How to Do a Fabric Burn Test to Identify Fibers
Learn how to do a fabric burn test that helps you identify what a fabric is made of. A burn test is performed by setting a small piece of fabric on fire, monitoring the flame as it burns, and inspecting the ashes after the flame is gone.
Knowing fabric content is important to quilters because we typically sew with 100 percent cotton. It's especially important to know fiber content if you exchange fabrics with others who expect to receive cotton fabrics.
No matter what type of project you are working on, from quilts to upholstery, a burn test that identifies fibers will help you determine proper care instructions.
Warning
Perform the burn test outside on a day that's not windy, or in a well-ventilated area inside, away from flammable items, children, and pets.
Think You're Buying 100-Percent Cotton?
Do you ever buy fabrics on eBay or at estate sales and flea markets? What about your non-quilting friends, do they ever offer to give you excess fabrics? Have you received unknown fabrics in a fabric exchange?
Unless you are sure that fabrics are cotton, there's no way of knowing their fiber content without performing a few tests.
Fabric Burn Test Supplies
Gather these items:
- The fabric(s) you want to test
- A flameproof container with walls—try a large ashtray and consider placing it in another container, such as a sink where water is handy.
- Long matches or another source of a small flame
- A pitcher of water to extinguish the flame if you aren't working in a sink
- Long tweezers or a hemostat
How to Do the Fabric Burn Test
- Cut small pieces of each fabric you want to test, such as 2-inch squares.
- Place a piece of the fabric in your fireproof container and ignite one corner.
- Pay attention to the odor of the smoke.
- Cotton smells like burning paper and has an afterglow at the end of the burn.
- An odor similar to burning hair or feathers indicates wool or silk fibers, but silk doesn't always burn as easily as wool.
- A darkish plume of smoke that smells like chemicals or burning plastic probably means the fabric is a cotton/polyester blend.
- Examine the ashes after they've cooled.
- Cotton ashes are soft and fine. They turn to dust when touched.
- Black, brittle remnants that crush between your fingers are probably the remnants of wool.
- Hard lumps are the remains of melted synthetic fibers.
- Take one more step. Unravel a clump of threads from another small swatch of the fabric. Hold the clump with tweezers (over your flameproof container) and slowly move a small flame towards the clump.
- Cotton fibers ignite as the flame draws near.
- Synthetic fibers curl away from the heat and tend to melt.
To see exactly how each type of fabric reacts, perform experimental burn tests on fabrics you know are made from cotton, cotton/polyester blends, wool, and other fibers.
Fabrics That Are Mistaken for Cotton
- Linen produces results that are similar to cotton but linen burns more slowly.
- Rayon keeps burning after the flame is removed, and although it has an odor similar to cotton or paper, it does not have an afterglow.
If You Don't Think the Fabric Is Cotton
There are no quilting rules that say you must sew with one type of fabric or another. Go ahead and use a fabric if you like it, but do try to determine what type of fabric it is so that you'll know how to care for the quilt when it's finished.
Most quilt block and fabric swaps require that you use all-cotton fabrics. Reserve fabrics made from other materials for your own use or for swaps that allow variations.
A lot of people believe that cotton is king. The great thing about cotton is that it is comfortable, soft and long-lasting. It is far cheaper than silk, yet looks great in any color. If you want to sit back and relax after a long day, nothing quite compares to the feel of soft, 100% cotton fabric.
That being said, 56% of all fabrics contain cotton in some form, and if you want to make sure that you are getting the maximum benefits, it helps to ensure that you are choosing 100% cotton as opposed to a cotton blend, or synthetic fibers.
If you want to find out if your clothing is 100% cotton, then it is wise for you to carry out the fabric burn test. The burn test is the best way for you to find out if your clothing is made with cotton fibers, and it's also very easy to carry out.
The Burn Test for Cotton Fabric
The fastest way for you to tell if something is pure cotton or not would be for you to use the flame of a candle, or a match.
Cotton will not melt, nor will it curl away from the flame. The one issue with the burn test is that a lot of all-natural fibers or even semi-natural threads will burn in the same way that cotton does, irrespective of whether or not it is 100% cotton. Some of these fabrics include flax, jute, ramie and hemp.
Wool and silk, on the other hand, do not burn in the same way as pure cotton. If you do carry out the fabric burn test, then you may be able to find out if you have a natural fabric or semi-natural fabric, but you will not find out if your clothing item is pure cotton. Wool and silk have a tendency to shrink from the flame, as synthetic fibers do, but they do not melt at all.
When you do use the burn test on 100% cotton clothing, you may find that you get a burning paper-like smell. Some people have likened the smell to burning leaves.
