Saturday, April 28, 2007

And the Next Wood Grain Scarf...

Scarf #3 is woven. The weft was dyed with Koa wood chips (see Playing with Sawdust a couple of posts back).

On to the next, this one with a logwood grey weft and another completely different treadling.

Friday, April 27, 2007

Next Wood Grain Scarf in the Queue

Scarf number 2 in the wood grain series is woven. Here's what it looks like as it travels under the loom to the cloth storage beam:

The weft is the skein I dyed with mulberry wood chips from DH's wood shop and quebracho red extract from Earthues. See Playing with Sawdust a couple of posts ago for pictures.

Tuesday, April 24, 2007

Jacquard Fever

Last weekend was the CNCH annual conference, held this year at Asilomar Conference Grounds in Pacific Grove. I took a 2.5-day workshop with Alice Schlein on using Adobe Photoshop as a design tool for dobby or jacquard weaving. The good news is that I learned a lot and now have some new design tools. The bad news is that I now have a serious case of Jacquard Fever. Gotta have one.

To reinforce what I learned, I spent some time today working with a photograph of some dogwood trees in bloom taken by my sister Barbara. Here's a portion of the photograph, in the original colors:

After a little time in Photoshop, working with brightness/contrast and color levels, I indexed the photo to 7 colors. Seven is the right number if you intend to weave a picture using shaded 8-end satins because with 8-end satins there are 7 possible combinations: 1 thread up and 7 threads down (written as 1/7), 2/6, 3/5, 4/4, 5/3, 6/2, and 7/1.

For the purpose of this example, assume that the warp threads are black and the weft threads white. So a thread "up" means that where the warp and weft intersect, the warp is on top of the weft, so what shows is black. Conversely, a thread that's "down" means the warp is under the weft, so what shows is white. So 1/7 satin is mostly white, while 7/1 satin is mostly black.

Okay, here's the photo in 7 colors (they all happen to be shades of gray):

Then, I assign one of the 7 satin patterns to each of the 7 colors by "filling" the color areas with the weave pattern. I assign 1/7 satin to the lightest color, 2/6 satin to the next lightest, and so on to 7/1 in the black areas. Here's the result, all ready to weave. Each pixel in the photograph has become a point where a single warp and a single weft intersect, and if an area has mostly warp on the surface, that area is dark; if an area has mostly weft on the surface, that area is light. Note that there aren't any completely white areas in this version, or any completely black areas. That's because if no threads are "up" or if no threads are "down" you don't have cloth, just a mess of tangled loose threads. There has to be at least one intersection (or transition from "up" to "down" or vice versa) in that group of threads to make woven cloth.

Now, if only I had a Jacquard loom so I could weave the photo for Barbara's birthday present...

In the meantime, I'll do some practice on the techniques for creating designs for my 24-shaft dobby loom in Photoshop, and if I come up with anything that looks interesting, I'll post pictures. Plus, there are still four wood grain scarves waiting to be woven.

First Woodgrain Scarf Woven

Today, I was able to get back to the loom and weave the first scarf in the woodgrain series. Here's a picture of the scarf when I had woven maybe 600 picks (a pick is one pass of the shuttle).

When I'm weaving, you can only see about 6 or 7 inches of the cloth, because the fell (the most recently woven pick) is pretty close to the point where the cloth wraps down and around the front beam. So here's another picture taken when I'd woven almost the whole scarf, and I'm looking at it under the loom, where it reaches back to wind onto the cloth storage beam (to the right of the picture). You can see more of the pattern from this angle. The light for this picture is late afternoon sun, shining directly in the floor-to-ceiling windows at the back of the loom, so the color balance may be a little different from the picture taken at the front of the loom.

The weft for this scarf is the yellow skein that I dyed with Eucalyptus leaves. You can see pictures of this weft and the others I'll use for the remaining scarves a couple of posts earlier in the blog. The overall coloration of the cloth is heavily influenced by the two warp colors (tan and brown) because the warp is a slightly thicker thread, and is sett quite closely, whereas the weft is a finer thread and woven with fewer picks per inch than the warp has ends per inch. So the woven yellow doesn't appear nearly as yellow as it does when all you see is the weft skein, unwoven.

Because the yellow weft and the tan warp are close to the same value, the net effect is a light color wherever the weft and the tan warp are on the surface of the cloth, and a darker color wherever the weft and the brown warp are on the surface. There are also areas where the yellow weft predominates, but the result is yellow with tan and brown specks, not solid yellow. Optical blending merges the colors of the individual threads into shades in between the three thread colors, much as the dots in a pointillist painting blend into a solid color when viewed from a distance.

