Saturday, April 16, 2011

Burn Testing an Unknown Fibre

Last fall when we purchase Ngaire’s Louet Spring I bought some great cotton and silk yarns and at the same time I got these very pretty shiny cones, now why is that not a surprise? I bought the whole stock of this yarn, because I'm a magpie and love shiny things! But what the heck is it? After a fruitless internet search, I decided that I’d better do a burn test to find out exactly what the fibre content is.I decided to run the test on known fibres to act as a base line and to ensure that I was doing the burn tests correctly. I chose to burn silk, linen, cotton and this unknown fibre. Armed with my Mary Blacks ‘Key to Weaving’ a box of matches and a plate I was ready for my burn tests. Silk was the first under the flame and it should burn with a sparkling orange yellow mantle. Silk should burn steadily with a slight sizzle then self extinguish. Linen was next in line and it should burn orange yellow and sparkle and crackle.Linen then smolders until self extinguishing. Cotton burns with yellow orange flame and leaves a delicate black or grey skeleton and emits wisps of bluish smoke. Cotton doesn’t self extinguish.Now it’s time for the Chyrsella, my mystery fibre. It exploded into flame and burned with a bright yellow flame and gave off black smoke. It burned so fast that I got of small speck of this napalm on my fingernail and OMG I hit the water pretty fast! The yarn ignites and burns very readily and is not self extinguishing and left a tarlike residue. I believe is Acrylic yarn. This is the result of my burn tests. It was a fun fibre exercise and I learned how to pay attention to details while you hold onto fire and ~ to always keep a bowl of water at hand! I had a bit of cotton warp left on my loom and I quickly wove up a sample with the red Chyrsella to see how it behaved. It stayed on the bobbin very nicely, unlike some rayon which can have a tendency to sproing off the bobbin. When I popped the sample in the water I was gob smacked by the smell! Weirdly, acridly, manmade is the only description that fits. The yarn was colour fast and when dried had no odour and a beautiful soft feel. The odour of the yarn when wet is something that I don’t think can be overcome, so this yarn will never be used in garments or table linens. I now have some very beautiful yarn that will be dedicated to weaving cards or wall hangings or whatever I can come up with…..but ohhhhh it’s so pretty!

5 comments:

Joanna said...

Hmmm,with those burn characteristics, it would be safer as cards/wall hanging anyhow~ I'm just learning to pay attention to such things.

Susan said...

Great post! I think that all weavers should be familiar with doing burn tests as most will run across a mystery yarn at some point!

Your mystery yarn sounds downright dangerous... but then some acrylics need to be handled carefully. What is off gassing to produce that smell? I wonder what a hot iron would do to cloth made from this?

Susan

dorothylochmaben said...

What a useful post ! I have two cones of unknown yarn but now I can test them and see what's what. I suspect they are acrylic though !! Thank you for sharing !

Lynnette said...

Hi Susan,

I wondered the same thing about ironing and so I first pressed it between a linen press cloth. It didn't smell or melt. Then I got brave and used the iron directly and again, no smell no melting....seems it just doesn't like being wet! Weird eh?

Peg said...

Your sample is, indeed, beautiful. What pattern did you use?