Profile Drafts

Marcy Petrini

July, 2021

 

This month challenge for our on-line study group is to design various unit weaves based on one profile draft.

Profile drafts are a shorthand to list the threading order of blocks. Given the specific threading of each block, the profile draft can then be expanded to the threading draft for the particular sequence.

For example, we have the profile draft below and we want to weave it as a single, two-ties, unpaired structure with a 1:1 ratio, also called summer and winter:

 

B	B
		A

 

This can also be expressed as:

A, B, B.

 

We know that the design has one block of A and two blocks of B. The profile draft would expand to the drawdown below:

 

 

I choose to treadle it as single, but that is not specified by the profile draft. However, we generally treadle the number of repeats of the blocks, one repeat for block A, two for block B (note the drawdown is sinking shed).

In general, a block can be treadled using its pattern shafts with each tie down thread. In this example, for block A we have 1 & 3 vs. 2 & 3 (with tabbies in between).

In weaving, of course, we repeat that sequence throughout the fabric, and we would obtain the following cloth:

  

 

Given that unit weaves have fixed blocks which can be repeated, and organized in a variety of ways, profile drafts are ideal for designing with this group of weaves. Blocks can be combined in the treadling, adding more to our design possibilities.

I have seen profile drafts used for other weaves, but they can be unclear, as easily illustrated using overshot.

Some people define block A of overshot as:

                                                            1, 2

Traditionally, as defined by Mary Black, the block A is:

                                                            1, 2, 1, 2

But the threading could be continued, being aware that the supplementary weft float will span the width of the block.

When we come to the A, B, B profile draft, how would we translate it to overshot?

                                                1, 2, 3, 4, 3, 4

Or:

                                                1, 2, 1, 2, 3, 4, 3, 4, 3, 4, 3, 4

There is ambiguity.

But we can use the same profile draft, A, B, B, for other unit weaves easily.

For example, we can use the double, two-ties, unpaired unit weave, with a 1:1 ratio.

From its classification, we can deduce the threading; we also know that the rendition of the structure will require 6 shafts: 2 ties, plus 2 (“double”) pattern shafts per block and we have two blocks, A and B.

Here is the expanded drawdown, treadling the two blocks in the classical way.

 

 

 

 Here is a challenge for you:

Assume you have 8 shafts available on your loom. If you don’t, you can still do the challenge because, if you understand a structure, you can design it with any number of shafts. If you have more, feel free to expand to more unit weaves.

Use unit weaves only. The number and arrangement of pattern shafts can be changed, and the number and arrangement of tie-down shafts can be changed, giving lots of options.

Use this profile draft:

 

			D	D
		C			C
B	B					B	B
								A

 

 How many different unit weaves have you discovered?

 

Happy Weaving!

Marcy

 

 

A Wonder Year of Weaving - An Assessment with Answers

Marcy Petrini

June, 2021

Last month for the May 2021 blog, I posed a set of 8 questions that the study group I am leading used as a review of the first 4 months.

For these months, here are the answers. If you haven’t looked at the questions yet, you can do that now (in the May Blog, click here) and then check how well you know Emery’s “simple weave.”

Here are the 8 questions, 2 per month, that I posed to the group. The instructions are to try to answer as many as possible from knowledge, but then to look up what they don’t know, have forgotten or need to check.

How well did you answer these questions?
 

1.  What is the difference between tabby and plain weave?

Plain weave is a fabric with the most interlacements which range from warp to weft faced.

 

 

Tabby is a perfectly balanced plain weave, 50% warp, 50% weft on both sides of the fabric, wpi = ppi. For a given yarn, the wpi is not fixed; we would sett the tabby ground for an overshot more openly than for a plain weave tabby cloth.

 

 

2.  How would you adjust the warp sett to weave a weft-faced fabric?

To cover the warp and produce a weft-faced fabric, we open the sett to as low as 5 epi, depending on the size of the weft.

 

 

 

3.  What is the best option for nice selvages on a straight twill woven as a straight draw?

 

Enter the shuttle on the side of the warp where the first thread is down. Every warp thread on both sides will be caught. If you forget this and you don’t catch the warp ends on both sides, reverse the entering side of the shuttle. This expects the threading to start at shaft 1 and be complete (end on an even shed).

No floating selvages are needed!

 

 

Here is how to tell on paper:

The figure below shows that when entering the shuttle from the right, there is no warp to catch the weft at the other end.

 

 

This figure below shows that when entering the shuttle from the left, there is a warp to catch with each shot.

