How to Adapt the Warp Sett for Your Fabric

Marcy Petrini

July 2019

At the Beginning….

People generally learn to weave with plain weave. To start the project we need to explain the sett. We wrap the yarn around a ruler, count the threads in one inch, and explain that we call the measurement the yarn size or grist or diameter (d) in wraps per inch (wpi) and that we will use half that number for our sett in ends per inch (epi) because our finished product will have half warp and half weft; then we hand the rulers to the students and let them try, admonishing not to overlap the threads and not to leave empty space in between them, as show below.



As the old saying does, “you gotta start somewhere”. We may mention that we will explain for future projects how the sett varies, but first impressions are powerful.

So, there was the time we used a 5/2 cotton sett at 16 epi – and 16 epi became “the sett” – for everything (“you told me to sett it at 16”); or the time that we used 3/2 cotton sett at 12 epi in a 12 dent reed and the conclusion was that the reed determines the sett, and not the other way around.

Those are rare instances, no doubt, but I do think that beginning weavers sometimes are looking for a magic number. “What’s the sett for 10/2 cotton?” asks the e-mail. Ah, if only sett were that simple! But with a bit of thought and understanding, it doesn’t have to be that hard, especially since we have some leeway.


The Determinant of Sett

Let’s look at all the assumptions that the instructors make for that first project:


Structure: plain weave

The sett is diameter (d) divided by two – but only if the following two determinants are true

Weft: same size of the warp

The sett has to be adjusted if the weft is larger or smaller than the warp

Balanced fabric

50% warp and 50% weft on both sides of the fabric; usually, but not necessarily, true with plain weave if the weft grist = warp grist

Yarn and Fiber

Not too slick; we usually don’t start weaving with slick silk

Final use

A tablemat should be sturdy not flimsy, a scarf should be flowing not stiff. A rug can be totally warp-faced or weft-faced

The Weaver!

In starting out, we assume that the weaver will be “average”, but as time goes on, we learn what our personal preferences are. Experience! Experience! Experience!


Let’s look at these individually and see if we can use some principles.



Plain weave has the shortest floats, each weft goes over and under each warp thread, each warp thread over and under each weft thread.

But when we have longer floats the fabric can be unstable, too much wiggle room as shown in the picture below, where the warp ends bunched together.



When we have floats, we adjust by setting the warp more closely.

How much more closely?

For twills, a rule of thumb is that balanced twills should be sett at least 20% closer than plain weave. For that 5/2 yarn that we sett at 16 epi for plain weave, we would use 20 epi for a twill.

Unit weaves form lacey blocks and plain weave. You may read that lacey weaves should be sett more openly, the same or closer than plain weave. All of those are true and the sett varies on the proportions of these. If there is a lot of plain weave, we may want to use a more open sett to accentuate the lacey areas; if there are a lot of lacey blocks, then the sett should be a bit closer because the floats can make the fabric unstable. A huck lace that has all lace and no plain weave (except the selvages) using 10/2 Tencel® usually sett at 24 epi for plain weave, I may sett it at 26 epi.

Supplementary weaves have a ground of tabby, but the supplementary weft is generally larger than the ground weft, which is traditionally the same as the warp. In this case, I open up the tabby sett a bit, to allow room for the supplementary weft. A 10/2 cotton, that may be sett at 24 epi for tabby, I sett at 18 epi for a tabby of a supplementary weave.

There is actually a formula for calculating the sett for different structures, but while I used to really like to use it, with time I found it unreliable for some unbalanced structures, and those that have different size floats with different picks, for example a birds’ eye twill.

Fortunately, we don’t have to do any calculations from the formula to find reasonable setts. While there are lots of sample setts on the web for the various commonly used yarns, there are differences in twist in yarns which effect the sett. The best place to find the sett for a specific yarn is to use the web site of the yarn vendor.

Manufacturers of yarns may provide either a range for setts or ranges for plain weave and twills. For example, for 10/2 cotton, the sett suggested may range from 18 to 36 epi. The 18 is for drapeable plain weave or a lacey structure with lots of plain weave, for example used in a scarf; the 36 is for unbalanced twills. About in the middle is a balanced twill, 24 epi.

Alternatively, the sett suggestions may say: plain weave: 18 - 24; twill 24 - 36; in this case, the 24 is suggested both for a sturdy plain weave, for example to be used in a placemat, or a balanced twill. The suggested setts for a given yarn usually take into consideration the fiber, so they are worth noting, even when wrapping the yarn to determine its grist.


Warp and Weft Size

Often, we use the same size weft as the warp, but sometimes the perfect yarn for the project is larger or smaller.

