The importance of 50/50 © Jane Stafford Textiles
One of the first things I learned when I started sewing as a young girl was how important it was to lay your pattern pieces on the straight grain. This was important because the bias in the garment would then be ‘good’. I didn’t really understand bias until I was a weaver. When I studied textiles in school I learned about the wonderful phenomenon of 50/50. 50% of the the threads in 1 inch are in your warp and 50% of the threads in one inch are in your weft. This creates perfect bias. This is one of the first things I teach in every one one of my workshops and I do it on the blackboard just like this:
In this drawing I have drawn some lines that represent a blown up piece of cloth. The warp threads are the vertical lines and the weft threads are the horizontal lines and the negative space in the middle is a perfect square. When you plot the intersecting points on the diagonal you have a 45 degree angle. They are the pink spots with the big arrow going through. That 45 degree angle is where bias comes from. If you pulled on the arrow points your fabric would stretch. If our sett isn’t correct at the start of weaving and we just weave willy nilly and beat away not paying any attention to the placement of our weft…. and we don’t pay any attention to the negative space in our cloth… we will end up with either of the two options below.
In this drawing my sett was too open and therefore my weft keeps moving down no matter how light I beat or I haven’t paid any attention to my negative space and I’m merrily beating the living daylights out of my cloth. The diagonal line is now low and I have lost bias.
In this photo my sett was too close and even if I beat lightly the angle is high. In both cases I have lost my optimum bias and therefore I’ve lost my optimum drape. SO….if you want to weave cloth that has yummy, scrumptious drape, is stable and has great hand you need to pay attention to your epi. The only way I know how to do this is to sample. I wrap my ruler thinking about what my weft will be and I leave a space between my wraps that represents the weft yarn and I also leave a little extra space in the wrap imagining how I’m going to finish the cloth. If it is wool and I know it is going to bloom a lot then I leave extra space for the yarn to bloom. If I know that I’m going to wash the cloth 10 million times and throw it in the dryer I leave extra space for that to happen so that when the cloth is finished it still has great drape and hand. SO many weavers wrap without thinking about how the cloth will drape, they wrap without imagining the end product. When all is said and done we end up weaving cardboard. Once it is cardboard, it’s cardboard! As I said in the previous post I work with the same yarns over and over and over and I know their properties. I start with what I think it should be sett at and then I weave a piece perfectly squared, cut it off then resley at a different sett either more open or more closed. I weave that piece perfectly squared and cut if off, and then resley in the other direction and weave it perfect squared. In the end after I have washed all the samples I have something to compare. If you don’t try different setts how to do you know for sure that something else couldn’t be better. Often weavers will ask me what difference can 1 or 2 ends make, I mean reaallly! Well, I think about it this way. If the cloth is balanced you are talking about 1 end in the warp and 1 pick in the weft. That is 2 threads in a square inch. If you are talking 2 ends per inch in the warp and 2 in the weft that equals 4 threads in a square inch. A square inch is around the size of a postage stamp….that is quite a few threads when you stop to think about. And then, there is the big picture……..2 ends per inch difference in the warp equals 4 ends total in a square inch and if your piece is 45” wide and 45 inches long you are looking at 180 threads in or out of the 45” piece of cloth. Now you can really appreciate how important this is. Below are some samples of a cashmere yarn woven in plain weave. Each one is stunning, each one is different and I can choose any of the setts based on how I want the finished product to behave. If I hadn’t done the sampling at the outset I wouldn’t have this information. If I want I fine gossamer scarf I choose the most open sett. If I want a fabric with more weight I choose the middle sett and if I want a fabric that I’m going to turn into a jacket, I’ll choose the tightest sett. And then, I do it all over again in twill. This is where all the setts on my master sett chart came from.
Once I have this information I have a canvas. On that canvas I will lay graphic lines and then I will fill in the colour.
But before I do that I’ll sketch, sketch, sketch. So go get a little sketch book and buy yourself some nice pencil crayons and next week we will start drawing.