WARNING! This post is loaded with math. Read at your own risk.
I have learned a lot from dissecting my Shetland Fair Isle swatch. And the funny thing is, the process is so logical and so simple, that I wonder why I didn't figure it out for myself.
The Fair Isle pattern is from Anne Field's The Ashford Book of Spinning. The actual sweater in the book is a lovely bulky pullover knitted at 4 stitches per inch. Since I want a cardigan at 6 stitches per inch, I will need a different sweater pattern, but I've always admired this pattern.
For my swatch, I had trouble following the black and white chart, so I finally colored it in. There are 16 rows in one repeat, using nine colors. To figure out how much of each color I would need, I frogged my swatch and measured each length of yarn in one of these pattern repeats. The swatch was 3.5 inches wide, so I divided the inches of yarn I used for each color by 3.5 to find inches of yarn I would need to knit for one inch of the pattern. I could then multiply this by the size I wanted for the cardigan (both body and sleeve width), and multiply that by the number of repeats I would need for the length of each.
Formula style, here's what I did:
Inches used ÷ swatch width = Yarn for 1" width
Yarn for 1" width x Sweater circumference
= Inches needed for one pattern repeat.
Yarn needed for one pattern repeat x number of repeats in sweater length = amount of yarn needed for that cardigan piece.
This amount is in inches, so divide by 36 to get yardage.
Calculate yardage for each sweater piece and total these for approximate amount needed for cardigan. Round up generously.
So, using the bottom (yellow) color on the chart as an example:
15" yarn used ÷ 3.5" = 4.3 inches used in one inch
4.3" x 42" circumference = 180.6"
180.6" x 10 pattern repeats = 1806"
1806" ÷ 36" = 50.17 yards
Rounding up, I need 51 yards of that color for the body of the sweater.
Next I'll calculate the amount needed for the sleeves as well. Adding these two together will give me the approximate yardage I'll need of that color.
I'll do the same for each of the nine colors used in the pattern, and then figure out what I need for all the ribbed edgings. From there I can choose the Shetland colors based on the amounts I have of each.
Whew! Did I say this was logical and simple? Well, maybe not simple, but it is logical. Even so, I feel better having at least some idea of the amounts I need. At the moment I'm finishing spinning the leftover Shetland rovings, plus some extra of Nikki's fleece that Cathy sent. After that, perhaps I can actually get started on the sweater.
Posted 16 Feb. 2008 at http://leighsfiberjournal.blogspot.com
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