive chart on the Fiber Images website.



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