Monday, November 26, 2007

Twills - The Basics

By Leigh

Even if you aren't a weaver, you are familiar with twills. Blue jeans are made from twill fabric. You've probably heard of Herringbone Tweed, which is a twill fabric. My zig zag afghans are all twill weaves. After plain weave, it is probably the most common weave structure there is, and is usually the second structure new weavers learn.

The Online Guild is finishing up it's Advancing Twills workshop this month. I've had a lot of other goings on, but have been able to read through the workshop notes and start on some advancing twill drafts.

I have found that even though I have woven quite a few samplers and projects in twill, I am still usually unable to readily conjure up an image when terms like "extended point" or "rosepath" are tossed about, let alone "advancing twills". I think that this is because usually, I just follow a draft. When I'm done, I love the results, but can't say that I really understand it. I think this has been especially true of twills for me, because there are so many variations and ways to change them.

So before I got on with the advancing twills, I reckoned it would be good to go back and study the basics first. I find that when I attempt to explain something to someone else (in this case, you all!), it forces me to go beyond a superficial or passing grasp of the subject. In order to put it into my own words, I have to begin to understand the concept behind the terms. I'm hoping that this post will help me do that.

Close-up of sampler with straight twill & plain weave.
Twills are easily recognizable because they contain diagonals. Looking closely, the diagonals are like stair steps, with every step having at least one warp thread in common with its neighbours.

The sample on the left is a simple, straight, 2/2 twill. This means that the weft thread travels over two warp threads, then under two.

There are four basic categories of twills: straight, point, extended point, and broken. I'm going to focus on the threading patterns for each of these.

Straight Twills

Straight twill threading draft.







The threading moves in one direction because the shafts are threaded successively; 1 through 4, or 1 through 8, etc. It can go to the left, or the right, as long as it is consistent.

Point Twills

Point twill threading draft.






These reverse directions, ending on the same shaft they start on. It isn't limited to the number of shafts one has, and can extend beyond them like this,

Another point twill threading draft.








as long as the starting and reverse points always occur on the same shafts.

Rosepath

Rosepath threading draft.







is an point twill which is extended one thread more than the number of shafts available. I've included this one because I hear it referred to often, but have never been able to remember the draft when I hear it mentioned.

Extended Point Twills

Extended point twill threading draft.






combine sections of straight twill with point twill. Unlike point twills, in which the direction changes only once before returning to the starting point, extended point twills can change direction more than once.

Broken Twills

Broken twill threading draft.






have a "break" in the threading. In other words, some shafts are omitted. Rather than having a successive threading order, their threading order has skips in it.

There are other types of twill, but these are the basic ones. If I can just get them to stick in my head I'll be happy. Variations on any of these are endless. One can vary the threading, the treadling, the combination of shafts lifted (the tie-up), the type and size of yarns, sett, or the colors used. The number of warp threads the weft goes over and under can be varied. The warp can dominate the pattern, or the weft can.

So there you have it. Oddly, no one book of mine had a straightforward, complete definition for them all(!) Not sure why; perhaps each author simply puts down the most important feature to them. At any rate, here are the sources I used:

Advancing Twill OLG Workshop notes, by Stacey Harvey-Brown, The Loom Room, Staffordshire, UK, 2007

The Complete Book of Drafting for Handweavers by Madelyn van der Hoogt, Unicorn Books and Crafts, Inc., Petluma, CA, 1993

Eight Shafts A Place to Begin by Wanda Jean Shelp and Carolyn Wostenberg, self-published by Wanda J. Shelp, Worland, WY, 1991

The Weaving Book by Helene Bress, Charles Scribner's Sons, New York, 1981

Next I'll try to explain what an advancing twill is. Click here to go on to that.


Related Posts:
Advancing Twills - A Simple Definition
Mystery of the Zig Zag Twills - Lining up color stripes with twill threading
Waffle Weave - Another idea for twill threadings

9 comments:

Susan B. said...

I think this is very clear! And very relevant to what I am weaving right now! I need to get my head around what is actually happening so I can pick up the pattern again if I lose it. This is a great beginning to that. (I may bookmark this one!)

bspinner said...

Your explanation of twills is right on. It's much easier to read your explanation on twills then by "perfessional" weavers and authors. I think by the time they become authors they've forgotten how to write instructions down in a plain and simple matter.
A couple of friends have woven wall hangings of twill samplers. I've always told myself I would do that some day. Just haven't figured out when.

Sayward said...

That explanation was spot on. I always use the 'jeans' example too when I'm trying to explain twill!

Peg in South Carolina said...

I like the way you set up your images. I'm talking computer graphics here, not weaving! I'm indifferent to boxes around photos, but I do like them around the threading diagrams. And I like how you set up the text with the sample photo. You've given me an idea or two!

Anonymous said...

Thanks for your very clear explanations Leigh. I have had fun experimenting with twills but have not really sat down to analyze them. I just like the results!

Sharon said...

Wow - thanks! You leave me speechless and that's pretty hard to do. I'm so ready to weave and have no time to do it, especially in the next weeks. I read your blog and I get excited and then I get disappointed. I've finished spinning for my next weaving project, and unless we get some snow days, I'm going to be living in the weaving world vicariously through you. Waaahhhh~

Laritza said...

Faux Fair Isle! That is a good one!

Anonymous said...

How ever do you set up the heddles for a twill... I have been trying to figure it out for days and it's driving me mad. I have set up the warp twice and neither of them were for a twill.

Leigh said...

Hi Anonymous, Correct me if I'm wrong, but I assume you mean tying up the shafts to the treadles? If you thread the heddles 1st shaft, 2nd shaft, 3rd shaft, 4th shaft, and repeat, (on a 4 shaft loom) then tie:
shafts 1 & 2 to the 1st treadle,
shafts 2 & 3 to the 2nd treadle,
shafts 3 & 4 to the 3rd treadle,
shafts 1 & 4 to the 4th treadle.

Then treadle 1, 2, 3, 4 and you should see the twill pattern. You can reverse the treadling too - 1, 2, 3, 4, 3, 2, 1, etc. to get a twill zig zag effect.

Most weavers also tie the last two treadles for a plain weave:
Shafts 1 & 3 to treadle 5
Shafts 2 & 4 to treadle 6.

Does this answer your question? If not, let me know.

A good book to get is Deborah Chandlers Learning to Weave. It's an excellent resource that I still use.