Silk and wool however have a very distinctive, heavy odor and this is very similar to burning hair. The main difference is that cotton comes from wool and plants, and silk comes from insects or animals. As you can imagine, the two materials have a very different compositions and therefore react very differently to fire.
Finding Cotton Fabrics via Touch
One way for you to find out if the fabric you have is 100% cotton or not would be for you to use the touch test.
This is ideal if you frequently wear cotton, and don't want to carry out the burn test on all of your clothing items. If you want to carry out this test, then you need to rub the material against your cheek. 100% cotton should always feel much softer when compared to other materials and it should also have way more texture when compared to polyester as well.
If you have polyester cotton fabric, then you may notice that this is slicker or smoother than cotton. All polyester clothing will have a much more artificial feel as well. Reading the label on your fabric is also a way for you to find the answers you're looking for. 100% cotton should always have a label stating this.
Of course, you shouldn't be harsh on yourself if you are fooled when you do the touch test. It is becoming increasingly difficult to find out if cotton is 100% cotton through touch alone. Manufacturers are now trying to create synthetic products that feel, and look just like cotton, so depending on the age of your fabric, this can be a tough test to do.
Cotton VS Polycotton- How to Tell the Difference
The best way for you to find out if your cotton is 100% cotton or polycotton would be for you to use the burn test, as detailed above. You simply need to take some scrap fabric or some threads from your cotton clothing and put a flame to them.
If you see that the fiber curls or melts, then this indicates that it is made out of polycotton. There should also be some goo, or residue left behind when the material has finished burning. Cotton on the other hand doesn't curl, it stays straight as it meets the flame.
It then proceeds to create the smell of burning paper or wood. When it has been consumed by the fire, it should leave some grey ash behind. you only need a few fibers to carry out this test, so be mindful of that.
If you notice that your clothing seems to wear out quite quickly, then this is also a sign that it is 100% cotton. Cotton doesn't last as long as polycotton, as it's not as durable. if you don't have the time to wait, then try and tear a piece of fabric.
Cotton tears far easier when compared to polycotton. The reason why fabric tends to be blended with cotton is because it has a lot of weaknesses.
That means the touch test may throw you off because it may feel exactly like 100% cotton. You would have to have a very sensitive touch to be able to distinguish cotton from polycotton.
Are my Socks Cotton?
If you have some socks and you want to find out if they are 100% cotton or not, then the burn test may not be the best solution. That being said, there are other options out there if you want to find out if the socks you have are pure cotton.
The first step would be for you to take note of how the socks feel against your skin. If the cotton is very pure, then it should feel different to other blends, and it should also feel a great deal softer when compared to other types of socks as well. When you have done this, you then need to wet the socks and let them dry.
One thing to note about cotton is that it takes way longer to dry when compared to blended socks. These tests might not be able to produce definitive results, depending on how you go about drying the socks.
If you have done this and not got the answer you were looking for, then you can try and wear the socks to see how hot your feet get.
Cotton is able to breathe way more when compared to any other fabric. This is especially the case when you look at polycotton fabric blends. How cool your feet stay should be a good indicator as to whether or not you have 100% cotton. Polycotton is also known for not absorbing moisture as well.
Characteristics of Different Fabric
If you look at different fabrics, you may see that a lot of them have numerous characteristics. This is a great way for you to find out if the fabric you have is true cotton, and if it isn't, what else it is blended with. Take a look below to see the top characteristics of the types of cotton out there.
Cotton- You should find that cotton feels somewhat stiff. You should be able to crush it with your fingers and you should also be able to put a crease in it as well.
Silk- Silk is incredibly smooth and it should also have a bright, or luster look. It is usually very easy to see if something is 100% silk from the appearance alone. Silk is very difficult to crease due to the silk fibers being so flexible.
Wool- Wool is very coarse and sometimes it is possible to feel fibers protruding from the fabric itself. Pure wool can sometimes feel rough, or scratchy to the touch. It is also usually quite thick when compared to other fabric, due to the natural fiber.
Polyester- Both polyester and rayon are smooth to the touch, and they also have a certain amount of luster to the look as well. Some would say that it looks similar to silk, but without the luxurious feel.
Twill- Twill is very coarse to the touch and it should also have a very diagonal feel to the material as well. Twill is often used in various types of clothing.
Velvet and Pile- Materials such as this tend to be smooth when touched, but they have a somewhat hairy structure. You may also notice that it comes with a lot of loops when you inspect the material closer.
So, this guide should help you to find out if the fabric you have now is a cotton blend or if it is 100% cotton.
If you aren't sure, then it is wise to consult the place where you bought your item. In the future, shopping through a reputable store that only sells 100% cotton fabric or clothing could be the best way to get the assurance you're looking for.