If the weft is larger than the warp, the sett must be more open to make room for the weft; if the weft is smaller than the warp, the sett must be closer to avoid the weft to pack in and make the cloth too stiff.

For example, for 10/2 cotton woven in plain weave for warp and weft, the average sett is 24 epi. For the runner below, woven with a larger ribbon, the warp was sett more openly at 18 epi.




The scarf below was woven with a multicolor 5/2 bamboo for warp and a purple 10/2 bamboo for weft in a twill. For a balanced twill, the sett of the 5/2 warp would have been 20 epi, but because the weft is smaller, a sett of 24 epi was used. This makes the fabric more stable but also allows the multicolor warp to be the focus of the scarf while still having good drape.




 Balanced and Unbalanced Fabrics

A balanced fabric is one where the same amount of warp and weft shows on each side; both plain weave and 2/2 twills can be balanced, if we use the same size warp and weft.

In an unbalanced fabric, the weft shows more on one side, the warp on the other as shown in the picture below of a  3/1 twill, front and back; 3/1 means that for every shot, 3 threads remain down while 1 thread is lifted.




How do we sett the warp for these fabrics? Closer than for a balanced twill. I already mentioned that when vendors give a range for twills, the upper value is for unbalanced fabrics. Let’s use the example of 5/2; we may sett it at 16 for plain weave, 18 for a balanced twill, and 22 epi for the 3/1 twill.


Yarn and Fiber

The general sett recommendations for 10/2 unmercerized cotton, 10/2 mercerized cotton and 10/2 Tencel® (which follows the cotton count) are the same. But there are differences. Look at the photo below:




There are 6 wraps for each of the three yarns, which are: 10/2 unmercerized cotton (blue), 10/2 Tencel® (rust) and 10/2 mercerized cotton (yellow), occupying the portion of an inch as labeled. Translated to epi, the setts would be 19, 20 and 23, respectively, with some differences, especially between the unmercerized and mercerized cotton; visually, I can see that the yellow yarn has a higher twist than the others. This is not surprising as I have found differences between mercerized cottons of the same count and Tencel® of the same count. In using the yarn, such differences may not matter, but I still think it is important to consult the yarn vendors for their sett recommendations.

Silk is the one fiber that benefits from a closer sett as it is very slippery. Luckily, all silk yarn vendors have helpful tables for their yarns.


Final Use

I wouldn’t use 3/2 cotton to make a scarf, the fabric wouldn’t drape as well as I’d like, but 3/2 makes great mats; for a scarf, I would use 10/2 cotton, which I wouldn’t use for a table mat, I think the sturdier 3/2 works better.

In between is 5/2; it could be used for a scarf and for a matt – but not with the same sett. For a scarf I may use an open 18 epi, for a matt a tighter 20 epi.

The ranges given to us by manufacturers are rather close, but we have a lot more leeway. To weave a tapestry or a weft-faced rug, we sett the yarn 5 or 8 epi, depending on the size of the weft, so we can cover the warp totally, on both sides of the fabric, as shown in the photo below, front and back.




At the other end of the spectrum, we can weave a rug with rep weave, warp-faced plain weave; we sett rep close to 4 times the yarn wraps per inch, to make sure that the top and bottom of the fabric are both solid warp, as show in the photo below, front and back.





Think carefully about the final use for a perfect project!


The Weaver!

As we weave, we find our preferences; some weavers like their warp tension high, some low; some like to beat hard, others softly.

Which combinations you prefer may impact your fabric; if you like to beat hard, you make great rugs – what if you want to weave a scarf? You can adjust the sett.

I know that I like to beat rather hard – not as hard as beating a rug, but certainly to weave lacey weaves, I have to fight my tendency. I also like to keep my warp pretty tight, which minimizes possible threads getting caught in the middle of the shed, especially with a sticky warp.

Rather than fighting my tendencies, I adjust the sett. By using a slightly larger ends per inch than recommended, my warp will provide some resistance to the beating; and since a tight warp also promotes heavy beating, the closer sett helps with this tendency as well.

Pay attention to what you like and learn over time to adjust accordingly.


Where Do I Go from Here?

You see why I couldn’t answer that email “What’s the sett for 10/2 cotton?” with a single number, but here is a plan to get started. And, no, I won’t use the dirty 6-letter word (sample), although sometimes that’s the best way to get the answer.

Let’s say you have chosen the yarn and the structure, and you know what you want to make.

