If you have ever walked into a fabric store and walked over to the interfacing section only to turn on your heels and walk the other way – you are not alone!
Interfacing can be baffling – rows and rows of rolls and boxes that all seem the same but promise to do different things for you.
Over the next couple of blog posts we aim to demystify the world of interfacing, in particular, the world of fusible interfacing – who has time to sew interfacing in when you can iron it on!
Today we are going to focus on the basics and dressmaking interfacing, tomorrow we will look at craft interfacings – perfect for bags, baskets quilts are more!
The Science Bit!
Fabrics are made by weaving cotton threads together in a criss-cross pattern. The way each fabric is woven, the type and weight of the threads used, and the way you cut the fabric affects each fabric’s drape and stretchiness.
Interfacing disrupts drape. By understanding the different types of interfacing and their impact on your fabric, you can use this disruption to your advantage.
Fusible Versus Sew In
Interfacing can be sew-in or fusible, woven or non-woven. We recommend using fusible interfacing as it saves you a step in the sewing process, but if you want to retain the true drape of your fabric you will need to use sew-in interfacing.
Woven v Non-Woven
When you fuse non-woven interfacings on to your fabric all the little holes between the woven threads are filled in, the fabric becomes stiffer and the fabric’s natural drape is lost.
If you are only working on a small section of fabric, such as around buttonholes or on a collar, the loss of drape can be unnoticeable, or is the desired effect – no one wants a cuff that drapes, you want it to stand stiffly at the end of the sleeve, and the same is often true when making cushion covers, purses and bags, you use interfacing because you want your project to look smoother and stiffer.
In situations such as these, if the interfacing is going to end up between layers of fabric, or inside a cushion cover, there is no need to pay more for woven interfacing.
Woven interfacing comes into its own when you:
- want to retain the drape of your fabric,
- will not be covering the interfacing up with more fabric (non-woven interfacing can be damaged more easily and is less attractive),
- need to add a high level of strength through your interfacing – in a book bag for example.
Woven interfacings are created in the same way as fabric and so have their own natural drape. When you fuse these to your main fabric you retain that drape.
They are stronger than non-woven interfacings, are harder to damage, and are pleasing to the eye.
How to tell the difference in store? Woven interfacings are more expensive and so will have the word woven in their title. They have the appearance of very fine fabric with the pattern of the weave visible to the naked eye.
Getting the Weight Right
Non-woven interfacing is sold in three weights, lightweight, medium weight and heavy weight.
There are two factors to consider when choosing the right one for your project:
- The weight of your fabric – lighter weight fabrics such as silk, should be used with lightweight interfacing, regular cottons should be used with medium weight interfacing, home decor weight fabrics need heavyweight interfacings.
- How much control you need – although you should stick to the right weight for your fabric, you can move up the interfacing weights in order to increase the level of stiffness you want to add to your fabric, or down the range to minimise the impact of the interfacing.
The core interfacings for dressmaking remain light, medium and heavy weight interfacing, woven or non-woven. Whether you are strengthening a buttonhole or stiffening a cuff, these are the interfacings you will be directed to use.
However, there are a few newer interfacings that can take some of the hard work out of dressmaking that are well worth knowing about…
Waist shaper does what it says on the tin!
This fab interfacing comes in a number of widths. Simply iron it onto the back of your fabric and then fold the fabric along the perforated edges in the interfacing.
You will end up with a very crisp waistband, perfectly sized, and strengthened by the interfacing – we also use this one for bag straps!
Edge tape can be applied to any cut edges to stablize them, given them strength and stability during the sewing process and beyond.
It is very soft and low-stretch and is easily ironed into shape. It stabilises front edges, armholes and lapels on jackets and coats. Other application areas include pocket openings, vents, hems and other edges. Washable and dry cleanable.
Edge tape is designed for use on non-stretchy or woven fabrics NOT stretchy fabric and NOT around curves, for tapes for these fabrics and situations read on…
If you iron regular interfacings onto stretch fabrics they will most likely break and fall off in use. If you sew regular interfacing onto stretchy fabrics you may not find it breaks, but it will stop your fabrics from stretchy the way they are designed to.
This interfacing will stabilize your fabric’s structure whilst still breathing with the fabric as it moves.
Vilene’s Seam Tape is designed for use with stretchy fabrics, from velvet at one end of the spectrum through jersey and knit fabrics and all the way over to the Lycras at the other end.
Simply iron this tape onto the back of your fabrics around areas that will be subject to the greatest amount of stretch in daily life – around pockets, buttons and buttonholes etc.. and on areas of your garment that could become permanently stretched out of shape during the sewing process – typically around any curves, hems, and necklines.
Whilst I get why Vilene called this one bias tape, it is made from interfacing cut on the bias, I really wish they would come up with a better name as it can be off-putting and confusing!
Think of Vilene’s Bias Tape as a seam tape for curves or stay stitching on a roll!
You will often find patterns instruct you to ‘stay stitch’ areas of the pattern pieces. You do this because when the fabric is cut but not sewn it is prone to stretching, you may not even notice this stretch until you have finished your garment, but it can have devastating consequences, a neckline can be floppy or other parts fo the garment appear limp or out of shape, and there is nothing you can do at this point to rescue the garment.
Carefully stay stitching – sewing around the edges of the pattern pieces using a large stitch, close to the edge, will stabilise your fabrics and this is why it is recommended, but even the action of staystitching can result in stretching if you are guilty of pulling your fabrics through the sewing machine 🙂
Vilene’s Bias Tape is a heaven-sent little tape that does the job of stay-stitching for you. The tape is just 12mm wide and has a stay stitch running down one side. Iron the tape into place and your fabric will be stabilised and you will be ready to start dressmaking.