Today’s blog post was originally a Pattern Spotlights newsletter, inspired by a reader question about whether wool would work for an upcoming design. Generally, I’ve never talked about the specific benchmarks and testing processes I use for designing knitwear, nor the implications that has for choosing yarn for knitting patterns. So, here’s a snippet for you!
(TL;DR — you’re safe to knit any of my designs in 100% wool, 50/50 wool/cotton, or 100% cotton. If you’re not, I’ll say so explicitly in the description so you have that data before you buy the pattern.)
My “Fabric First” Approach to Knitwear Design
I tend to design knitwear with a fabric-first approach. Over time, I’ve realised that this is my early family influences showing through. For as long as I can remember, I’ve been fondling fabric in shops, scrunching it and shaking it, folding it and draping it, all to see how I can get the best out of it, should I buy it. Trousers or skirt? Pleats or gathers? Twill or plain weave?
And I built up a fabric stash based on:
- Fabric that was perfect for a currently unknown pattern; and
- Patterns that would be perfect for a currently undiscovered fabric; and…
…that one day, this Venn diagram would form a perfect circle. That was the plan. (I stand by that plan, even though it has largely failed. That’s foolish hope for you!)
But when I fell in love with knitting after false starts in childhood — and then designing clothes — one of my absolute, hands-down favourite things about knitting is that you can make your very own fabric. Isn’t that AMAZING?
The Life-Changing Magic of Designing Fabric
I thought so, and still do. I’ll never be a weaver. And I love this about knitting more and more each day. The Venn diagram problem doesn’t exist (at least, not on the same scale) because I can control the weight, drape, structure…so many fabric properties. It was control and empowerment I didn’t have at the fabric shop. And I loved the idea of being free of the disappointment of finding nothing suitable for a pattern — it didn’t matter whether it was mine or something I’d bought — and going home dejected and frustrated.
The only thing I had absolutely no say in was the fibre composition and yarn construction (3ply, roving, etc). I’m all over the former; the latter has a bit of catching up to do over the course of my lifetime, and I am always learning. But this is supported by swatching, which I absolutely love on the design and fabrication fronts. It’s where I create the fabric, which includes the stitch pattern, choose the needle size, and evaluate the swatches to see what works best. This means that I can give anyone who asks reliable information about choosing yarn for my knitting patterns.
The Fibre Families I Test For Every Design
I have three broad groups for fibre, and subgroups within for testing everything I design. They are:
100% protein fibres (animal hair)
This is animal hair like wool and alpaca. This is then broken down into superwash and non-superwash for wool. It also includes wool/alpaca blends and combinations of various sheep breeds.
50% protein / 50% cellulose
Half and half is the target, but I can’t always get hold of it. But I always get something to see what the combination means for my design.
100% cellulose (plant based)
This is plant fibres like cotton, linen, hemp, tencel. I like to get something from the stem of a plant (in that list of examples, everything but cotton) because cotton is a seed casing, and fibres behave very differently depending on which part of the plant they came from.
Why Swatching Matters For Knitters: The 20cm Rule
Everything I’ve ever designed has had a swatch at least 20cm by 20cm (8in by 8in) in each of these three categories. I don’t always get to all the subs, but I can assure you that three is the barest minimum. And I dovetail the experiments with existing knowledge across the board and other, older garments. This is why I will never give away samples, and aim to knit as many as possible myself. Longitudinal data is precious because you can’t mimic the passage of time. How have the designs lasted? How did I finish them? How were they cared for?
The goal is to be able to recommend something from each of the three groups. I try my best to design knits that are versatile and robust across all three fibre families. That applies to, at this time and for the foreseeable future, everything you see in the shop. I usually get my way, and have binned designs if they fail here, but if I were ever in a bind or torn up about a design, I would reflect on what needs to change, and come up with a new or alternative design that suits that fibre and fabric better.
Wrapping It Up | A Quick Yarn Substitution Checklist
This is how you can use this research for your own projects or choosing yarn for knitting patterns. You can build up swatches of your own or refer to existing garments you’ve knitted.
Quick Guide: Can I Swap the Yarn?
- Check the description: Does the designer mention fibre tests?
- Protein fibres = warmth and memory.
- Cellulose fibres = drape and weight.
- Always knit a 20cm swatch to test the fabric feel before starting.
As always, I hope this was helpful! Please bookmark, share, or pin this post if you found it helpful. And to go further with your fabric choices and make sure they suit you, you can download my free guide below.