  1. If you have to buy the yarn, use the high end of the sett for your calculations for the yarn purchase, so you won’t run out of yarn.
  2. If you have the yarn, or when the yarn arrives, do the following:
    1. Wrap the yarn around an inch, as described above, no overlap, no empty spaces, divide by half; this is your starting epi.
    2. Think about adjustments for the pattern, the weft size if different than the warp and what your finished product is going to be; adjust the starting epi accordingly; sometimes your adjustment may be a calculation (20% increase for twills), sometimes it’s “a little bit” higher or lower – 18 or 14 instead of 16, don’t use odd setts; if your calculations give you 21 epi, use 20 or 22, depending on what you are making.
    3. Compare the adjusted epi you have just calculated with the values recommended by the yarn vendor:
      1. If you agree, you are good to go! Go wind that warp!
      2. If you don’t agree, figure out why:
        1. Are you making a very sturdy piece that requires a higher sett than recommended?
        2. Are you using a slick yarn, like silk, so the vendor is recommending a closer sett than you had calculated?
        3. Make your final decision and proceed with warping.
      3. If when you start weaving you find that your sett is not quite right, you can re-sley, remembering that there can be two potential issues:
        1. The width won’t be the same; if you need to re-sley with a closer sett, the width will be less; more open, the width will be more.
        2. Depending on the adjustment, there could be a potential tension problem because the threads no longer will travel a straight line from the back of the loom to the front, they will either fan out or squeeze in, depending on the direction of the new sett.
        3. An alternative to re-sleying is to change weft size, which is a cleaner solution:
          1. If the sett is too open, use a larger weft.
          2. If the sett is too close, use a smaller weft.
        4. Once you are done, keep notes. This is the most important part for future use. Keep a spreadsheet if you are comfortable with them, or a table of some sort. List the following:
          1. Warp yarn used, be specific – not “cotton”, but 8/2 unmercerized cotton.
          2. Weft yarn used, say at least “same as warp”, if that’s the case.
          3. The structure.
          4. Final use of the piece.
          5. The sett in epi.
          6. Your impressions: note whether you are totally happy with this sett, or whether you are relatively happy but next time you may sett this yarn more closely or further apart. And, yes, do this even if the project turned out not to be to your liking. That may be the best lesson.
          7. Any other thing you may want to remember.
        5. When reading a published project, note the same information as above, even if you don’t plan on using it. Add it to your table or make a parallel table of use by other weavers. You can compare your setts with those of others and make conclusions about similarities and differences.

Soon you will have a table – your table – which will give you a feel for how you like to sett various yarns. Experience comes from paying attention to what we do right – and what we do not so right.

 Happy weaving!


Using Variegated Yarn for Weft

Marcy Petrini

June 2019

Some of the same principles that we discussed last month in using a variegated yarn for warp apply to using a variegated yarn for weft, if we want to make the pattern more visible: a bold pattern, not much contrast in the colors of the variegated yarn, but more contract between warp and weft colors; the distance at which we want the pattern visible is also important.

There are some differences, however: in the warp, the color repeats of the yarn are generally more spread out, because of the length. When used as a weft, how the colors of the variegated yarn are organized depends on the width of the piece, which is usually not the same as the length of the warp. So colors in the weft can stripe, pool or look more random, depending on the relationship of the color repeats with the width of the piece.

Also, think about how we wind our bobbins or shuttles: first of all, chances are that we won’t wind exactly the same yardage on each bobbin; but more important, we can start winding at the beginning of a ball or cone, say point A, and wind to point B, which is where out weaving begins; for the next winding, we will start at point B and end at point C, which is where the weaving begins, so the colors will no longer be in order; for the weft in the fabric we have: B to A, C to B, etc.

Of course, if we really wanted, we could carefully rewind balls and match to keep the colors in order, but that is a bit tedious.

Below is the pictures of two scarves both woven with a ribbed twill using two yarns, Reno Sunrise which is variegated and cinnamon which is solid. On the left, the warp is solid, the weft is variegated; on the right, the warp is variegated, the weft is solid. From a distance, the scarf with the variegated warp is more interesting. There is some cinnamon in the variegated yarn, which blends with the weft, resulting in the other colors being more prominent.


The close ups of the scarves are below, first the variegated weft, then the variegated warp. Close up the ribs are more visible with the variegated weft, while the twill line is more visible in the variegated warp. Which is better? Totally a matter of personal preference.




When using a variegated yarn for weft, I often want to showcase the colors, rather than the pattern. I use these possible combinations, often, but not always, in plain weave:

  1. solid warp, variegated weft;
  2. different solid warp colors, variegated weft;
  3. striped warp and variegated weft;
  4. both warp and weft variegated;
  5. both warp and weft variegated, but different yarns.

Below is a close up of a scarf with a gold silk warp and a variegated cotton weft, woven on my rigid heddle loom. I like the way the colors migrate across the width, almost like a watercolor painting.



