In Defense of Weaving Classification

Marcy Petrini


February, 2024

In the early 90’s I became aware that weaving structures could be classified to help us understand them. Donna Sullivan published her book Summer & Winter A Weave for All Seasons and came to teach the workshop to my local guild. She introduced the classification for tied unit weaves which, however, were still pretty overwhelming to me. I promised myself that I would spend some time to learn more in the future. 




From then on, any time I came across a tied unit weave in a publication or sample, I would look at the block threading and treadling and make a drawdown. It was filed electronically in a subdirectory for that purpose.

Times goes fast when you are having fun, but finally I wanted to be serious about understanding tied unit weaves more fully. I submitted a proposal for Convergence® 2020 on the subject. It was accepted, but as we all remember, it wasn’t until 2022 that the conference actually occurred. Having a deadline and a purpose is a good way for me to focus.

I decided that I would use Donna’s book and systematically try to understand the blocks by changing the various parameters that she discussed.

I have talked about her classification before, but here it is again to simplify the discussion. It is based on the threading:


double, etc.

Number of pattern shafts
per block

# Tie shafts

Number of shafts
for the tie-down threads


the ties are next to each other
or not


# of tie-down threads
# of pattern threads
within a block


Summer and winter is a single, two-tie, unpaired weave with a ratio of 1:1.


From the threading we see that each block has one pattern shaft, block A 3, block B 4. Hence the single designation.

There are two ties, on shafts 1 and 2.

The two ties are not next to each other, they are separated by the pattern shaft, hence unpaired.

For each block, there are two pattern threads, albeit on the same shaft, and two ties; 2: 2 or 1:1 ratio. In this case the ratio is not needed as the rest of classification makes it unique to summer and winter.

As I was studying these structures, I thought: how about a single, two-tie paired structure? I couldn’t find one, so I did a drawdown following the classification directions.

Since the single, two tie paired can be woven on four shaft, I started the paired option on four shafts. (This and following drawdowns are sinking shed).



It is feasible. It doesn’t weave plain weave across the fabric, but that happens with other tied-unit weaves as well. I decided to weave it. Since the Convergence® seminar was on eight shafts, I expanded the four shaft version above to eight shafts and wove it. Below is the drawdown and the fabric front and back.








This was the first benefit of the classification: finding other options that may not have been previously published. Someone else may have tried it and not liked it, but I rather like the fabric.

The structure does require fourteen treadles to weave, but it can collapse to 10 by using two feet. If you don’t know how to do that, you will just have to read my “Right from the Start” in the summer issue of Shuttle Spindle & Dyepot.

I woven as many samples as I could, mostly individual blocks. There are various motifs published that combine blocks, and that is a great option for weaving, but I wanted to understand the blocks first – and I wanted others to do the same. The design comes later.

Finally, it was time for Convergence®. Most but not all of samples for the monograph were woven, but I did have drawdowns for all the ones I wanted to discuss. There were a few in my “to weave” list and I am sure there are others. I will continue to search for them and weave them as the opportunity arises.

After my seminar, one of the attendees came up to me to tell me that she enjoyed my seminar, but she was surprised that I didn’t include Quigley in my collection of weaves. I told her that I ran out of time, but that Quigley was on my list to do, especially since she was one of my “neighbors.” She founded the Memphis, TN Weavers Guild, one of my weaving friends from that guild told me.

I will be teaching a seminar at the upcoming Convergence®, on blocks in general, so I have been thinking about tied unit weaves again. Time to weave Quigley, I thought.

I started planning it with the drawdown below.



I was in the middle of the second block when I said to myself: “wait a minute, that’s a single, four unpaired ties with a 1:1 ratio – I have that in my monograph, the drawdown, not the sample.”

And sure enough, the following drawdown is in my monograph. It’s fun to give credit to the weavers who came before us and designed these weaves, but unless we use the classification, we don’t really know what these structures are.




I wove the sample below, front and back, just in time for my recent zoom workshop for the Intermountain Weavers Conference.






But there is more. Recently I was looking for Quigley in my files and I know that Robin Spady has woven it with different treadlings, and Louise French had an interesting treadling for a sample in the Cross Country Weavers notebook. Now that I know what Quigley really is, I can pay full tribute to my “neighbor.”

Happy Weaving!