The Liftplan

Not too long after I had gotten my brand new loom, I realized I was instantly drawn to complex 8-shaft patterns.

The first draft I bought (and used for my first multishaft project!) was an advancing twill design on all 8 shafts.

If anyone is not familiar with advancing twills, some have long or not easily identifiable repeats when you are threading your warp yarns (which was the case for my pattern). Its the same story for the treadling – like a complex knitting chart, you need to work very slowly and pay attention.

This immediately created a problem for me. My table loom has no treadles. Not only do I have no identifiable pattern, for each treadle I have to set the 8 levers exactly. The  headache that was going in my mind wondering how I I would keep my sanity while trying to make sure I made no mistakes made me wonder if this was the right loom. Should I have gotten a floor loom with treadles?

 I started brainstorming immediately to find ways to simplify this process. My first solution is the subject of this post. My even better refinement will be the subject of another one.
My first thought was – since I don’t have treadles – I don’t really see the point in referring to that part of a weaving draft. I devised a sort of Numbers template (a mac equivalent to Excel) where I could convert one row of a weaving draft into the sequence of levers I had to depress:
This is better to visualize then explain. Below is the draft that I posted in a previous post:
 
And this is what I converted it to in Numbers:
In the original draft, the first step is to lift the 8th treadle, and you can see in the tie-up that it lifts shafts 1,3,4 and 7 – so in the spreadsheet, I fill out those numbers. (The numbers go from right to left because that is the way the levers are arranged on my table loom).
Then I write out the rest of the treadles until it repeats.
And that’s pretty much it! I print out the chart, keep it by my loom and follow it, pressing the levers indicated in each row.
Being a new weaver, what I actually had created, unbeknownst to me, was a liftplan.
A weaving lift plan shows the same information as a typical weaving draft, with a couple of key differences. The tie up section is empty. The treadling section no longer represents the the treadles that have to be pressed – they now show which shafts have to be raised on each row.
After inputting the draft above into Fiberworks, I had it converted into a liftplan. Now the draft looks like the following:
This is exactly what I was doing in my spreadsheet diagram. (Leclerc Voyageur table loom users beware – shaft 1 on a liftplan is the leftmost shaft, but the lever that controls it on the loom is the rightmost! You may need to invert a lift plan.)
At the end of the day, since the software can easily convert a regular weaving draft to a lift plan, I could cut time in my preparation by simply using what the software was giving me, rather than spend time in a spreadheet creating my own charts:
I thought this would solve my table loom woes, but there was something even better…
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The Weaving Draft

It doesn’t take long when learning to weave until you encounter your first drafts, and it took me a while to figure out what they were and how they worked. I thought I’d write about how I learned to understand a weaving draft.

A draft can be considered to be the equivalent of a knitting pattern. Actually, not really. It’s more like a chart in a knitting pattern. Its not enough information for a weaver to start a particular project – details such as sett, yardage, material, finished project dimensions are all absent , but it provides information on how to set the loom up and work it to produce a cloth with a particular interlacement.

Drafts are usually divided into four quadrants. In the draft below of a 2/2 twill, I’ve labelled the quadrants A to D.

The Threading (A)

This section shows how the harnesses/shafts of a loom must be threaded. (Editor’s note: I used the term shafts and harnesses interchangeably without realizing and didn’t have time to fix it.) A harnesses job is to raise the threads that are assigned to it so that the weft yarn can pass underneath them. This section tells the weaver what threads each harness lifts and in what order.

The horizontal lines represent each individual harness. The bottom line is the harness closest to you if you’re sitting in front of the loom. You can also tell how many shafts your loom has to have to weave the draft by looking at how many rows are in this section.

Though there are many ways to thread the loom, two common ways to thread is straight threading and point threading.

In straight threading, a warp yarn goes through harness 1, the next yarn goes to harness 2 and so on. After you thread a heddle on the last harness, you go back to harness 1 and continue.

In point threading, you also thread harnesses 1 at a time. When you reach the end however, you change direction and thread the harnesses in the reverse order instead of starting back at harness 1. The original draft is shown below, with the only thing changed is the threading from straight to point threading. The diagonal stripes become horizontal zig zags.

The Tie Up (B)

Treadles (the floor pedals of a loom) are used to raise 1 or more shafts at the same time. The treadles on most loomes are usually fully configurable and can be set up to raise any combination of shafts you want it to. By doing so, the treadles provide the weaver a way to quickly raise combinations of shafts that form a pattern without having to think in terms of indiviaual harnesses (which is the case for my table loom). This section tells the weaver how to connect the treadles to the shafts.

Each column in quadrant B represents a treadle. Column 1 is for the first treadle and so on. If a row of that column is marked with a figure (usually an ‘O’ or its filled in), it means that the treadle needs to be connected to the shaft it is next to.

The Treadling (C)

This section simply tells you what order to press the pedals in to form a particular pattern the cloth. Like the threading, common treadlings are straight and point treadlings – they operate in the same way.

In the example of our 2/2 twill above, if we change the treadling from straight to point, we now get diamond patterns:

You can probably notice by now that by using a point pattern on the threading, treadling, or both, introduces a lines of horizontal and vertical symmetry into the cloth. You can also see in drafts such as this that the pattern in the cloth can be seen in the the tie-up quadrant of the draft.

A final note about our example, you’ll notice that in this draft, the threading and the treadling order is exactly the same. You’ll see the instruction “tromp as writ” come up from time to time, sometimes in drafts where the treadling is absent. This means to simply treadle in the same order as is threaded, I imagine its an old way of saying “treadle as written”.

The Drawdown (D)

This section gives you an idea what the finished cloth pattern will look like – it basically shows you the resulting interesction of the warp and weft yarns, usually with the implicit assumption that the warp is a black yarn and the weft is a white yarn.

Sometimes, more than one repeat is shown in either direction so you can see how one repeat connects with one another when they are laid side by side.

In the diagram below, you can see how you can figure out how to draw this section if you know what’s in the other three. I show how the second pick (weft row) is drawn in our 2/2 point twill draft:

  1. First you look at the tie up associated with the treadle that is being pressed and determine which shafts are being raised.
  2. Next you look across the shafts and every column that is filled with a number represents the threads that that are being lifted
  3. Finally, in the current pick that is being drawn, you darken each square that is directly below the squares being lifted.Continue the process for each pick and you’re done.
One last note before signing off – what you’re seeing in quadrant D is a drawdown, the  key word being down. When we weave however, the cloth is actually formed in the other direction (from bottom to top). For that reason, sometimes you’ll see drafts with quadrants A and B at the bottom, which will show how the actual cloth will look as it is woven on the loom. For fully symmetrical patterns, the direction doesn’t matter. But for other drafts, such as our simple 2/2 twill at the beginning of the post, this will mean that what looks like a twill that travels in the right direction in the draft will actually travel in the left direction when it is woven!

I randomly designed something! / Postal surprise

Before I acquired my table loom, I started studying / trying to figure out how to intentionally design drafts (as opposed to randomly filling things out and seeing what happens!).

Apart from trying to figure some stuff out, I found an excellent series of articles in some old Shuttle Spindle and & Dyepot magazines given to me by my friend Phil.

But before I could comprehend any of it, the software engineer in me led me straight to weaving software. The first one I got was actually a lead from my friend Aaron, who showed me an app for the ipad and iPhone called iWeaveIt back when I just had my rigid heddle. It is based on the WeaveIt weaving software package (which I can’t own since I don’t have any windows PCs)

It’s basic and cheap but it does excel at quickly doodling / visualizing drafts on the go.

I also have been evaluating Proweave and Fiberworks. They’re both great but I have a smaller tilt towards Fiberworks. And they both run on Macs. A look at what weaving software can do would actually make a great post in of itself.

I came up with this draft in Fiberworks, All I did was select a point twill threading (and treadled in the same fashion), and tried to draw some pattern in the bottom left quadrant of my tie-up. Fiberworks then flipped, rotated and inverted that small drawing based on my parameters to fill the rest of the tie-up … and voila!

 I’m sure it’s in a pattern book somewhere. I picked some colors for warp and weft that it might look good in, and from all the initial random doodlings that I did where I had no idea what I was doing, I like this one the most. I would love to try weaving it some day. If everything I said sounds like greek I might just explain drafts at some point too.

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After I wrote the first draft of this blog a surprise came in the mail from Webs. (ok not really much of a surprise):

  Lots of great inspiration in my new library addition, and some tencel, merino, and alpaca/silk weaving yarns for future projects.

Looking at the colors, I think forest green and black would also make a nice color combination for my draft above. I just might try to make a scarf out of it.