Sunday, 8 December 2013

Bias Binding

Hi there!

Sally hung her bunting up for Christmas.

So I'd best get this post up too!

I'm going to have a look at making bias binding today.

I've talked about binding before on stretch garments. Bias binding is quite a bit different in that it is for woven fabric. It's a very useful thing to know about. It can be used to make straps, finish edges, finish seams. Bias binding can make the inside of your garments as beautiful as the outside! Oh and it can be used to make bunting which is my current focus. :)

The Bias.

When fabric is woven, it has threads going in two different directions - up and down, and left to right. So if you imagine the vertical threads on a loom here:
On the edges you have the selvedge, (marked in green) which is a firmer strip where the horizontal threads double back across the fabric. You will often see pin marks and brand  / designer names are printed along the selvedge.

The vertical threads are called the warp. They're the stronger threads. Generally when you make a garment, you will be aiming to have the warp threads (the grain line) running straight up and down the figure.

The horizontal threads are called the weft.
As a way to remember which is which, the weft goes from right to left.

If you pull across the warp, or if you pull across the weft, neither direction are stretchy.

However, if the fabric is pulled at a 45° angle, those threads can move and flex a little. That is the bias. Check it out - grab a tea towel, pull across and pull on diagonal corners and see the difference.

Bias cut clothing is cut on an angle. So instead of putting your skirt pattern on the fabric parallel to the selvedge (the firm edge) you put your pattern piece in such a way that the centre line of the pattern piece is on a 45° angle to the edge.

If something is cut this way, it has a little more stretch and movement than it would have if it were cut with a straight grain. This is why bias cut skirts are known for being flattering.

Bias binding is cut on a 45° so that it can be a little flexible, and curve beautifully and smoothly around edges.

Making Bias Binding

To make it, start by drawing a line 45° to the selvedge edge of the fabric. It doesn't matter which side.

You can do that by measuring with a set square or by folding (which is what I did). If you do fold, press carefully and take care not to distort the edge. You can get a feel for the movement of the fabric as soon as you fold it! Cut that piece off on the line.

You then bring this piece around the other side, and stitch it along the selvedge to make a parallelogram.  Start with a reasonably wide seam, then trim the seam so that the selvedge is removed as it can behave differently. Press it flat, and you will effectively have this.

Once you've done that, mark out the strips. I made mine 4cm wide and my binding ended up about 16mm wide. I was aiming for 2cm, but I forgot that you need to cut 4x the width plus a little bit, because the stretchiness means it distorts and becomes a bit skinnier. I chose 2cm because I will fold it over the edge, and I want 1cm showing on each side.

I marked mine out with chalk. If I had a rotary cutter and mat it would have been a bit faster! A rotary cutter is like a razor sharp pizza wheel. You can use a ruler like this, or a quilting rule and just slice off the strips. Cool, but not strictly necessary. I don't have a lot of call for one, so the occasional labour involved in cutting something like this with scissors isn't an insufferable tragedy.

I'm making 8m of bunting, so I want 10m of binding. I cut strips accordingly. And then a bit more because I got into a groove.

Because I want a continuous strip (for presumably obvious reasons) I need to connect those strips.
Being mindful of the right side of the fabric, I join them like so.

 The edges must meet at the seam! I then trim it back
 And press. Preferably before taking the photo but it's a bit late now.
Because the seam is diagonal to the strip, it wont add too much bulk in any one place. If I joined the strips straight across, there would be twice as much fabric in one spot. This way the extra bulk is distributed and keeps the join smooth.
 I repeat this a few times, and I have a pile ready to press!

To press, I first put some music on, because I'm going to be here for a while.

I fold the strip in half along the length and press lightly, as this will form a guideline for the middle.
Then I fold both sides into the middle, and use needles to hold down, exactly as I did for the stretch binding.

I press, and ease it through bit by bit, checking that the edges stay in the centre, lining up with my middle fold.
The result looks like this:

This is how purchased binding looks, although the edges often don't meet in the middle. Sometimes you will see a gap between the edges - folds over 6mm  and then a space. It will depend on the width of the binding and what it is made from.
Commercial stuff looks like this.
Then I pressed it in half again. In this respect I am taking a slightly different approach to the purchased binding. When you buy binding it will come with two edges folded in, and no middle fold. But I am going to fold my binding in half as I sew, so by pressing now I encourage it to do that easily.
Iron that too!

Once I had my fold over binding, I was ready to construct the bunting. I laid out the flags, so I could keep track of the pattern I wanted to assemble them in.

I sewed the first meter of binding on its own, with the folded edge on the right, and the open edge facing away from the machine. I want my stitches a few millimeters from the fold, so I used the edge of the foot as a guide, and moved the needle position slightly.

After the first meter, I stopped and put in my flag. I want to sandwich the raw edge in the folds of the binding.

 As I get to the end of one flag, I pick up the next. 

Take it slowly and make sure it isn't slipping! With all the pressing done it is fairly co-operative. At the end, I made another metre just of the binding. And it was done!

Be sure to wrap any remaining binding around a piece of card to keep it flat - you want to look after the creases you went to the trouble of putting in.


  1. Finished bunting looks great.

    The bias binding pin method was a revelation when I discovered it earlier this year. No more burnt finger tips!

    Weft - Left, that is how I aways remembered it!

    1. It was good to try it on a woven rather than a stretch this time around. I'm thinking of making a skirt with bound seams (when I finish the other zillion projects I've started). Have you seen Amanda's sewing adventures?
      Her earlier stuff (before she got the overlocker) was amazing because she always bound and finished the inside as beautifully as the outside. I've spent a lot of time focusing on fit. But now that I've got a better handle on the shape, I'd like to get a bit of that kind of detail in there too!