I'm quite pleased with the woodgrain effect in the cloth, and am looking forward to seeing the others in the series as they "grow." It takes me about 4 hours to weave one scarf. This particular pattern has about 2400 picks. Some of the time I'm throwing the shuttle at 60 picks per minute, but in between bouts of weaving I need to stop to wind the pirn (a pirn holds thread sort of like a bobbin, except the thread unwinds off the end of a stationary rod, not off the side of a rotating cylinder) or replace warp ends that have knots in them, or deal with other interruptions.

Wednesday, April 18, 2007

Wood Series Threaded and Ready to Weave

Threading a complex pattern like the wood-grain series is a time-consuming process. It used to be even more time-consuming, and much more error-prone, before I learned about the "treadle your threading" method.

Patterns that are easy to thread include the ones that go from the first shaft to the last, over and over: 1,2,3,4,5,6,7,8,1,2,3,4,5,6,7,8, for example. Or the ones that have an easy-to-remember repeat: 1,2,3,4,5 then 2,3,4,5,6 then 3,4,5,6,7, or 1,2,1,2,1,2,1,2 followed by 3,4,3,4,3,4,3,4, etc. For those, all I have to do is grab the next logical group of heddles and thread them in order.

The pattern I'm threading now has no easy-to-remember series, so what I do is set the pattern up with a treadling that is identical to the threading, and then tell the dobby mechanism to raise one shaft at a time. Each shaft raised represents one thread of the threading, in order. That way, I can see which heddle to grab and thread. Then on to the next shaft, grab one heddle and thread it. Slow going, maybe, but accurate. Computers have a much better memory than I do, they don't get distracted or bored, they don't lose their place. Believe me, this method is much more reliable than I am in full manual mode!

So here's the infamous cross (see previous post), suspended on lease sticks behind the shafts. At this point, the loops that secure the crosses of each individual 1-inch section have been removed, because the lease sticks are keeping the cross in place. (For you nonweavers, the cross insures that the threads stay in order while you thread; having carefully created the warp with the threads in a certain order, you want to keep it that way!)

I made a setup using clothesline cord and hooks that go into the holes at the ends of the lease sticks, which have hiking-boot laces tying them together through those same holes at both ends. All safe and secure while I thread the heddles and sley the reed.

Once the threads are drawn forward through heddles and reed, I untie and remove the lease sticks. They get to take a holiday until the next warp goes on the loom. The lease-stick hangers just slide to the back of the crossbar, where they wait out of the way until they're needed again.

After threading and sleying, the next step is lashing the warp onto the cloth apron. The warp is divided into bouts, each anywhere from 1/3 to 1/2 inch in width. I tie an overhand knot at the very end of each bout, and run a slippery cord through the middle of the bout, then around the apron rod, as shown in the pictures below.

The lashing cord may be easier to see in this shot taken from the front, looking back toward the reed (the metal piece with very skinny vertical slots - you'll probably have to click the image to display the larger version before you can see the slots).

Once the bouts are all lashed on, it's easy to manipulate the slippery lashing cord until all the bouts are the same tension. A little tug on each loop from left to right, then back again, and the tension equalizes.

This is as far as I'm going to get for now, because I'm off to Asilomar for the weekend, to attend CNCH, the annual Conference of Northern California Handweavers. This year the format of the conference is workshop retreat. I'm taking a 2.5-day workshop with famed artist, weaver, and teacher Alice Schlein on using Photoshop as a design tool for jaquard and dobby looms. Can't wait!

One of the nice things about this workshop, besides the great teacher and exciting topic, is that I only have to bring along a laptop equipped with Photoshop: no loom, no warping board, no shuttles, no yarn, no spinning wheel, no fiber at all. It'll be digital weaving at it's best.

Sunday, April 15, 2007

The Cross: To Tie or Not to Tie

There was a discussion on WeaveTech a while back about what to do with the cross when making a sectional warp. Some say you have to tie the cross; some say not to bother; and those who do tie the cross have various different methods of tying it and transferring the cross to the lease sticks or strings.

I'm in the Tie the Cross camp. I often work with fairly fine thread, and sometimes have 60 to 70 or more threads in a 1-inch bout. If it's going to be an interleaved threading, where color order really matters, the masking tape thing (or no cross at all) really makes me nervous. So I tie the cross.

