Sewing 108 - Fabric on Grain (Blocking Fabric)

This is an issue I didn’t quite understand early on in my sewing. I thought that once the fabric is neatly pressed and flat, you are good to go.

What does it mean for Fabric to be on grain?

This issue usually affects woven fabrics and not knitted fabric. As I mentioned earlier, your fabric has a length-wise grain and a cross-wise grain.

fabric grain lines

The fabric is on grain when the Lengthwise grain is at right angles to the crosswise grain, or when the Warp threads are perpendicular to the Weft threads. In short when the threads of the fabric are straight. This is also referred to as Blocking your fabric.

blocked fabric

If you fold the fabric selvedge to selvedge, the edges should be straight and at right angles to each other. Fabric will lie where it naturally will, so if you try to force it straight, you will have wrinkles.

grain line on trousers

The importance of being on grain is that it affects the drape or the fall of the finished garment, that is why your shirt is smooth and straight and your trouser legs are not twisted.

It also affects the alignment of stripes or patterns on the fabric that are made by weaving different coloured threads like the Flannel fabric above.

Please note that the pattern on Ankara and some other printed fabrics have nothing to do with grain lines. They are simply printed images on the fabric. As opposed to a fabric like Flannel or Check where the pattern is created by weaving different coloured threads together and therefore the straightness of the lines is directly related to the grain lines of the fabric

How to get the fabric on grain.

The first step is to create a straight edge on your fabric. This isn’t simply cutting the fabric in a straight line with scissors, rather it is following a straight line of the weave from selvedge to selvedge. There are 3 ways to do this:

a) Tearing the Fabric

b) Pulling the threads

c) Slashing with a scissors

Tearing the Fabric

This is the most common way of doing this and should work on most non-stretch woven fabrics with a tight weave. But do not use this on sheer or delicate fabrics.

(1) Make a clip into the selvedge edge 

(2) Pull the pieces apart 

(3) This should make a straight edge 

(4) Press the edge with an iron

Pulling the Threads

For fabrics that you may have difficulty tearing such as sheer or delicate fabrics, or fabrics with a loose weave, pulling the warp threads out is the next option.

(1) Along the width of the fabric, locate one or two threads that can be pulled out from selvedge to selvedge

(2) This will create a little gap or line for you to follow and you can cut along this line.

(3) Alternatively, You can pull out all the threads on the width until you find one that runs from selvedge to selvedge, this will leave a little fringe, but you can see that the edge is straight.

Slashing with Scissors

The final method is to slash the fabric with your scissors from selvedge to selvedge. The idea is that the scissors will simply follow the warps threads on their own. You need very sharp scissors for this and it may not work on all fabrics. Plus this method may require some practice.

(1) Insert the scissors on the selvedge at the point you want to cut

(2) Hold the fabric firmly between the blades of the scissors

(3) Make a small clip with the scissors and push through quickly and confidently while holding the fabric firmly, until you cut the whole length off.

Now that you have a straight edge, it is time to determine if your fabric is on grain or not.

(1) Fold the fabric in half, selvedge to selvedge. Simply shake out the fabric then let it fold naturally and smooth it out.

(2) If all edges are straight and aligned and the corners are at right angles, then your fabric is on grain, and you do not need to do anything else.

(3) If your edges are not aligned then your fabric is off-grain and you need to pull it back into shape.

One thing you should NOT do is try to pull those edges together to solve the problem. You will only end up misaligning the selvedges and that means the fabric is definitely not on grain as the threads are no longer lined up straight, plus you might also see wrinkles in the fabric

Blocking the Fabric

(1) Hold the corner of the fabric that is off in one hand

(2) Then hold the opposite corner in your other hand

(3) Pull/tug as it will be stretchy since you are now on the bias

(4) Fold again to check the alignment.

Switch corners and pull again if it is still not aligned. Do not pull too hard, just a little firm tug to straighten the fabric. If the fabric is only slightly of grain, ironing it with steam may help pull the fabric back into shape

Once your fabric is straight or blocked, it is now ready for sewing. I should caution that some fabrics like Ankara/wax print can be hard to block. In the case of Ankara which usually comes in 6 yards or 12 yards, what I have found is that the first 2 yards may be off, the remainder will be on grain, probably due to some stretching during processing. Generally, I don't advise you to try to block as much as 6 yards at a time. Work in smaller portions at a time. Also, if the fabric is extremely off, just try to get it to a happy medium even if you cannot get it perfectly straight. Sometimes you just have to be creative with these things.

Did you know that you can also watch this lesson?

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