Step-by-Step Guide to Calculate GSM in Fabric
Have you ever done any thinking concerning how fabrics are measured with respect to their thickness and quality? GSM, which means Grams per Square Meter, is one of the significant terms in the textile industry, helping in this. This number is more than that of a number; it helps you know how heavy or light a fabric is, and it usually gives a fair idea of what that fabric feels like and how it sits and behaves when in use.
Whether you're at school learning the ropes of textiles, or those who are in the corporate garments industry or even a student who wants to advance their knowledge in fabrics, knowing how to calculate GSM can come in very handy. Here in this blog, we are going to take you through the step-by-step process of how to calculate GSM in the simplest way possible. You will end up being able to measure the weight of the fabric in a confident and accurate way with simple tools like the GMS round cutter tester, that are readily available at home or in a lab.
What is GSM in Fabric?
GSM is an abbreviation of Grams per Square Meter that measures the weight of fabric in terms of density per square meter. Put in simple terms it is an indication of how much grams a square meter piece of cloth would weigh. This is one of the basic and widespread measurements in the textile line, which is applicable in the fabric specification, quality assessment, and selection of the product.
The higher the GSM, the thicker and heavier the material whereas, the low GSM material is lighter and thinner. GSM is not the type of fiber (such as cotton, polyester, etc.), but the weight and density of the whole fabric. It may happen that two fabrics are similar by appearance and touch, but their GSM will help you to determine which one is better to choose according to a specific purpose.
What is the importance of GSM?
The knowledge of GSM is essential since it has direct impacts on the behavior of fabric in the real world. Some of the reasons why GSM is important are as follows:
- Fabric selection: GSM will be useful in fabric selection because when selecting a specific product, examples are T-shirts, jeans, curtains, and upholstery, the GSM will assist in making a good choice in the type of fabric to use. This is illustrated whereby summer wear should have a low GSM, whereas winter coats should have a high GSM.
- Quality Control: GSM is used in the maintenance of consistent quality in production. And when you are making hundreds or thousands of garments, the GSM will tell you that all your pieces are to the same specification.
- Pricing of fabric: Another way in which GSM has an impact is on the cost estimation. The cost of heavy tissues is normally high because they need more raw material. GSM is also used when buyers and sellers are negotiating the rates.
- Durability and Comfort: GSM enables one to know how tough or delicate a material can be. The GSM fabrics of a higher make can be more durable and provide more protection, and lower ones may provide a softer and more breathable feel.
The Equipment that You Require to Compute GSM
Calculation of GSM requires machines GSM round cutter machine. Either the job can be done with a few plain articles:
- A sample clean piece of fabric
- A pointy pair of scissors or a rotary knife
- A ruler or an instrument of measurement (ideally in centimetres)
- A digital weighing scale (one which is measured in grams)
- Fast math with the calculator or mobile phone
These things can be typically found at home, in the laboratory, workshop or classroom. Here are the breakdown how you can test GSM of fabrics without using GSM round cutter machine..
Step 1: Cut any piece of fabric.
You may want to start by setting a small piece of fabric in the square 10 cm by 10 cm. This is the most standardized sample size since it is easy to measure and yield fast results. Ensure that the cut is even and straight all around. Any additional lines or incorrect edges might interfere with your calculation.
Do not pull and bend the material when cutting. This is ideally done with a rotary cutter and cutting mat but ordinary scissors and ruler will do just nicely.
So you can have a small sample (less than 10 cm x 10 cm) or large sample (greater than 10 cm x10 cm), and that is alright. You may still compute GSM, but modification of the formula to suit your sample size will have to be done as we shall see below.
Step 2: Weighing the Fabric sample
At this juncture, you have your fabric sample and therefore carefully place it on a digital weighing scale. You should ensure that the scale is clean, calibrated (zeroed out) and that it displays grams (g). The variation in weight as little as it may be can influence your GSM value.
Record the weight of a fabrics sample. Take an example, the sample is 10 cm by 10 cm which gives a weight of 4.8 grams.
In the case of thick fabrics or layer (thin fabrics rolled together as quilts or layering coated fabrics) it is important that the sample be one layer and properly able to have the size trimmed correctly.
Step 3: Compute GSM
Here, the math comes in, but don’t forget this is very simple.
In a sample size of 10 cm x 10 cm, we have an area of 100 square centimetres and 10000 square centimetres are contained in one square meter. Your sample is 1/100 th of a square meter, so all you have to do is multiply the weight of your sample by 100 to get the GSM.
GSM = 100(Sample Weight in grams)
In our case: GSM = 4.8100 = 480 GSM
This implies that the weight of fabric is 480 grammes / square meter. This is looked upon as a heavyweight and it is normally applied in jackets, workwear or in upholstery.
Suppose that Your Sample Size is different?
In case your fabric sample is smaller in size, i.e. 10 cm x 10 cm, it is not the case; you can determine GSM by following the formula shown as an example:
GSM = (Sample weight in grams / Sample area in cm 2 ) x 10,000
Suppose 20 cm x 20 cm is your sample, or 400 cm squared, and it weighs 10 grams.
GSM = 10/400 GSM = 250/10,000 GSM
The technique can be applied at any sample size, provided that you weigh the area and weight.
Backchecking or Double-checking
To make your GSM value closer, it is better to test not only one sample but samples in the different zones of the fabric. Take three or four slits, measuring the GSM of each of them and averaging the result. This will assist you in making allowance for any variations in thickness or weave in the roll.
The procedure proves exceptionally functional when it comes to bulk production, or with materials as fabrics, which may possess a finishing or treatment on the surface.
The Understanding of Different GSM Values
GSM value is the standard value of different materials that are used in different fabrics. Some of the common ones are:
- 80 to 120 GSM: Lighter garments such as voile, chiffon or linings
- 130 to 170 GSM: Medium weight, such as shirts, summer dresses or T-shirts
- 180 to 250 GSM: Heavier bathrobe, T-shirt, belt and linen
- 250 to 450+ GSM: Towels, Koozies, denim, jackets, upholstery, or carpets
Nevertheless, GSM is not the identifying factor of fabric quality solely. It must be noted together with other aspects such as thread count, type of fibers, weave and finishing.
Typical Errors to be Avoided
GSM values might sometimes assume an inaccurate value simply because of errors. These are some of the things to watch out for:
- Failure to cut a perfect square sample
- Using weight that may be extra threads, dirt or creases in the fabric
- Putting a non-calibrated or inaccurate measuring scale
- Making a mistake in the calculation because of the incorrect measurement of the area
- Applying multi-layered / coated samples without taking layers into consideration
It can take you a few additional minutes at the end to retest your sample and calculation, and avoid deceiving findings.
Conclusion
Probably the most significant and simplest instrument that we have to know the character of a fabric is GSM. A professional in the textile industry and a interested learner will understand how to calculate GSM aids in getting deeper insight on behavior, quality and use of the materials.
All you need is a tiny sample of the material, a digital scale, and a little bit of arithmetic to determine the GSM, and having this information at your disposal, you make wiser decisions, whether you mean to test a material consistency in a factory or buy an ideal fabric to do a project.
It is time to give it a go now that you have perfected the steps. The thing is to cut a piece, weigh it and do the calculations--and Test Your Product with assurance.