I promised to post a couple of pictures of my method. The key, for me, is to use a piece of contrasting waste yarn long enough to form at least an inch of loop on either side of the bout. Here's an example:

Then I run my forefinger through the loops on either side of the bout, first back-to-front, then front-to-back. I tug gently to one side, and at the same time use my right hand to tug the loose end of the bout to the other side. The bout separates into a nice tidy figure eight that is easy to slip over the ends of the lease sticks.

With a sticky yarn, it may take a little more persuasion to separate this nicely, but never more than a few seconds. Getting the whole warp's worth of crosses onto the lease sticks and suspended behind the shafts is a matter of maybe a minute, tops. Of course, I weave scarves, so it's only a small number of bouts :)

Oh, and another thing: when winding the warp, whether sectionally or on a warping mill, I put the cross about a yard from the end of the warp. I hate to move the cross before threading - with fine or fragile or sticky yarns it's too easy to break or fray the yarn, so I wind the warp with the cross where I want it to be for threading.

That means my warping wheel isn't set up with the cross-maker where AVL instructs. And on my warping mill (I use a Harrisville vertical mill with an approximately 2-yard circumference) I use a third "arm" with pegs on it and place it half-way around the mill from the threading end of the warp. I figure that with a yard of slack, I have enough room to thread 24 shafts and have the tag ends hang over the front far enough that I don't worry about them sliding back out of the heddles while I thread the rest.

YMMV, naturally. I'm also a proponent of the "there's no one right way, just the way that works for you" school of thought.

Thursday, April 12, 2007

Polishing Wood (Designs, That Is)

I think I've finally got a weave draft that will give me the wood-grain texture I want. With a given threading, I can vary the design with a different tie-up and treadling for each scarf in a 5-piece run. The warp and weft yarns are hand-dyed, using dyes derived from wood. See Playing with Sawdust, below, for shots of the yarns and information about wood dyes.

Here are screen captures of the first three designs in the series. My weaving software (WeaveIt Pro) does a very good job of rendering the designs so I can visualize the woven cloth.

I wanted a design that would evoke the surface of a piece of wood, whether the grain of a slab of oak or curly maple, or the saw marks on a rough-sawn piece of timber.

The threading for this series is an interleaved nonparallel threading. Two different design lines are interleaved thread by thread. Each design line is threaded in a different color, one tan, one darker brown. By changing the treadling and the weft color for each piece in the series, I end up with 5 scarves that are each one-of-a-kind, even though they share the same warp yarns and threading.

Two more different treadlings, and I'm ready to go. In the meantime, I'll get the warp yarns beamed and threaded.

And Now for Something Completely Different

While I mull over the designs for the wood series (which is up next), I've been weaving a totally different style of scarf. The warp came off the loom a couple of days ago, and I've been working on the finishing since then. Finishing can be as simple as laundering and pressing, or in the case of cloth like this, there are some other steps that guarantee that industry would never be interested in this design, because most of the steps are completely hand-done.

For these scarves, I'm working with two yarns that will shrink and one that won't. The shrinky yarn is two shades of teal Zephyr (wool/silk blend from Jaggerspun, which I found on eBay at a very good price) and the nonshrinky one is a mohair/wool blend from New Zealand, made by Touch Yarns. I picked up a 2-kilo cone of the Touch yarn when we visited NZ in 2001. When it's gone, it'll be time for another trip to the Antipodes!

The design is a block weave that forms layers - one for each color in the cloth. This is a true 6-selvedge cloth. Here are a couple of pictures. You'll notice that the front and back can be very different with this weave structure.

I love the organic shapes formed by the white mohair/wool yarn! As the two teal yarns shrink, the white yarn has to bend and twist to get out of the way.

I do the shrinking in the washing machine, using as many cycles as it takes to get the texture I want. After spinning out the excess water, I take the damp cloth to the ironing board, cover it with a pressing cloth, and basically iron it dry. The pressing cloth prevents the corners of the iron from catching on the floats, but it also means I have no control over what's going on under there - the bends and twists do whatever they want.

Monday, April 02, 2007

Playing with Sawdust

I spent a few days recently playing with sawdust and wood chips gleaned from my husband's woodworking shop. Every time he works with a wood that has an interesting deep color, I scoop up as much as I can and squirrel it away in a bag labeled with the name of the wood. Wood makes great dye! To see if a particular variety has dye potential, just put some sawdust or chips into a canning jar, add water to cover (or even better, denatured alcohol - the cheap stuff found at Home Depot in 2-gallon jerrycans). Wait a while - minutes to weeks - and see what color the liquid turns.

