Friday, November 3, 2017

Finally! Spinning to Grist.

 My previous 2 blog entries document how I have explored ways to achieve specific grist for my yarns. I have found that yarns knit more like their grist and less like their diameter, if the two don’t match up. Many spinners spin dense yarns, maintain that is how it is and don’t bother to adjust their spinning. I want yarns that look, feel and behave the way they ought to, in order to get gauge on a knitting project and for the fabric to feel and to drape appropriately.

 I thought I had a method figured out until I reviewed a video I had purchased a few years ago by Patsy Zawitoski called “Make That Yarn”. What I had initially gotten out of the video was that I needed to get the same twist into my yarns as the one I am creating. What I had totally missed or worse, ignored, was her method in measuring and recreating grist. She, too, is adamant that grist is something very important in a yarn and a characteristic that can and should be controlled. Probably it was her use of a McMorran balance that put me off – they are single purpose, pricey, generally hard to find and fiddly to use. So, idiot me, skipped over that part in the video – and it is the main point!
However, she demonstrates an easy way of determining how much fiber you need to use. She laid out a singles that had balanced on the McMorran scale. Then she measured out an equivalent amount of fluff and attenuated it out to the same length as the singles. This is the answer I was seeking.
What I do is calculate how many mg of fluff needed for 1 meter of singles at a specific grist. Then I weigh out that amount and attenuate it along a tape measure. I wrap part of this onto a card in its fluff state, some in a tensioned state and finally some with a bit of twist in it. That gives me the visual cues I need to make sure I am drafting about the right amount. Finally I do some ply backs, measure their lengths in decimal meters and divide that length its weight in decimal grams. Once I get a plyback that matches the grist I am after, I attach that to the card as well. At present I am trying to build in about 7% loss of length for wool after finishing, which is about 0.2 m/g grist change.

 During spinning, I regularly do short plybacks to compare to the card. I occasionally make long, measured plyback grist tests to make sure I am still on target. Getting this part done doesn’t take much time and is easy to do. However, drafting consistently is still a skill that will require MUCH practice. The fibers themselves as well as the preparation are certainly factors. However, I am finding that I am within reasonable error of achieving the grist I have set out to make. I am also finding that the final yarn diameter is usually correct for the grist. Of course, I have to also work on consistent twist in the singles as well as the plied yarn – but those are easier to achieve if the draft is even.

 It is also illuminating to see how little difference in amounts of fluff makes a major change in grist!

4m/g on the left, 3m/g on the right. The difference between the two at the bottom per meter.

To figure out how much singles grist you need:

 Final grist x number of plies = singles grist in m/g
  1000/singles grist = mg in one meter of singles. ( Or use 1 instead of 1000 for decimal grams)
 Here's a little table for singles, 2 and 3 ply, at various grists.

How do you know what grist to use? If this is fiber that you have not used before, then some basic sampling before even worrying about grist is in order. How does it draft? How much twist is best? What kind of draft is best? What would it best be used for? How many plies should be in the yarn? I often use a hand spindle to explore a fiber's properties. Once I know what I would want to do with it, I research typical grists of this fiber in commercial yarn, if available. Otherwise I might take some measurements of my samples to get a sense of a good grist to use. After that, I spin some small skeins and knit swatches before continuing to spin for a project.

I am now working on a little project to spin Cheviot fleece at a variety of grists and number of plies. I am also knitting swatches with each sample yarn. The next post will be about that project.

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