One of the things that mystifies new weavers is the phenomena of draw in.
They weave a nice fabric with lovely straight edges, and when it comes off the loom and away from tension, it gets narrower and shorter. Then when it goes into the water for wet finishing it gets even smaller. What happened?
When you weave fabric, you interlace three-dimensional "rods" of warp and weft.
While the web is on the loom, the warp threads are held under tension. This tension holds the warp threads straight and prevents them from bending over and under the weft. Note how, in the diagram below, the yellow warp threads form a straight, horizontal line.
Once tension is removed, the warp threads relax and begin to bend over and under the weft threads. This relaxation increases when you wet the fabric.
The angle of the weft's intersection with the warp, which is acute in the diagram above, flattens out as the warp softens and deflects over and under the weft. At the same time, the weft is also relaxing and softening around the warp. After wet-finishing, instead of holding each other at arm’s length, the warp and weft now embrace each other.
See now how the yellow warp threads have been deflected by the weft and no longer form a straight line?
[Editor's Note: If you are a knitter, wet finishing in weaving is the opposite of lace blocking. Instead of starting with something crumpled-looking and blocking it under tension, you are starting with something under tension and using wet-finishing to get it to relax.]
Some weave structures, for example huck lace and waffle weave, have floats that enable the warp and weft to slide out of its rigid, perpendicular grid once the tension has been removed. When this happens, you can create three-dimensional effects (like the dimples or pockets in waffle weave.) The trade-off is for this texture is even greater draw-in as the threads deflect above the flat surface of the cloth. This is why a structure like waffle weave might have a draw in of thirty percent or more. In general, the longer the floats, the greater the texture of the finished cloth, and the more draw-in it will experience.
Draw-in is also affected by how densely the fabric is sett and woven, because in dense fabrics the threads are less able to move around during wet finishing.
Because plain weave has the maximum number of interlacements (and thus no floats) it will draw in the least of any weave structure.
Twill weaves have small floats, so they draw in more than plain weave. Some twill variations shrink more during finishing than others (depending on the length and placement of the floats.)
When weaving both plain weave and twill in a fabric, the fabric has no choice but to draw in more in the twill areas that the plain weave areas.
You might take the web off the loom with perfectly straight selvedges, but after wet finishing it, discover that the edge is scalloped.
This can be a disapointment or—if done intentionally—a design element.
You can create interesting textiles by understanding what is happening in the cloth and controlling it. The scarf in this project has a delicately scalloped edge: part of the design is woven in plain weave, and part of it in a twill variant.
Loom with four or more shafts.
Using one 4 ounce skein of hand-painted Bambu 7 yarn and a strand of Bambu 12 black, I wound a warp with two strands at a time. This means that each cross held two threads. When winding two threads together like this, I keep a finger between the two strands during winding so they do not twist around each other.
The warp was wound 3 yards long, and 8 inches wide (160 threads total.)
Warping the Loom
I threaded the loom in straight draw, randomly picking either the hand-painted Bambu 7 or the black Bambu 12 from the doubled-thread cross.
I always begin from the shaft furthest to the back of the loom and work towards the front. I also dress the loom back to front, beaming the warp, then threading the heddles, sleying the reed and tying onto the front apron.
|length (inches)||width (inches)|
|After wet finishing||
(Width is approximate – the half basket areas were slightly narrower than the plain weave areas after wet finishing.)
Plain weave alternating with half-basket weave.
The weave draft above shows six picks each of plain weave and two of the twill treadles. I alternated twenty picks of plain weave and twenty picks of half-basket weave in the actual scarf.
Note also the transition between the two weave structures. It will appear "odd" on the loom, but after wet finishing everything looks fine.
Regenerated bamboo is slippery and since the area that is woven using the two twill treadles (sometimes called “on opposites” or half-basket weave) will allow the weft to slide and compact more than the areas of plain weave, the stripes of plain weave and half basket weave will not be equal in length.
The twill will naturally weave at a higher pick-per-inch than the plain-weave sections. Rather than trying to maintain the same number of picks per inch throughout the entire textile, keep the picks per inch within each weave structure consistent.
It is also important to advance the warp often. Each loom has a "sweet spot" where the beater strikes the fell at the optimum angle (ie: perpendicular to the warp.) If the fell line is too close to the reed, the angle of the open shed and the tension on the threads becomes greater and the selvedges can begin to deteriorate, eventually leading to broken threads.
Since plain weave is very stable, I began and ended the scarf with twenty picks of plain weave. The fringe was twisted and then the scarf was wet finished in the washing machine. I added a couple of towels to help balance the washing machine tub.
I set the machine to warm water wash and rinse and selected the gentle wash, gentle spin cycle. The scarf was then tossed into the dryer and removed when it was dry. Trimming the fuzzy ends of the fringe completed the scarf.
When attempting to create a special effect that relies on draw in or shrinkage, it is always a good idea to sample first. An easy way to do this is to make your warp a little bit longer than your project requires, weave six inches or so and then cut that off and wet finish the sample. If you don’t get the results you want, analyze what needs to be changed and try again.
Sometimes you need to change the sett, sometimes the weave structure, sometimes the weft color or size isn’t quite right. You will only know for sure after you have wet finished the fabric.
Laura Fry has been weaving professionally for more than thirty years. In 1997, she was granted her Master Level by the Guild of Canadian Weavers. In 2004, she self-published a book, Magic in the Water: Wet Finishing Textiles. Her website is full of articles and tips about weaving.