Knitwear Design 101 | Fabrication, part 2

Welcome to part 2 of my Fabrication mini-series! In Fabrication part 1 I discussed fibre type, staple and yarn construction.  This month I’ll focus on fabric construction and how construction techniques affect knitted fabric in general terms.

Knitted and crocheted fabrics fall into the broad category of stretch fabrics, which also includes tricot or warp-knitted fabric.  Warp knitted fabric can be seen as a halfway house between woven fabrics and weft knitted fabric – which is what hand knitted fabric is.  In weaving, the weft yarn is that which crosses horizontally; in hand knitting, the working yarn also follows a horizontal path as the knitters works each row, back and forth, changing needles.  By contrast, warp knitted fabrics consist of several lengths of yarn – one per stitch – which are mounted onto a specialised machine in a way similar to that of vertical warp threads on a weaving loom.  To form a knit fabric, the threads of warp knitted fabric interlock in a zigzag motion.  Stretch fabrics bought for dressmaking are highly likely to be warp knitted fabrics, and the difference between the warp and weft knitting is important to note if you’re also a dressmaker or fashion student with experience of sewing stretch fabrics.  If this description fits you, please don’t fall into the trap of thinking that your knowledge is completely transferable!

Weft knitting on the left; warp knitting on the right. Image sourced from researchgate.net (Raz 1993: 17)

Further, there are two general types of stretch:

  • Mechanical stretch – which all stretch fabrics have due to their interlaced loops;
  • Fibre stretch – the inherent elasticity of the yarn or fibre knitted into a fabric.

Warp knitted fabrics are more durable and elastic than weft knitted fabrics produced by hand knitters, and this relative delicacy means that even greater care must be taken over fabrication.  Understanding how both types of stretch interplay and interact is important not only for deciding which yarn to choose for your design or project, but also for understanding how the knitted fabric created will differ from yarn to yarn, knitter to knitter (yes, I’m talking about tension or gauge!), and technique to technique.  As many knitters discover, the fabrication changes depending on whether you are knitting cables, rib, lace, or stranded colourwork.  Here’s a Venn diagram showing how these three properties of fabrication come together.

Venn diagram depicting contributing factors and design considerations of fabrication. Created by the author.

You can see that yarn choice is the first part of the equation – but the fabric you create in the chosen yarn can vary widely – or even wildly.

Construction techniques

Here I’m referring to ribs, cables, lace, stranded colourwork – the whole arsenal of knitting techniques.  It cannot be denied that the resultant textures are completely different; one good exercise is to knit all of them up using exactly the same quality of yarn and observe how the swatches behave.  As you might gather, they’ll all be utterly unique – but the control, or restricted yarn choice, will tell you something about how each technique affects the fabric.  Ribbing draws fabric in horizontally; lace has a tendency to spread horizontally – how much is usually in direct proportion to the quantity of eyelet holes and their proximity to the corresponding decreases; stranded colourwork compresses the stitch tension due to the floats at the back, and this results in more square stitches, or a looser row tension.  These general descriptions are in relation to a stocking stitch swatch – and now you have one reason why the stocking stitch gauge swatch is so important for yarn substitution!  It should always be included in the information at the front of each and every knitting pattern, and provides an important baseline for the person knitting the pattern. 

Even more importantly, designers should swatch in stocking stitch BEFORE experimenting with any stitch pattern or technique.  Yes, you are likely to reduce the needle size for ribbed welts, but the stocking stitch swatch will indicate whether you should go down one or two sizes to get the elasticity you want – and in turn, that can vary depending on whether you’re fitting a cuff or a bottom band.  Different degrees of clinginess might be needed (or appreciated) depending on the area of the body.  Further, you may decide not to have a ribbed welt at all, or reduce the depth, based on the information provided by your swatches.  You’ll have at least two by now: one in stocking stitch, one to test out the ribbing.  And if your main pattern is in neither of these textures, you’ll then need to decide whether you go with the manufacturer’s prescribed needle size, or go up or down a step.

Two knitted swatches – one ribbed, knitted in a sage green; one in stocking stitch, knitted in a pale pistachio green.