 

 

4.  What is the most efficient way to tie-up a 6-treadle, 4 shaft loom for a pointed twill to be woven tromp as writ?

There is not an absolute answer to this, it does depend on the ergonomics related to the loom and your preferences, but you should always disconnect treadles that are not in use to minimize errors.

Here are two possible ways for the tie-up.

The standard way is shown in blue below (only 4 treadles in use, two are disconnected, generally one on the right, one on the left). The aqua section shows what happens if you forget the location of your repeat. You just wove 3 & 4 – what’s next, 1 & 4 or 2 & 3?

 

 

The second way to tie-up is what I prefer shown in the pink drawdown below. I use the extra 2 treadles to double tie for 4 & 3 and for 2 & 3 which are used twice. Then the treadling is across the 6 treadles.

 

 

Let’s take a detour. In the drawdowns, which of course are identical, the pattern starts in the middle of the repeat. Patterns are written for convenience, but they are not necessarily how we want to weave them.

 

 

Compare the original pink drawdown on the left with the green drawdown on the right. The pattern is the same, but the threading has been adjusted so that the repeat starts with the beginning of the pattern.

Does this pattern needs floating selvages? Yes! No matter where we start, the weft won’t be caught at the selvages.

 

 

5.  What is the most important difference between twills and satins?

Using Emery’s classification, twills are defined as progressive successions of floats in diagonal alignment (pink weft).

Satins are intermittent progressions of floats and suppression of the appearance of diagonals (yellow weft). The apparent diagonal is not formed by adjacent threads.

 

 

6.  How would you weave plain weave across the width of a 7-shaft satin fabric?

The straight draw in the drawdown below is a 7-shaft satin.

 

 

To weave plain weave, we need to activate two sets of alternating threads in succession.

The pink threads in the threading below show that it is not possible to alternate. No plain weave across the fabric is possible.

 

 

This method works with any threading.

But the original question asked “How would you weave plain weave across the width of a 7-shaft fabric?

It depends on the fabric. First example is huck:

Huck has blocks that alternate shafts 1 and 2 as the delimiter. It is possible to weave a 7-shaft huck, but block using shaft 1 must alternate with those using shaft 2.

Below is one example: block E (2, 7) is followed by block D (1, 6).

Plain weave is woven 2 & 4 & 6 vs. 1 & 3 & 5 & 7.

 

 

The next example is Bronson Lace, drawdown below.

In Bronson Lace every block uses shaft 1, which alternates with other shafts depending on the block.

Plain weave across the fabric then will be 1 vs. all other shafts.

In this case 1 vs. 2 & 3 & 4 & 5 & 6 & 7.

 

 

Below is an example of summer and winter, a tied weave.

The tied weaves have various shafts for ties and the rest of the shafts for blocks.

Ties vs. shafts in  many cases form plain weave for the ground.

Our summer & winter uses shafts 1 & 2 for ties and, in this example shafts 3-7 for blocks, one shaft per block;

S & W plain weave is 1 & 2 vs. 3 & 4 & 5 & 6 & 7.

 

 

7.  What is the difference between Huck and Huck Lace?

In huck (blue & pink weft in the drawdown below) when one block weaves floats, the other weaves plain weave.

In huck lace (yellow weft), one block weaves weft floats, the other warp floats.

With more than 4 shafts, the two are often combined.

 

 

 

8.  Why is the unique difference between Huck and Bronson? (Bronson-Atwater)

In Bronson lace (the drawdown below) blocks can be combined, no matter the number of shafts.

 

 

On 4 shafts, in huck (the drawdown below) blocks cannot be combined with the same float (huck lace combines weft and warp floats as we saw above).

In huck with more than 4 shafts, blocks with the same tie-down thread can be combined.

 

  

I hope this exercise helped you in the understanding of these structures.

Happy Weaving!

Marcy

 

 

A Wonder Year of Weaving

Marcy Petrini

May, 2021

I am leading a group of adventuresome weavers in a year long quest to learn as many structures as we can. Based loosely on my monograph by that name, which was prepared for a one-day workshop I taught at Convergence in Reno, this iteration takes a whole year; we meet monthly on zoom, I provide some basic information, participants do research and weave, sometimes samples, sometimes pieces, and sometimes life gets in the way, so they skip the month weaving.

During the meeting we go over the material from the past month, we have a show and tell with pictures of the work done and then we prepare for the following month. We record it all and then it is posted on my website by month, along with the all the supplementary material (click here for the link).

We are following the weave structures as described by Irene Emery, The Primary Structures of Fabrics, and during the last four months, we have been studying what Emory calls “simple weaves” – simple not by complexity, but because they have one set of warps and one set of wefts. The weaves are: plain weave, twills, satins and float weaves derived from plain weave, sometimes called rectangular float weaves, which include the lacey weaves (lacey to me because they do not form true lace, the lace makers tell me).

Since we are done with the simple weaves, it seemed like a good time to stop and assess what we learned. In a group this varied, which include people who could be leading it to beginners, it’s good to make sure that we haven’t missed anything from the big picture.

Here are the 8 questions, 2 per month, that I posed to the group. The instructions are to try to answer as many as possible from knowledge, but then to look up what they don’t know, have forgotten or need to check.

How well can you answer these questions?
(Click here for the 9-slide PDF version.)

 

What is the difference between tabby and plain weave?

 

How would you adjust the warp sett to weave a weft-faced fabric?

 

What is the best option for nice selvages on a straight twill woven as a straight draw?

 

What is the most efficient way to tie-up a 6-treadle, 4 shaft loom for a pointed twill to be woven tromp as writ?

 

What is the most important difference between twills and satins?

 

How would you weave plain weave across the width of a 7-shaft satin fabric?

 

What is the difference between Huck and Huck Lace?

 

Why is the unique difference between Huck and Bronson? (same as Bronson-Atwater)

 

 

Happy Weaving!

Marcy

 

 

Zoom to Satins and False Satins

Marcy Petrini

April, 2021

 

When the pandemic lock-down took place, I was in the middle of teaching an in-person twill class at the Craft Center. At first, we were on hold, but as the pandemic continued, I was reminded of how much I missed teaching.

Enter zoom: I had read pros and cons of using it and how some things can only be taught in person. Maybe. We finished the twill class with successful projects and we embarked in a lacey weave class for the rest of 2020, again with successful projects. Using e-mails, phone calls and sending photos all helped. Well, we can’t touch the fiber or finished project, that’s true, but that’s also true for books, magazines, and the rest of the internet.

Talks, seminars, an interview, and now a study group on zoom all followed. In some ways it’s magical. I meet with people from all over the country; I have given seminars in the US as well to a wonderful guild in Canada; more seminars are scheduled – all from the comfort of my studio.

And even more important, my learning continues, not only from my own researching to teach and present, but also from students and participants. In the diverse group that comprises our study group, the breadth of knowledge is impressive.

For the study group month on satins and false satins I was reminded that sometimes I have forgotten to tell weavers that we cannot just duplicate the reverse of the tie-up to alternate the treadling between sateen (weft-dominant side) and satin (warp-dominant side). (See May and June 2017 blogs).

Let’s look at a 5-shaft satin:

 

 

The 5-shaft satin should have floats over 4 threads. In the drawdown above, at the joints between satin and sateen, the floats are longer, 5 threads.

This problem occurs regardless of the number of shafts used and also for false satins, shown below, where the float length should be 3 threads, but it’s 4 at the joints.

 

 

When we have blocks, whether of false satin as shown below, or true satin, the longer floats appear in both directions.

 

 

This may not be very obvious in the fabric, but it does break the rule of the satins and false satins, so it is worth to find an alternative.

Recently, I have been showing a way around the floats which is not standard. It is to stagger or offset the second section of the tie-up from the first. Here is an example for the 5-shft satin where the tie-up for the satin is offset from the sateen tie-up by one shaft:

 

 

This actually works as the floats in the above example are never more than 4-threads long. However, there is a much better and elegant solution: using the mirror image.

I learned about mirror images from books by Doramay Keasbey, but I had totally forgotten about it until Debbie Cummings came to the rescue! In researching satins, she found this true-and-tried method. It works for satins and false satins, for switching from sateen to satin and for blocks.

Below is the drawdown for the sateen and satin treadling for a 5-shaft satin.

 

 

The drawdown for the mirrored false satin for the two treadlings is below:

 

  

When weaving false satin blocks, all quadrants of the tie-up are mirrored as shown in the drawdown below:

 

 

Once we are comfortable with the concept of satins and false satins, it is actually easier to weave them by threading a straight draw and using the satin rules for the tie-up, mirrored for the sateen and the satin. This is shown in the drawdown below.

 

I am grateful for the opportunity that Zoom offers to carry on the teaching – and the learning.

 

Happy Weaving!

Marcy