Whether you sew bags or clothes, from time to time, you'll need to use an interfacing on your projects and it can often be difficult to choose which one works best with which project.
Many sewing patterns usually will make a suggestion, but not list an essential interfacing product, because availability varies so widely that what is available in one area or country, can not be found in another area, making a person in that area reluctant to buy a pattern when the stipulated interfacing can't be used.
So let's take a look at a few examples today and you can see in the video how they change the structure of the fabric in each case.
Comparison of different types of interfacing
Fusible versus Sew in
Fusible interfacing has a fabric ‘glue' on one side. You can usually see this quite easily as a shiny glow on the interfacing or feel it as rough tiny dots. Mostly the fusible glue is on the one side, but it can sometimes be on both. Always take care to read the instructions that come with the interfacing as methods can vary, and try not to get the glue on your iron – it makes a nasty mess and can transfer to other projects or your ironing board next time.
Sew-in interfacing can come in many varieties and can have much the same features as the fusible – but without the glue. You'll normally secure the interfacing to the fabric before sewing the project by basting it within the seam allowances, although sometimes you may just layer up the fabric and interfacing and sew together. Check what is called for in the pattern instructions. Ideal when you have a fabric that cannot be ironed or have texture.
Pros and cons – Sew-in interfacing can be a little more tricky to work with because you need to keep an eye on all those layers, but it can give a nicer result on light weight fabrics because it will still allow them to show their original fabric properties. You may also find the project is less likely to crease with a sew in (although that depends on your fabric). Using a sew-in product also will allow you to trim excess bulk from your seam allowances if the project would benefit from that.
Using a fusible interfacing can be easier to keep track of and you simply fuse and then have the one layer to deal with in your sewing = less shifting. Sometimes if you use a sew-in without a fusible, the outside fabric of the project can look loose and floppy even if the bag itself has enough structure. Leaving a fusible interfacing still on your seam allowances can give your project a lot of structure to stand up on their own and make the seams stronger – like a frame for the bag. It basically makes your fabric thicker, stronger and easier to work with.
But, sometimes a fusible doesn't work well with your fabric and you can get little creases or stretches when it is cooled. To avoid this, always ‘press' rather than iron your interfacing on, and make sure to leave it to cool completely before lifting it up to use it.
Woven versus Non-woven
In a nutshell, a woven interfacing is just like a fabric – it's woven and has a grain line. A non-woven interfacing can be used in any direction, and is more like a paper.
Woven interfacing – your fabric should still look, feel and move like fabric, albeit a thicker one. A typical woven interfacing may take your quilting-weight cotton up to more the feel of a decor weight fabric. But it still feels like fabric.
You can also get a knit interfacing, called tricot, which can be used on stretch fabrics and may be used to prevent or restrict stretch in areas of the garment to prolong life and shape.
Non-woven interfacing – no grain line, like a felt or fleece. Can range from thin and wispy, through crisp and papery, through to stiff almost like card, or even lofty like a fleece or foam.
Pros and cons – the woven can be expensive and is typically only available in a much smaller range of weights, properties and thicknesses. It leaves your fabric feeling and behaving like fabric and usually fuses well without the wrinkles you can sometimes get from a non-woven.
The non-woven is available is a MUCH wider range and is much more affordable, and more easily available. However it can wrinkle or crease more easily. It can also tear (like paper) and makes the fabric feel less like fabric – which can be a plus depending on your project.
Examples used in the video
- Peltex – ultra-firm
- Decor Bond 809 – crispy
- Shape Flex 101 – woven
- Fuse N Shape – double sided firm
- Deco Fuse 520 – thin but stiff, almost plastic-like, or by the bolt
- Fusible Fleece 987F
- Headliner foam – also similar but more expensive is Annie's Soft and Stable
Amy Butler International Interfacing Guide – other country equivalents to the Pellon products shown
Pellon Crafts and Home Decor interfacing guide
Craftsy Blog – How and When to use Interfacing
Want to learn more about Interfacing and what goes on underneath your project? Check out this Craftsy class – Underneath it All: Guide to Interfacings, Linings and Facings.