What I hope I’m conveying is that fabrication is an inescapable part of knitwear (and crochet) design.  You need to consider it in tandem with conceptualisation, because it is the portal through which mind (your imagination) becomes matter (your physical sample).  Unlike design for woven fabrics, a chunk of the work hasn’t been done for you; nor do you have the same limitations of choice when sourcing fabric.  You’re creating the fabric from scratch. 

A fashion design team may, for example, have a silk challis in mind, but the search for just the right one for their clothing design may be challenging.  A silk challis will have general characteristics (lightweight, smooth, soft), but these will be relative to the manufacturer’s limitations and the design team’s expectations.  Knitters and crocheters also have to carry out research and source yarns, but the extra time needed for swatch development is more than compensated for by the fact that, once a suitable yarn is found, the only thing between it and the ideal fabric is needle/hook size and experimentation.

The experimentation you do at this stage of design development should be passed onto knitters of your pattern once you’ve made your final decisions.  You might have settled on a yarn and fabric that suits your purposes, but it may not suit your knitters quite as well.  If the yarn is not available, or if they live in a completely different climate, knitters of your patterns will greatly appreciate a few words from you about switching things up.  It will reaffirm or add to knowledge and experience they already have, and give them more confidence about using a particular yarn.  You’ve had the experience of developing and realising the design, and your knitters deserve to benefit from that.  They’ll be expecting to make something that looks a lot like the beautiful picture you put on the cover, so help them out as much as you can.

A final word on scale

If you’ve been reading my blog for a while, or remember the From Needle to Needle series I wrote in earlier 2021, you might gather that I have FEELINGS about sample knitting.  If not, I’ll restate them here: Sample knitting is part of the design process, and if you outsource it – whether through test knitting or a paid sample knitter – make absolutely sure that you collect valuable information from your sampler(s) or testers, especially if you’ve stated that they don’t have to use your preferred yarn.

Why?  Because swatches are clues or starting points only.  Your final sample, especially if it’s a garment, is going to be significantly larger than the squares you knitted at the beginning.  Experience and deduction are extremely helpful, but scaling up the information and techniques in your swatches – not to mention the combination of different stitch techniques – can still surprise you.  Swatches do not have seams; nor do they have collars attached, button bands picked up, or bodies wearing them.  You may find yourself altering construction or finishing techniques once the sample has been completed, which may mean altering the draft pattern.

I’ll talk about finishing next month in the final fabrication post, part 3, but until then, let me know what you thought about part 2!  I’m especially interested to know whether anyone appreciates notes from the designer about yarn information, or whether you’re happy to wing it 😉.

6 Comments Add yours

  1. Jo Cohen says:

    Hiya
    As a long term knitter, but only really starting to ask questions as I knit different types of garments with different yarn this is fascinating. What immediately springs to mind is that this is like Theory in music. I could easily read piano music and progress through the early grades, but by Grade 5 you had to do Grade 5 theory to move on. This information is knitting theory and really enhances my ability to understand what I am knitting and how to choose projects.
    Thankyou

    1. Hi Jo,
      Thank you very much for saying that! I especially appreciate your comment because I’m trying to get back into piano playing at the moment 😃
      I hope part 3 will be helpful too; it’ll be out on the second Wednesday of November if you want to check back.
      Natalie x

  2. Meredith Coelho says:

    I rarely use the same yarn the designer did, and I really appreciate notes from the designer about qualities to look for in a substitution. I always swatch, but it can be hard to extrapolate to a garment.

    1. Thank you Meredith – and yes, reading and interpreting the swatch is tricky! I still feel nervous sometimes, especially if I’m experimenting with a design.

  3. Sharon says:

    I’ve finally come round to knitting swatches – which was just as well with one project this year where I was using an Aran weight yarn in a DK pattern (or was it t’other way round? Whatever.) And that was using wool, let alone changing the yarn type.

    Even properly swatched, the actual knit turned out So Much Larger, that I had to do a quick hack (not literally), readjust the arithmetic, and knit a smaller size in the pattern. Quite how that holds up when I get to the yoke . . . I’ll find out!

    Thanks for the detail you put in. I know it makes sense, I just want to get on and knit! But First I WILL Knit Swatch(es), if nothing else I can make a blanket or something eventually.

    1. You’re very welcome Sharon – and yes, I know what you mean about the collection of swatches! I have a huge tub full over here 😉

Leave a Reply