The scarf below has three yarns for warp: rust, peach and purple, all solids 5/2 cotton; the weft is a variegated rayon weft with the same colors plus some green; It was woven in plain weave. I like the way the colors pool.


Three broad stripes in chestnut, cheddar and cranberry make up the warp of the scarf below. The weft is a variegated yarn called sugar maple with golds, greens, reds and browns. It was woven as a broken twill.



Note how the different colors of the weft disappear in the warp stripes, depending on its colors, shown in the close up below. This is a good strategy when wanting to showcase certain colors.



Compare the two scarves below, both woven in plain weave. The one on the left has three solid warp threads in blue, aqua blue and red purple with a variegated rayon weft of the same colors plus a bright green. The same rayon is used for warp and weft in the scarf on the right. The variegated weft results in irregular stripes on the left, and the interaction between warp and weft forms a crazy plaid on the right.



This scarf has a variegated Tencel warp in blues, greens and purples, and a variegated silk weft of blues; the variegated weft accentuates the blues of the variegated warp. The advancing twill causes a textured appearance from a distance.



What color interactions do you like for your variegated yarns?

 Happy weaving!


Deflected Double Weave

Marcy Petrini

April 2019

 In double weave, we weave two layers of cloth which can be joined on the loom to form a double cloth or a tube. In deflected double weave, the two layers are interlaced, causing the deflection; the technique can be woven for differential shrinking, by using a yarn for one layer that fulls more than the yarn in the other layer. Often more than 4 shafts are used, so the two layers are not restricted to plain weave. A few years ago, I wanted to weave a deflected double weave fabric, not to full it, but to understand how it works; to get started, I chose to adopt the pattern than Holly Brockman published in Fabrics that Go Bump (page 94). The bottom layer is plain weave on four shafts, interlacing and anchoring the floats of the top layer horizontally and vertically, forming motifs. Here is a close up of the fabric:




The ground warp and weft are 10/2 Tencel® from Just Our Yarns, from a past Convergence®; it is variegated in blues, greens, and yellows, called Great Lakes Sunrise. The overlayer is 20/2 silk from RedFish Dyeworks in blues. The draft is below; the drawdown doesn’t show the interlacing of the bottom layer, but the draft has the threading and treadling directions. The ground warp and weft are shown in green, the overlayer in blue.


Click here for the full-sized draft (a PDF will open a new window)


The ratio of top and bottom layers – here 4 / 6 – determines the number of threads in the float, so the sett is important; I used an 8-dent reed and I sleyed 2 per dent for the Tencel® and 4 treads in one dent for the silk. I liked the fabric and I thought that “one of those days” I will try it for differential shrinking. More recently, as I was thinking about puckering fabrics, I wondered: why not deflected double weave on 4 shafts? The ground fabric in the 8-shaft version I wove was plain weave on four shafts, which can be simplified to two shafts; the top layer could have floats anchored by plain weave, using the other two shafts. I am sure other people have had this idea, but it was easy enough to figure this out from scratch. Below is the draft of the fabric that I wove. The bottom layer was woven, as in the 8-shaft version, with 10/2 Tencel® (from Margaret Pittman, no longer available) variegated in reds; in the draft the warp is red, the weft is pink to show the intersection; the top layer is red Jaggerspun wool; in the draft, the warp is burgundy, the weft brown.




I used the same ratio as for the 8-shaft version, 6 threads for the ground, 4 for the top layer and I sett the warp the same way in an 8-dent reed. Below on the left is the fabric off the loom, on the right after it was washed in hot water and hung to dry. There was about 40% shrinkage, so the two fabrics in the pictures are the same dimensions.



The back of the fabric before washing (below on the left) is pretty flat, but it becomes bumpy after washing (on the right).



A summary of the 4-shaft deflected double weave is in the Pictionary, downloadable as a pdf.


  Happy weaving!


Will the Pattern Show If I Weave with Variegated Yarns?

Marcy Petrini

May 2019

This seemingly simple question was posed by one of our weaving students. Heather loves color and she loves pattern, but so far, she has not woven with variegated yarns – hence the question.

The answer is “it depends.” It depends on the pattern and it depends on the colors.

Below are two pieces woven with similar color yarns for warp and weft. The deflected double weave (first below) with a variegated warp of blues, greens and gold shows the pattern woven with a blue weft much more than the advancing twill (second below) also woven with a blue weft on a variegated warp also of blues, greens and gold.




The deflected double weave is a much bolder pattern and thus more visible.

Below are two sections of a scarf with a variegate warp; the shadow twill (not to be confused with shadow weave) is clearly visible in the picture below where there is good contrast between warp and weft.



