Monday, July 28, 2008

I've Been Duped!

Still trying to figure out the Mystery Fabric, I decided to do a burn test. Now, I"ve never been any good at the burn test, but I figured, Why not give it a shot? I had my tweezers, fabric swatch and a match. You can see the result here.

My "high quality wool"(sales lady's words) appears to be 100% polyester!! First I looked in my More Fabric Savvy book by Sandra Betzina. It has burn test information, but a couple of the definitions were the same for different fabric types. Then I looked in Claire Shaeffer's Fabric Sewing Guide, and it has much more specific information. Here is the definition for wool: Burns slowly, self extinguishing. Smells like hair. Residue is a small, brittle black bead.

Hmmm, my fabric burned and pulled away from a big yellow flame, melted and glued itself to the paper towel underneath. Not wool.

Here is the definition for polyester: Shrinks from flame, melts and fuses, black smoke, self-extinguishing. Sweet smell. Hard black or brown bead.
Yep, it's polyester. I didn't smell anything (everyone in the valley has sinus problems) and the goey stuff turned to hard plastic when cool. Yes, I'd say we have polyester here.

I was of course, hoping for wool. Well, it feels like wool, drapes beautifully and has the added benefit of wash and dry. I'll have to make it into something and see how it wears. The only problem I have with polyester is that it makes me perspire more. It doesn't seem to bother me as much in pants or skirts, so I'll have to figure out what I'm going to do with this now.

My curiosity was up, so I tried a few other fabrics with known content to see how they responded. I also had another cut of "silky wool" which is what the blue fabric was supposed to be. This one had a different effect. It burned quickly, kind of sizzled and flickered in the flame, left a gray ash, did not burn itself out. The residue was a black bead, but it was crushable. I think this one is a blend. Maybe wool and silk or another synethetic fiber. It did not burn as quickly as the cotton sample I had. Blends are hard to tell. Here are some of the indicators

flame sputters - silk, acrylic
crushable black bead - silk
brittle black bead - wool,
hard, brittle charcoal - acetate
but, silk burns slowly and is self extinguishing. This did not fit those categories

not self extinguishing - acetate, triacetate, acrylic,

This may be a good part acrylic because here's the definition: burns rapidly, hot flame, sputters and smokes, not self-extinguishing. Smells like hot vinegar. Crisp, black mass. Some of the definitions are confusing to me. Like, what is the difference between brittle black bead, brittle charcoal, crushable black bead, and brittle black mass?

I think the trick to the burn test is doing a lot of practice pieces on fabrics that you are sure of the content. Also, maybe I should have used a bigger piece of fabric. Mine were a little under one square inch.


cidell said...

Darn with the duping! I didn't do a burn test until last year when Trena made me. I just was nervous about doing it. But, it's a great way to figure out fabrics.

Christina said...

Darn, I guess it was too good to be true for that price, but it still sucks. It's false advertising.

Alexandra said...

False advertising, for sure. What's the deal with the selvage saying it's linen?

Marji said...

My first reaction, when I read your burn results was, this is probably acrylic.
Acrylic is a lot more likely than poly to have the hand and look of wool. Acrylic flames.
That said, before your next burn test, separate some yarns - unravel the fabric, and burn the yarns to get a better "read" on your fiber content.
And, know that finishes and dyes will affect your burn test.
I'm on my way out the door now, but when I get back, I'll look up the solution you can soak this fabric in to get a more definitive read on what it might be.
I'm still leaning towards 100% acrylic.

Gorgeous Things said...

The sizzling flame is an indicator for acetate. It sounds like a blend. There was a great online source for burn test results at the University of Nebraska, but I heard recently that it had been taken down. Sandra's book is also really good, but this one was exhaustive.

Emily said...

What a bummer! I've had that happen a few times as well -- I thought something was wool, but I discovered it was a blend. Anyway, another test that I like is the bleach test -- if you put a bit of fabric in a cup of bleach, wool should dissolve in the bleach; synthetics do not. Of course, that doesn't help determine which synthetic it is, but it's still kind of fun to watch how fabrics react to the bleach, I think. :)

Nancy K said...

There was a great fabric store in NYC NY Times building displaced it, any way, I remember them doing a burn test in the store if they weren't sure of some designer end that wasn't labeled. Ask for a burn test if you are not sure.

Nancy Winningham said...

Well, since the sales lady at Hancocks was convinced it was wool, but only after I convinced her that it wasn't linen. I'll bet she doesn't know how to do a burn test. Maybe I'll have to bring my "science kit" along with me next time LOL!