I have in mind a run of scarves made mostly of wood-based yarn (tencel) dyed entirely with wood-based dye, and woven in a design that evokes wood grain. I've got one threading that gives the effect of rough-sawn timber, and am working on another that'll be more like the oak face of the built-in cupboards in the house. These will be interleaved threadings, with a dark color and a light color alternating thread by thread.

First, I mordanted the warp yarns using Michele Wipplinger's method for cellulose, which consists of a scour bath, a mordant bath (aluminum acetate), and a tannin bath (I used myrobalan, a wood-derived tannin). For the skeins that I wanted dark colors on, I also put them through an iron bath at 1% WOF.

Because I planned to dye with wood, which presumably all has some tannin in it, I wasn't sure if the tannin bath was really necessary. However, because I don't know how much tannin a given wood has, it seemed as if it would be best to ensure that there was at least a known amount in there.

Here are the warp yarns. The darker skein is 100% tencel in 30/2 weight, dyed with walnut hulls harvested last fall and fermented in a bucket of water since then. The lighter skein is a 70%/30% tencel/silk blend, also 30/2, dyed with madrone bark.

While the warp skeins were in their dyepots, I mordanted the weft skeins, one for each scarf in the run. Normally when weaving scarves, I use a weft thread that's finer than the warp for maximum drape. But because there isn't a tencel thread finer than 30/2 available to the handweaver, I'm using a 60/2 silk. The mordant procedure for silk is simpler - just a scour bath and a mordant bath of potassium aluminum sulfate.

Here are the weft skeins:

From left, they are:

Logwood grey (Earthues extract)
Bloodwood (chips soaked in alcohol)
Eucalyptus (dried leaves broken into pieces, soaked in water overnight)
Koa wood (Hawaiian tree, chips soaked in alcohol)
Mulberry wood (chips soaked in alcohol) plus Quebracho Red (Earthues extract)

Don't ask what kind of Eucalyptus it was. I harvested the leaves a couple of years ago when a neighbor gave his hedge a crewcut. They've been drying in a box in the garage since then. Here's a picture of a couple of the dried leaves. They range from 1.5 to 4 inches in length and are a silvery blue/green. There are probably more different varieties of Eucalyptus than any other type of tree. This one is a mystery. All I can say is, the leaves dye yellow.

The skein on the right in the photo above started out as plain mulberry dye, but as you can see from this picture taken while it was in the dyepot, it was fairly close to the eucalyptus in hue, and I wanted more variation in the weft colors.

So I looked in my dye cupboard for another wood-based dye that would shift the color a bit. I had some small amounts of the various Quebracho extracts from a warp-painting class with Michele, so I added a gram or so of Quebracho Red to the bath, and got an apricot color I liked better than the yellow.

The Koa skein, second from right in the picture of weft skeins, really surprised me. The chips were dark red, as was the liquid they soaked in, so I expected a reddish color on the skein, not the deep bronzy gold I got. And there's a ton of color in just a small volume of chips! I had filled a quart jar about 2/3 full of chips and covered with alcohol. The jar sat in the garage for about a week. When I went to use it, I just poured the contents of the jar into a dyepot, added a quart or so of water, simmered the whole mess for a few minutes, strained it out into a clean dyepot, and added the yarn. The color took almost immediately, to very deep value, but to make sure it would really be color-fast, I left the dyepot at under 140F for several hours.

Carol Lee of the Sheep Shed Studio in Wyoming has done a lot of wood chip dyeing, and teaches a class on the subject. On Carol's advice, I kept all the dyebaths at a low temperature (around 140F) to prevent the colors from turning brown with excess heat. All, that is, except the walnut, which I boiled to kill off the various forms of life in the bucket and reduce the smell somewhat. I also strained it twice to get the sludge out of it. Walnut is a dye you don't want to do in the house. It's really stinky, especially when it's been fermenting for months!

I had hoped for a deeper brown from the walnut, as I've gotten in the past on protein fibers, but the tencel just wouldn't get any darker, even after 24 hours in the dyepot. I was glad I had done the iron bath, or it would have been an awfully light brown!

Both of the warp dyebaths were cooked on a propane camp stove out of doors. The weft skeins I cooked in the kitchen, although DH complained that the alcohol made the house smell like a hospital. Fortunately, the weather was pleasant so I could open windows to air the place out. I am really looking forward to having a proper dye kitchen, so I don't have to cope with a propane stove outside in a breeze, or worry about getting my indoor kitchen spattered with dye or smelly with witches' brew concoctions!

All in all, it was a very successful dye project. Now, if only I could get the weaving design to do what I want... In the meantime, another warp goes on the loom and I'll keep working on the wood design in my head while weaving something completely different.