Silk is a beautiful fabric to look at – butt not necessarily to sew. Working with silk takes a little extra care, but the results are well worth the extra effort.
There are many different kinds of silk and so the extra steps that you need to take can vary with the fabric. The white fabric on the left is dupioni silk. It’s made when two cocoons are bound together and has raised lines and bumps. This is a double thickness silk and I find that it can be sewn as for any fabric – the two sides don’t slide against each other when you are sewing a seam. The squared fabric above it is crepe de chine which has a slightly bumpy texture. This one is also less likely to slip when sewing seams. The floral silk on the right is probably what you think of as silk – very smooth and delicate. This one needs care!
Before you begin sewing silk
There are one or two constants: use small, sharp pins as silk can tend to show holes when the pins have been removed. Try to pin within the seam allowance so that any holes will not show up on the finished project. It is also best to use more pins than you would normally use as the pattern paper can slip against the fabric.
Needles also need selecting. I had always used sharps or quilting needles, very thin, when sewing silk. These should slip through the threads of the silk more easily. However last time I was buying silk the lady in the shop asked if I wanted ball point needles for it. I am so glad that she did! They are actually designed for knit fabrics, the idea being that the ball point will cause the needle to push the threads aside rather than break them. It works exactly the same with the silk threads – pushing them aside rather than breaking them and creating a potential hole. In the scrap shown in the photo I sewed a double line of stitching on the left with a sharp needle and a double line of stitching on the right with a ball point needle. I appreciate that you can’t really tell the difference from the photo, but believe me the ball point stitching is more smooth by a long way.
One further point before you start sewing: the presser foot. I have in fact used my normal presser foot for this project and the silk is feeding through evenly, but if you find that your fabric is not feeding well try a different presser foot. One with a smooth underside that will glide over the fabric. My zipper foot has a smooth surface which would be ideal.
How to sew a silk seam
So those are the main points to consider before you begin sewing. There are also things that you can do with the fabric to help smooth your sewing. If your silk is very fine and inclined to fray you may need to use a fine interfacing to stabilise it. This does make the fabric thicker which may not be what you want, so another choice would be to use stitch and tear. This will give your fabric stability while you are sewing seams, but can be torn off afterwards. I tend not to use this myself because I worry about stretching the silk when I tear the interfacing off.
Talking of stretching, it is always worth stay stitching any edges which are on a curve. Here I have run a line of stitching around the top of the skirt, taking care to sew within the seam allowance so that it won’t show when the seam is sewn. This just stabilies the edge so that it shouldn’t stretch.
The biggest problem is of course that the silk is so smooth that the two layers slip against each other when you are sewing a seam. With this particular fabric I found that it was enough just to take the seam slowly, sewing a small section and then adjusting the two layers to make sure that they were still in line with each other. As you can see, that gave me a perfectly flat seam.
Once you have sewn the seam (successfully!), you must finish the raw edge of the fabric because silk is much more likely to fray than cotton fabric. A line of zigzag along the edge should be enough to seal the raw edges of the silk seam that you have sewn.
Here’s the video: