Wednesday, November 28, 2007

Advancing Twills - A Simple Definition

By Leigh

In my last post I tried to give a simple explanation of the four basic twill categories. As promised, I'll now see how well I can do with a simple explanation of what advancing twills are.

Advancing twills could be categorized as "broken twills," (twills in which some shafts are skipped in the threading). In advancing twills, a number of warp ends are chosen (for example five ends) and are threaded as a section. Each section omits (skips) at least one shaft between it, and the next. (1,2,3,4,5 then 2,3,4,5,6 then 3,4,5,6,7 etc.) The result is that the warp section appear to be advancing (on paper that is.)

I understand things better with pictures, so let me try to explain it with some. Since advancing twills evidently are most suited for more than four shafts, my drawdowns will be for eight shafts.

A drawdown is a pen and paper (or computer if one has weaving software) representation of a weaving. The drawdown below is for an 8-shaft straight twill (each shaft threaded in successive order, 1 through 8). The threading is shown across the top, using numbers to keep track of which shaft is indicated.

Simple 8-shaft twill draft.The box in the upper right hand corner shows the tie-up. It indicates how the treadles are to be tied to the shafts, so that each treadle lifts whatever shafts are tied to it. In this case, I'm using a pretty standard 8-shaft twill tie-up. The end result will be that my weft will travel under three warp ends, over three, then under one, and over one. (This is known as a 3/3/1/1 tie-up.)

The column going down the right hand side of the page is the treadling order. Starting at the top, I treadle one through eight. Since this is the same as the threading pattern, it is also known as "as drawn in" or "tromp as writ."

The colored-in blue boxes give an idea of how the cloth will look once woven.

This whole thing is called a drawdown because one starts at the top corner (nearest the tie-up) and colors in the squares drawing down from the top.

OK. If I leave the tie-up and treadling the same, but begin to advance the threading, this is what I get:

8-shaft twill draft with advancing threading.I've taken sections of five warp ends each, and advanced them by skipping (omitting) one shaft between each section. Pretty neat, huh?

So what happens if I change up the treadling?

8-shaft advancing twill draft treadled as drawn in.This one is treadled as drawn in. You can see that the treadling pattern is the same as the threading pattern.

What if I do a point-type treadling?

8-shaft advancing twill draft treadled straight & reverse.As you can see, it is treadled one through eight and then reversed.

Of course, I only have a regular size graph paper notebook, so I only get a part of what the weaving will actually look like, but it's enough to really get me excited about this! And that's when I start asking, "what if........"

What would happen if I tried an extended point treadling? What if I did the advancing treadling and reversed each section? How would a rosepath treadling look? What if I used a different number of threads in my warp sections? How would it look if I changed the number of shafts skipped? And what about starting with a point twill threading to advance? Or an extended point threading? Then too, what if I changed the tie-up? Then there are color combinations to try. And different yarns to experiment with. As you can see, the possibilities are endless!

There are some rules to all of this, though at this point I don't have an experiential understanding of what they are. However, Stacey has done an excellent job with the workshop lessons, so that all the information is very handy.

My next step is to choose a yarn and measure a warp. I plan to warp the loom for the advancing draft above, and put on plenty of length to experiment with the treadling.

Posted 28 November 2007 at http://leighsfiberjournal.blogspot.com

Related Posts:
Twills - The Basics
First Advancing Twill Samples
Advancing Twills - A Few More Samples
Continuing with Advancing Twill Samples
Advancing Twills - Second Verse

9 comments:

  1. It looks like you've made a good start with advancing twills, and you're drafts are lovely and neat.

    I found the main problem with designing advancing twills is avoiding floats that are too long, so as long as you have drawn out a full pattern repeat you'll know if there's a serious difficulty before you start weaving. The long floats are more likely to occur when you have an advancing pattern in treadling as well as the warp threading, and when the advance repeat is shorter. I got some to work with 4 end advance, very few with 3, but most seemed o.k. with 5 end. You can get around this a bit by mixing the repeat number... enough, I'll let you get on with trying out your design. Hope you enjoy the results! I'm these weaves are fun.

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  2. I believe you drafted all that by hand! Great explanation!

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  3. Love it! As someone who has only ever woven on a rigid heddle loom, I'd like to thank you for a wonderfully clear explanation. And a serious case of loom-lust, too.

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  4. That was a lot for me to digest so I think I'll just try the top one since it seems simple and I've never used all eight sheds. I wish I could squeeze in some weaving time - this month!

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  5. I'm with Laritza---you did all that BY HAND?!?!?! And it looks so neat and professional.

    And I'm with Alison as well. You do a really great job of explaining things.

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  6. Leigh, thank you for these great tutorials on Twills! I have never had a chance to weave on "real" loom (triloom and rigid heddle are the extent of my experience)...but you make it sound so simple, I'd love to give it a try someday!

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  7. I haven't drawn a draft by hand since I got a computer. I am so impressed with your draw downs and explainations!!!!!!!!!!!!!!

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  8. Thanks for the explanation on advancing twills. I always enjoy reading and learning from your very informative blog.

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  9. Leigh - you need to give some serious consideration to teaching our crafts - this explanation of drawdowns is the most clear and concise I've ever seen. Congrats, and many, many thanks!
    Marty Mc of
    UKWSD

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