But in the section below where there is low contrast between warp and weft, the twill just about disappears.




We can also ask: what do we mean by: “will the pattern show?” From what distance?

To me, a successful fabric should look interesting close-up and far away, especially if it will be viewed from different distances; but it is not likely that the same elements that provide interest from near will also do so from far.

The close-up of the fabric below is an extended pointed twill; the warp is variegated purples and greens and the weft a solid lighter purple. Because of the contrast in the purples, the diamonds of the pointed twill are visible when looked closely.



But from far away, the diamonds disappear, and we are left with changing colors that cause our eyes to move because they reflect the light differently depending on the direction of the twill.




We can use pattern to affect our colors – and the hand of our fabric. For example, twills give fabric drape and fluidity because of their staggered floats, so it may not matter if the pattern is visible. As we saw in the scarf above, the different colors of the twill can reflect the light in different directions, giving interest to the scarf from afar.

With so many choices, how do we proceed? Here are some guidelines, to get started.

To make a pattern more visible with a variegated yarn:

  1. Choose a variegated yarn that does not have colors with strong contrast in hue or intensity.
  2. Choose a bold weaving pattern.
  3. Use the variegated yarn as warp.
  4. Choose a solid color weft, contrasting to the warp in hue, intensity or both.
  5. Make the project slightly weft dominant; that is, sett the warp slightly more open that you would for that pattern and yarn, and make sure you don’t beat too much. Or use a weft that is slightly larger than the warp.

The pattern of the straight twill of the shawl below is visible because the red purple weft is darker than the variegated red and blue purples of the warp and it is lightly larger in grist.



What about variegated yarns for weft? We’ll discuss those next month.



 Happy weaving!


Weaving Ruffles

Marcy Petrini

March 2019

In the Spring 2019 issue of Shuttle Spindle & Dyepot (# 197), there is a wonderful article about Ann Richards and her collapse fabrics.  

I have long been intrigued by three-dimensional textiles, but I have never systematically pursued them. Here and there I have dabbled to make some simple ones, projects that may be suitable for my teaching. One technique I have tried is to make ruffles. 

A few Convergences® ago I found some stretchy yarn that I thought would be fun to weave. It is a 1% Lycra®, 99% cotton loop, close in size to 5/2 cotton, hand-dyed in wine and purple by Teresa Ruch and available in her booth.  

To weave it, I wanted to have stripes of the Lycra® to make a sample scarf with ruffles; to figure how what the rest of the scarf should be, I tried yarns in cotton, wool and silk of approximately the same size as the Lycra®. The silk ended up giving me the results I was looking for: drape and not too much fulling so that the Lycra® could contract. 

On my shelf I had a wine color 100% silk, Hana from ArtFibers which wrapped at 22 wpi. It is a bit smaller in grist than the Lycra®, but it had a wonderful hand and the colors went well together. I decided to use it and sett it at 15 epi, while the Lycra® would be sett at 12 epi. 

I divided the 6” width into: 1” silk, 1” Lycra®, 0.5” silk, 1” Lycra®, 0.5” silk, 1” Lycra®, 1” silk. 

To weave it, I used plain weave for the silk, threaded on shafts 1 and 2, and ribbing for the Lycra®, threaded on 3 and 4, as shown below. The weft was the same Hana silk, even though I used I different color in the drawdown, so I could see the structure. 




To avoid floats where I didn’t want them, the structure required an even number of threads, so I adjusted the width slightly; the 1” of silk was 14 treads, and the 0.5” was 8 threads, so the total was just a threads short (44 threads rather than 45 for the silk). 

The bouts of Lycra® were tension separately with weights since the loom I planned on using doesn’t have a second beam. 

In sleying, I didn’t want to bunch up the silk, so I chose a 15 dent reed, sleying the silk 1 per dent, and sleying the Lycra® 1, 1, 1, skip 1. 

Here is a photo of the finished scarf. For didactic reasons, I chose not to trim the considerably longer silk fringe. Of course, for a finished project, I would trim them all to the same length, but I would also leave longer fringe for the Lycra®. Perhaps beads at the end of the fringe could stretch the Lycra® so extra length may not be necessary. 




Not surprisingly, there was some take up and a lot of shrinkage. The Lycra® didn’t crimp much until it was washed. Length-wise the take up was approximately 10%, but the shrinkage was nearly 34%. I had planned about 30% take-up and 50% shrinkage, so the final length, almost 70” was plenty long. In the width, the take-up was 8% and the shrinkage 5%. I hope this inspires you to try some Lycra® in your weaving!  

  Happy weaving!
