As seen in . . . Overview of mechanisms Manual Dobby

A manual dobby uses a chain of bars or lags. Each bar has pegs inserted to select the shafts to be raised. Each bar equals one pick. During the process, the Is a dobby loom in your future? chain moves bar-by-bar. Often, there are two treadles that alternate. One treadle is used to lift the shafts and the other treadle tells the dobby to go to the next weft pick. The pegs Do you love to weave, but find complex patterns beyond placed in the bar tell the dobby which shafts to lift - almost the capabilities of your loom or find yourself spending like a chord being played on a piano. The length of the more time searching for the right treadle for your next treadling sequence is limited by the length of the chain. pick? Then, a dobby loom may be in your future.

What is dobby?

Many people became introduced to the name Dobby, a house elf, in the Harry Potter movie series. This is something completely different. When applied to weaving, the origin of the term dobby may be from the 17th century and inspired by Dobby, a pet name form of Robert. According to the Dictionary, the term may be “an extension of the earlier sense ‘benevolent elf’ (who performed household tasks secretly)”. It has also been suggested dobby is based on the term draw boy, which refers to the person assisting the weaver by pulling on the warp ends.

A dobby loom is a floor loom with a device, called adobby , that controls the shafts. Dobby first appeared Close-up of AVL’s manual dobby around 1843, roughly 40 years after Joseph Jacquard invented the Jacquard loom, which controls individual warp threads.

Louët Megado (left) and Octado (right) manual dobby looms

Computer-interfaced Dobby Loom A computer-interfaced dobby loom takes weaving with a dobby one step further by replacing the mechanical Dobby loom, 1890 dobby and chain of bars with a device that interfaces with a computer or memory stick. The treadling sequence is A dobby loom is an alternative to a multiple-treadle loom. controlled by the weaving software application on the Like a traditional floor loom, every warp end is threaded computer. This allows the weaver to make corrections or through a , the heddle is on a single shaft, and each completely change the treadling in seconds. shaft controls a set of threads. Raising or lowering the shafts in different orders creates a variety of possible sheds A computer-interfaced dobby loom uses a set of solenoids through which the , containing the weft thread, may or other devices to select the shafts. Activation of these be thrown. Unlike a traditional floor loom, with multiple solenoids is under the control of a computer application. treadles tied to the shafts, a dobby loom is not limited by In either case, the selected shafts are raised or lowered by a the number of treadles on a loom. treadle or pedal.

44 Heddlecraft® Advantages of dobby looms

• Overcome treadle limitations - A warp end is up or down. However, as the number of shafts increase, so do the number of possible combinations. Even with a four-shaft loom, the potential for running out of treadles is possible since there is 14 different ways to tie-up a treadle. With four shafts, a direct tie-up (each treadle tied to a single shaft), is possible to overcome treadle limitations since a weaver’s two feet can manage the four treadles. Unfortunately, a direct tie-up will be of limited use very quickly as the number of Close-up of AVL’s CompuDobby® shafts increase. external and internal view Total number of treadle tie-up combinations 4 shafts = 14 8 shafts = 254 16 shafts = 65,534 24 shafts = 16,777,214 32 shafts = 4,294,967,294 (Yowza!) (For those with inquiring minds, the mathematical formula is as follows: 2 to the nth power minus 2 when n equals the number of shafts.)

• Improved treadling efficiency - Tracking a treadling Louet Megado V2 Electronic Dobby sequence can be ominous when the sequence is long, complicated, or irregular. Once the dobby loom is set-up and read-to-go, the treadling sequence is largely dependent on the dobby chain or the computer and weaving software application. • More ergonomic - Since dobby looms are limited to two treadles or a pendal, they are located near the TOIKA’s computer-interfaced dobby head center of the loom. While treadling, the weaver will have better leverage compared with reaching to the outside to press a treadle. • No crawling under looms - Corrections and changes to the treadling sequence don’t require crawling under the loom to change the tie-up. • Quick and easy changes - With a computer-interfaced dobby, changes and corrections to treadling sequences can be made quickly and easily with a couple of keystrokes or mouse clicks.

TOIKA Eeva computer dobby loom Myths and misunderstandings of dobby looms

• Weaving is not automatic - Weaving on a dobby loom still requires the weaver to warp and thread the loom, properly set up the dobby mechanism, treadle the loom, and throw the shuttle. • Dobby looms are not new - As mentioned earlier, dobby looms have been around for nearly 200 years. • It’s not cheating - A weaver still has to perform all of the tasks associated with weaving. Dobby looms assist with the treadling sequence. Leclerc Weavebird computer dobby loom

May/June 2018 45 • Dobby looms are large - Some dobby looms can be - Making corrections or changes in the treadling quite large; however, there are a few with weaving sequence is laborious. widths 24” or under. The following are just a couple of the small dobby looms currently available. - The treadling sequence is not easily observed in a dobby chain.

• Computer dobby loom - There are a couple of challenges in setting up and using a dobby loom that interfaces with a computer. - In addition to the dobby, a computer and weaving software is required. This can increase the cost and the learning curve.

- Without power, weaving cannot commence. Although, that could be a good time to work on other things. Leclerc Diana 24” 16-shaft Computer Dobby Loom • Complacency - It’s easy to become overly-confident while weaving on a dobby loom. Dobby looms, manual or computer-interfaced, are not void of issues and making errors. Stepping on a treadle incorrectly can impact the way the dobby communicates with the loom.

For more information

AVL https://www.avlusa.com/catalog/looms/ • Little Weaver (available 2019) • Workshop Dobby Loom • Studio Dobby Loom • A-series • K-series AVL 24-shaft Workshop Dobby Loom • V-series • Industrial Dobby Loom Disadvantages of dobby looms • Professional Dobby Rug Loom

• Learning curve - Understanding how to set-up and LeClerc operate a dobby loom adds to the weaving learning http://www.leclerclooms.com/cat2014a.htm curve. Not only must one learn the fundamentals of • Diana weaving, learning how to set-up a dobby loom, operate • Weavebird the software, and troubleshoot problems can seem daunting. Louët https://www.louet.com/dobby-looms/ • Weight - As the shafts increase, it may increase the • Megado amount of weight to raise the shafts for each weft pick • Octado without a lift-assist of some kind. • Magic • Manual dobby looms - Even without a computer- interface, there are several challenges. Toika https://www.toika.com/en/tuote/computer-looms/ ­- The effort to prepare the dobby chain (screwing in • Eeva dobby pegs, positioning it properly in the dobby • Liisa head, etc.) can be tedious and time consuming. • Jaana - The weight of the dobby chain increases with the length of the treadling sequence and may exceed what the dobby can manage. Some weavers have had to get creative in suspending the dobby chain to alleviate the weight on the dobby. 46 Heddlecraft®