Commenting on a previous FoF about the Tree of Life SAL, Louise asked about Thread Heaven as a conditioner and we got onto the subject of using beeswax. I use it in goldwork to wax the threads used for couching or otherwise attaching the gold threads and wires, but I have never used it to smooth or tame wayward embroidery threads – I’ve always been slightly nervous of making the thread lose its sheen or look, well, waxy. However, I know of stitchers who have used it and they tell me it makes the thread more manageable without affecting the look.

Then a fellow-member of the Mary Corbet Facebook group asked about Silk Mill silks and when I mentioned how springy they are (I may have used the technical term “boingy”…) she expressed concern that they would not lie flat. Now I’ve only used the silk for split stitch and a bit of underside couching, where this is not a great issue. But in satin stitch, for example, it would be. I could feel an experiment coming up.

Earlier that day I had been re-arranging boxes and folders of designs, and in one of them there was a 3″ flexihoop and a piece of Normandy fabric which I’m sure had a purpose at one time, but as I couldn’t remember what it was I decided it would do very well for this experiment (which I wanted to be fairly quick). In one of the folders I also found a Mary Corbet freebie, the inner part of which was just right for trying out both line and filling stitches. I would work the lines in stem stitch and the shapes in satin stitch, half of the project with waxed threads and half with unwaxed (and unsteamed) threads.

I transferred the design standing at an awkward angle over my lightbox wearing the wrong glasses, which is why the lines are not the cleanest, but it’ll do. The experiment could have been done in one colour, but I chose two for a bit of interest, and also to see whether different colours would stitch up differently when waxed. I will readily admit that the combination is not very subtle, but the green is a colour of which I was sent a duplicate in error so I’ve got plenty of it, and the pink (which I chose based on the Silk Mill website rather than on their real-life samples) turned out to be much more shockingly pink then I had expected, so I’m unlikely to use it in any “proper” project.

I started with the outermost circle in unwaxed pink stem stitch. And I’d got about half-way round the circle when something I knew in the back of my mind suddenly came rushing to the fore: Silk Mill silk is Z-twisted! What does this mean? Well, almost all cotton and wool embroidery threads and most silks are plied in an S-twist, that is to say the direction of the thread’s twist is like the slanting middle part of an S, top left to bottom right. But rayons and some silks, including Silk Mill, are plied in a Z-twist, with the slant of the thread going bottom left to top right like the diagonal line of a Z.

At this point a polite non-stitching friend might say “ah”, displaying a mild interest and wondering whether the knowledge could come in handy in a pub quiz some time; a less polite one might opt for “so what?” And it is true that the difference is not always important. As I said, so far I’ve only used this particular silk for split stitch and underside couching, neither of which involves a great amount of twist (in fact underside couching involves no twist at all, as most of the thread lies flat of the surface with bits of it pulled through to the back at regular intervals by the couching thread). This means that the twist of the working thread doesn’t make much difference to the look of these stitches. But when working stitches that do incorporate a certain amount of twist, such as stem stitch or French knots, S-twisted threads and Z-twisted threads behave differently.

Take stem stitch. When working from left to right, the loop of working thread is always kept underneath the line of stitching. This results in that lovely rope-like texture which makes such nice crisp outlines. Were you to keep the loop of working thread above the line of stitching, you would technically be producing outline stitch – and the effect is quite distinct, especially when worked in a thread with a noticeable twist like perle cotton. This is because stem stitch twists the working thread in the direction of its natural twist, causing it to tighten up, whereas outline stitch twists it in the opposite direction, making the twist looser and the line of stitches much less textured.

At least it does when the thread is S-twisted; but if you have a Z-twisted thread, the effect is the opposite! So when the stitch instructions for a design say “stem stitch” but you’re using a Z-twisted thread, you need to work outline stitch, and vice versa. You’ll also have to twist the thread around the needle in the opposite direction when doing French knots or bullions, and it will make a difference to whipped stitches as well. You can see this effect in the picture below; you’d expect the green to be stem stitch and the pink to be outline stitch, but in fact it’s the other way round as they are worked in Z-twisted Silk Mill silk.

I’m rather pleased to think that my choice of silk is going to add another learning experience to the SAL: I’ll be able to point out in the blog which stitches need to be worked in mirror image to the usual instructions to get the same effect!

But back to waxing. The finished experiment shows stem stitch, unwaxed (pink circle), outline stitch, unwaxed (green circle), stem stitch, waxed (pink quatrefoil), outline stitch, waxed (green quatrefoil), satin stitch, unwaxed (outer pink) and satin stitch, waxed (green and central pink).

And the first thing that struck me was how much darker the waxed quatrefoil lines look than the unwaxed circle ones. Whether the coating of wax does actually make them darker or whether it’s because they reflect less light (or reflect it differently; there definitely seems to be less of a sheen), the effect is quite noticeable and would have to be borne in mind when choosing whether to wax. A second difference between the unwaxed and waxed threads shows up more clearly in the satin stitch sections: when waxed the threads look much more cord-like and separate – they don’t blend into one smooth surface nearly so well as the unwaxed threads.

That’s how wax influences the thread’s look; but does it make a difference to how it handles? Well, waxed it was a little more manageable with less bounce to it, although I was actually surprised how well the unwaxed thread behaved when I was doing satin stitch, especially considering that I hadn’t steamed them. On the whole I don’t think the slight improvement in handling is worth the loss of sheen and the loss of “spread” in the satin stitch areas. Yes, I can tell where I’ve waxed – and I won’t be doing it again.