For those of you who do not know the back ground story behind this shawl, here are the Cliff Notes. I wanted to spin a random yarn to understand grist. I was then going to knit a shawl with the finished yarn. Well the experiment went horribly wrong and I did not have enough yarn to knit my shawl. I ended up with a yarn that had 28 WPI (693 YPP). To top it off I only had 8 ounces which gave me 346.5 yards.
This lead me to thinking. Since weave structures are linear, for the most part, could I weave the shawl using this yarn? I wanted a shawl that measured around 14" X 53". To knit one, I would need about 1022 yards. So, I began calculating warp & weft threads. I knew I would have to use another yarn for the warp but did I have enough handspun for the weft? I decided on tabby (plain weave) because I knew I needed to have a balanced weave structure to get more "bang for my buck." Not to mention the yarn is variegated and I wanted to show off the yarn. Here's how:
The Dream Shawl
A 14" X 53" plain weave at 20 epi at 20 ppi and no fringe.
I calculated how much warp I would need so I had to figure out the working length of my project.
To calculate warp:
project length + fringe + take-up (10% average) + shrinkage (10% average) + loom waste =Total Warp Length
53 + 0 + 5.3 + 5.83 + 36 (my loom leaves 1/2 yard (18") at front & back apron) = 100.13 Inches
Oh, I should say, use English or Metric calculations but don't mix them.
finished width + draw-in (1-2") + shrinkage (10%) = On Loom Width (OLW)
OLW x warp set (epi) = Warp Ends Needed
14 + 2 +1.6 + 20 (epi) = 352 Ends for my project
Now I convert my inches into yards:
total length (in inches) x warp ends needed = total warp (in inches)
total warp / 36 (36" in 1 yard) = total yards needed
100.13 x 352 = 35245.76
35245.76 / 36 = 979.05 yards needed for my project
With this information, I know I need to buy 980 yards of my warp yarn. This information is also useful because with these number, I can calculate my weft. This will tell me if I have enough handspun yarn.
To calculate your weft:
length of one weft shot in inches (width + 10%) x shots per inch (ppi) = inches needed to weave 1 inch of cloth
that number x inches in cloth (project length + shrinkage 5%) = weft needed for project
divide that number by 36 = yards needed.
15.4 x 20 = 308(105.13) = 32380.04 / 36 = 899 yards needed for my shawl.
Well, needless to say I could not get enough weft yarn out of the 8 ounces of handspun to complete the shawl of my dreams. I'm still going to weave a shawl out of this yarn. I just have to spin more yarn.
The Rebound Shawl
This shawl is 12" X 40" plain weave at 10 epi and 10 ppi, still no fringe.
I won't do the math again, since you have everything to calculate it yourself. But I will give you my answers:
Warp
total length: 80.4"
loom width: 15."
ends needed: 154
total warp: 12381.6" or 343.9 yards
Weft
length of one weft shot: 44"
ppi: 10
inches per inch: 440"
woven inches: 46.2"
total weft: 20328" or 564.66 yards
Even if I want to make the rebound shawl, I would need to spin another 5 ounces. To get enough yardage of weft. I hope this shows how difficult it is to spin now and match a project later. I could change the variables to make it work, but would I get the shawl I actually want? If you are going to spend the time making something, shouldn't it be something you really want? I had fun doing the math because I do love numbers!
