You will not find anybody who is working in different processing of apparel manufacturing but didn’t have any idea about GSM. Simply, GSM is the unit for the weighing of fabric. Actually not only fabric but GSM is also used specifying the weight of paper, lather or any sheet-like materials.
Meaning and Calculation of GSM
What GSM Stands for?
GSM is the abbreviation Grams per Square Meter. It says the weight of one square meter of fabric. That means if we make a piece of fabric whose area is just 1 square meter and weighted in a balance what the reading shows will be the GSM of that fabric.
Calculation of Fabric Gram Per Square Meter (GSM)
If we need to check/calculate the weight of any fabric, what we do? We cut a circular shaped piece of fabric by GSM cutter and put it on an electronic balance. Balance shows the reading 1.80 gram, we proclaim that the fabric has Gram Per Square Meter (GSM) 180 moving the decimal for two digits from the balance reading. Why we do this? Though GSM is the weight of one-meter fabric why we measure such circular piece fabric?
There is very silly but interesting math in it. Let’s have look.
Measurement of GSM
It is much difficult to measure fabric weight by making a piece of fabric of 1 square meter and it will be a wastage of fabric as we have to check the weight for several times of the same fabric. Then what can we do? If we make the specimen 1/100 of 1 sqm i.e., 100 square centimeters, now weigh the piece of fabric of 100 square centimeters and multiply the reading by 100, we will find the GSM of the fabric.
That means it is more convenient to measure the weight with a piece of 100 square centimeter, rather than 1square meter.
Now the problem is that our GSM cutter is circular shaped, not square. Let us think if the GSM cutter is square-shaped, will that be possible to cut the piece by screwing the cutter?
That’s why the GSM cutter is circular shaped. Now we need to find out a circle whose area is 100cm2. It is pretty easy, just back to the High School Geometry. We know, area of a circle is πr2.
Now if we summarized it then comes, the radius of our GSM cutter is 5.64cm and the area of the circular piece of fabric that we found by the GSM cutter is 100cm2. We will find GSM of that fabric by multiplying the weight reading of 100cm2 fabric by 100.
Senior Merchandiser at Centro Tex Ltd.