Undulating Twills

Marcy Petrini


On last week blog I showed a Christmas fabric with an undulating twill. The question came up: what is an undulating twill?

I like to think of an undulating twill as the result of stretching any twill. And there are many different ways to accomplish this stretching. Let’s take for example a straight twill: 1, 2, 3, 4, repeat. We could stretch it regularly:

This second, doubled, repeat changes the slope of the twill. We can also stretch the straight will irregularly:

This irregular repeat causes the undulating slope to be more pronounced.

My favorite way to undulating a twill is to do it in steps; I used this method for the Christmas fabric woven with a pointed undulating twill, shown here with its drawdown. The treadling is also undulating, but it is possible to use a number of treadlings, including straight and pointed twill.

Sett must be considered carefully. For example, look at the point where we treadle 3 & 4: the float is over 6 threads. At a sett of 12 ends per inch, the float would be ½”, likely too long for most useful fabrics. At a sett of 48, the float would be only ”. In the past I have used a different sett for different parts of the fabric, but that tends to diminish the undulation, defeating the purpose of the structure.


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Christmas and Complimentary Colors

Marcy Petrini


Since the day after Thanksgiving, our neighborhood has started to twinkle with Christmas lights and decorations. I love lights of any kind, but my favorite Christmas embellishments are textiles. I made several over time, and every time I weave with red and green I have to remember that they are complimentary colors: some kind of “trick” has to be used so they don’t dull each other (sometimes you read that they grey out, but to my eyes is more brown than grey).

If you look at printed textiles for Christmas using true red and green – or any other true complimentary color pair – you notice that the colors don’t become muddied. That’s because in printing, there are relatively large areas of each color. The muddying of the complimentary colors occurs when there is mixing, as in warp and weft interactions. To avoid dull combinations, I like to use one or more of three techniques that I have found work well: 1) change the intensity or saturation of one of the complimentary colors; 2) use a tertiary color as a substitute for one of primaries; 3) add a third color.

For the first technique, we can use a tone (adding black) or a shade (adding grey) of one of the two complimentary colors, for example, a dark green with true red, or a dark red with true green. A tint can be used just as effectively, that is, a lighter color obtained by adding white, for example pink instead of red with true green. Better yet, use a mixture of all of them. The piece below, a plaited twill for a Christmas tree skirt, uses a variety of greens for the warp.


This fabric also uses the second method, substituting the tertiary of one of the two complimentary colors; for red, the tertiary is red-orange, obtained by mixing the primary red with the secondary orange (which in turn is obtained by mixing two primaries: red and yellow give us orange). The weft of the tree skirt is red-orange.

The fabric below shows the third method. To the red and green I added silver, which has the benefit of having some sparkle. This undulating twill was used for a Christmas wreath sash, using a red warp, and a weft of green with a silver thread.


Now take the complimentary blue and orange and see what you can do to make them sparkle!


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Colors in Nature

Marcy Petrini


I love color and nothing inspires me more than nature, with her subtle differences in shades, juxtaposition of hues, and tint contrasts that make the eye jump from one color to the other. Here in the South, the brilliant spring shades of flowers lead to a myriad of summer greens, followed by greens dotted with a bit of fall colors, leading to more muted browns in the winter. But we don’t get the brilliant fall colors that I love most, so I like to get away in autumn to the woods north of Mississippi. Earlier in the month we did a bit of driving and walking in the Blue Ridge Parkway in Virginia. The local folks told us that the peak of the fall colors had passed; no matter, those glorious colors were all around us.

So, I came home and planned my next weaving project, inspired by the trip: sage green, rust, gold and brown in silks and cottons, with a pointed undulating twill, also inspired by the trip: the wind rustling through the trees moved the leaves and branches in waves. The warp in on the loom…..

Meanwhile, I am reminded that this was not the first time I came home from a fall trip and just had to weave those colors; a couple of years ago we went to the hills of Arkansas and I came home to paint those browns, greens and a bit of orange with oil-based crayons (Shiva Artist’s Paintstik®). There was some snow already on top of the mountains, so I left some of the 10/2 white cotton warp unpainted; then I wove a scarf with a light brown 5/2 silk using a broken twill, shown below:

Fabrics, painting and photography can reflect nature’s colors, but nothing comes close to what the eye can actually detect. Still, looking at the scarf, I can see those glorious mountains in my mind’s eyes

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Sleying and Reeds

Marcy Petrini


I wanted to sley my fall color warp (see Blog of 11/30/15) at a sett of 20 ends per inch, but I don’t have a 20-dent reed. I do have a 10-dent reed, and conventional wisdom would have me use it and sley 2 warp ends per dent (epi).

I often dent multiple warp ends; I think that, when threads are sett more closely, sleying one per dent may cause the threads to rub the metal slats of the reed and be weakened by it. So, I sley a 36 epi warp double in an 18-dent reed; a 48 epi warp is sleyed 4 per dent in a 12 dent reed, and so forth. Of course, not all combinations have to have the same number of threads per dent.

Somehow, though, this 20 epi warp seemed “too lose” doubled in a 10-dent reed. I think that the multiples work better when the threads are a bit smaller. The 36 epi warp doubled in an 18-dent reed mentioned above works just fine, but a 10 epi warp doubled in a 5-dent reed can bunch up and not spread out evenly. So, for this 20 epi warp I wanted another sleying. I have reeds with 12, 15 and 18 dents for that loom. What would my denting look like? The principle is to make the sleying as even as possible across an inch; but we also must remember that the last dent of an inch is followed by a dent for the following inch, and the evenness must continue.

For these reasons, I like to figure out my denting for two inches, here superimposed because of space. Following is what my sleying would look like in the 12, 15 and 18 dent reeds for the 20 epi warp; the first row in each table, with the red numbers, represents the dents in the reed; the second row is the denting of the 1st inch (beige background) and the third row is the denting of the 2nd inch (in light blue).

Notice the transition between the 1st and 2nd inch: for example, in the 12-dent reed, the 2, 2, 1 denting at the end of the 1st inch is followed by the 2, 2, 1 denting at the beginning of the 2nd inch. The same even progression is true for the other reeds. Ultimately I decided to use the 15 dent reed; I was afraid that doubling every 9th thread in the 18-dent reed may show up as vertical lines; the 15-dent reed is more regularly spaced, as is the 12-dent, but the warp is more spread out in the 15th. The weaving has begun…

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Weaving Errors: Treadling

Marcy Petrini


The registration booklet for HGA’s Convergence 2016 is off to the printer, I am told, so this seems a good time to start a blog, as I organize my thoughts about the seminars I am scheduled to teach. One that is totally new from all of the previous Convergences where I have taught, is about weaving errors: what strategies can we use to minimize them? What can we do to fix them after they occur? It is so discouraging to see this after the cloth is off the loom: in the fabric below woven with a black weft, do you see the missing shot in the second diamond from the top?

The pattern should look like the fabric below, woven with a blue weft:

These kind of errors are hard to fix off the loom. An additional weft can be added, following the path of the missing one, but the extra weft will make the fabric denser in that spot; sometimes this is not very noticeable, or at least less noticeable than the wrong motif, other times is just as obvious. It is best to use a strategy that will help us avoid those mistakes. I like to visually match my cloth to the drawdown step by step. This and other strategies will be part of the discussion at Convergence.

Other errors can be successfully corrected off the loom. The fall issue of Shuttle Spindle & Dyepot, besides the Convergence registration booklet, will also have my “Right from the Start” article on fixing some of these errors by mending. Stay tuned….

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