Try Sizing On for Size

To use a softer yarn for warp, I turned to an old technique: applying a coating to minimize the effects of abrasion.

Anne Merrow May 24, 2022 - 6 min read

Try Sizing On for Size Primary Image

A few packets of unflavored gelatin transformed a yak/silk blend from soft and silky to stiff and linen-like.

"People used to size everything in the 70s, but nobody sizes any more," a friend remarked a few weeks ago, when I told her of my plan to try sizing some laceweight knitting yarn that I really wanted to weave on my rigid-heddle loom.

Inspired by Rachel Simmons's Sand and Sea Wrap (Little Looms 2019) and Deborah Jarchow's Travel Shawl (Handwoven May/June 2018), I imagine a very fine and drapy shawl. To sett it close enough on my rigid-heddle loom, I'll need two 12-dent reeds. The yarn I fell in love with is a fairly low-twist 50/50 yak/silk blend—strong, but I'd like the blooming to happen when I wet-finish it, not when I'm weaving. That's the perfect use for sizing.

The idea behind sizing is to coat the yarn (usually warp, but sometimes weft too) with a substance that will make it a little stiff and compact when it dries. I've heard of weavers using hairspray or spray starch on a sticky warp to help guide it through the heddles, but then you have spray starch or hairspray all over your loom, your lap, and your weaving room. The method I decided to use was to wind skeins, dip them in sizing, and hang them to dry.

Sizing this way is an intentionally temporary solution; when the textile is wet-finished, the sizing washes away. In the end, you'd never know the sizing was there.


So I asked my spinner/weaver friends: What do you use for size? They all came back in unison: Gelatin! There is a variety of recipes using flour and milk powder, but gelatin seems to be the least messy and prone to spoiling or critter attacks.

Sizing is prone to critter attack

Gelatin didn't attract insect or rodent pests. Drawn by moving yarn and sheer excitement, though, larger pests did prove to be a hazard.

Sizing with Spinners

Most of what I read about sizing comes from spinners who weave. Stephenie Gaustad wrote an article for Spin Off Spring 2018 about sizing her energized singles handspun yarn, and I generally followed her process. Sara Lamb wrote about sizing in her book Spin to Weave, including plans for a blocking reel. And more recently, Devin Helmen has refined their sizing process as they weave linen and hemp.

So why do I hear spinners-who-weave talk about sizing and not weavers (at least, not the weavers I know)? I suspect it's about the yarn. Many weavers reach for a fairly narrow range of yarns: high-twist, smooth, wound on cones, possibly still with spinning oil in them. The latter two factors compress the yarn and suppress fiber halo until they're wet-finished. (I'm out on a limb here, so if I'm missing something, do speak up!)

On the other hand, spinners may create yarns that are deliberately unbalanced and overtwisted, highly textured, singles, and more—all of which can be gorgeous when woven but need a little help getting through the heddles without being shredded. I've chosen a commercial knitting yarn that is smooth and balanced, but I do have a little worry that the luxury fibers will escape the twist, fibrillate, and shred themselves on the way through the heddle.

Some expert weavers have told me that a rigid heddle abrades the warp more because the plastic edges of the holes scrapes at the yarn more than a traditional harness loom. (Of course, only the hole warp threads get that kind of abrasion; the slots are much less touched.) On the other hand, I've heard the theory that the plastic of a rigid heddle is far gentler than metal heddles. In any case, I am a happy rigid-heddle weaver with some fairly special yarn, so I decided it was worth a try.

Gelatin Solution: The Learning Begins

When you pour powdered gelatin in water, stir it right away. Don't dump it in, get distracted, and then try stirring frantically a minute or two later. You will be picking boogers off your yarn for days. (Sorry. Crass, but true.)

I sized the 3 skeins I intended as the main warp colors, plus a little of the weft yarn that I plan to use as a selvedge. Devin, Stephenie, and Sara all used some kind of blocking device as they let their yarns dry, but it wasn't necessary for my project. I snapped the skeins to keep them tidy, hung them over a shower rod (covered in plastic wrap), and turned them every few hours. As I turned them, I tugged the skein apart as much as I could, rotating each skein and separating the strands from their neighbors. (This is where I picked off most of the gelatin boogers.) In arid Colorado, they dried in a day or so.

Now it's time to put them on the loom and weave them... I'll keep you posted!