Originally posted on Creative Stack: Episode 4: Forms Hook Functions
When I explain to people that I’m using a knitting machine, they quickly assume that the machine does all of the making. In reality, it’s a collaboration between the user and machine. This is my favorite part — each step is facilitated by the user through casting on, moving the carriage, twisting stitches, fixing dropped stitches and more. The machine facilitates which needles to move, how to move them and how each thread hooks to the needles.
As an avenue to learn machine knitting, a few collaborators, Liza Stark, Victoria Manganiello and I decided to start a swatchbook to document our progress and findings as we learned how to use the Brother KH910 Electroknit Knitting Machine.
Why a Swatchbook?
Traditionally associated with craft and textile work, a swatchbook is a booklet that contains samples demonstrating a particular fabrication technique. I have been inspired by The E-Textile Summer Camps Swatchbook Exchange, “a platform for sharing physical work samples in the field of electronic textiles. Individuals and collaborative efforts participate in the exchange by submitting a unique swatch design of their own, and in turn receive a compiled collection of everybody else’s swatches. The exchange wishes to emphasize the importance of physicality and quality workmanship in an increasingly digital world”. I’ve never participated in the swatch exchange, but I have had the pleasure of looking through a few iterations of the swatchbook. When you hold the booklet, it feels full and bulky — filled with samples of eTextile swatches. The book possesses a presence as part art artifact, documentation and community sharing.
A Tour of Our Swatches
Machine Knitting 101
To kick off our machine knitting swatches, we started with the basics. First up, learning how to cast on and off the machine. We tried the cast-on comb and e-wrap cast-on methods, and the loop-through-loop and latch-hook bind off methods. As a group, we all quickly gravitated towards our favorites, typically choosing different approaches. After multiple iterations of our cast-on and cast-off methods were solid, we tried eyelets, ladders, a simple hem and a honeycomb pattern.
Knit Side of Honeycomb Pattern
Purl Side of Honeycomb Pattern
AYAB
The 3D structure of the honeycomb swatch left us wanting to explore and experiment creating varying knitted textures and patterns. We decided to use the knitting machine needles to transform our swatches into soft pixels with All Yarns Are Beautiful (AYAB). AYAB is an open-source project that provides an alternative way to control the Brother KH-9xx range of knitting machines.
The KH-910 knitting machine was originally created and programmed to use semi-transparent picture cards that are scanned by the machine. Using the line-by-line data, the machine changes the needle positions to knit the image on the picture card. The picture card is two-toned (white and black), and each knitted pixel can be represented using two different-colored yarns. Using the AYAB hardware, the knitting machine can be connected to a computer and a digital image can be uploaded.
The AYAB hardware comes in two forms, a custom-developed shield for arduino or the AYAB interface created by Evil Mad Scientist Laboratory. To use the interface, you simply open the knitting machine and replace its control board with the AYAB controller. The interface pairs with the AYAB software.
The KH910 knitting machine with the AYAB interface plugged in and the original controller sitting behind the machine.
Visiting upstate New York for a week of making, we decided to use our surroundings as inspiration and set up the knitting machine in the front yard. We took a photo of the bark on a tree in front of us, turned the image to a pure black and white scale, and knitted the outcome.
Image of the tree with a threshold filter
AYAB software interface with bark image uploaded
Knitted eTextile Swatches
Electronic textiles, or eTextiles, embed electronics and electrical circuits into textiles using conductive fabrics, yarns, threads and other materials through craft, fabrication or industrial techniques. For our knitted eTextile swatch, we decided to start with a simple design to see how the machine would work with copper thread. Copper thread is much stiffer compared to yarn, so we had our doubts. The design consisted of two circuit paths (i.e., leads) of copper thread knitted in the middle of our swatch. Each copper path was coupled with thin yarn as a reinforcement.
Swatch with two knitted copper thread paths
Next, we decided to create a knitted stretch sensor. A knitted stretch sensor is made of conductive yarn, and when stretched, the resistance of the material changes.
Stretch Sensor Diagram by Liza Stark
Our initial design was to create a square swatch with a long tube in the middle that could be pulled (picture a sock in the middle of a knitted square). The tube would be created using conductive yarn and the square base would be created using regular yarn. We wanted the piece to be knit in one pass and did not want to attach two separately knitted pieces together. Not knowing exactly where to start, we browsed through Knitting Techniques Book by Brother Industries Ltd., 1984 and decided to try partial knitting.
After a few attempts of partial knitting, the tube structure was more of a hammock structure with two holes on each side. Looking at our “failed” swatch, we realized these hammocks were perfect finger pockets. With two pockets on each swatch, two fingers could sit in each hammock and stretch the material — this would create two knitted stretch sensors that could be used as analog inputs with an arduino board. Excited by this, we quickly wrote up a pattern for a Knitted Finger Pocket Stretch Sensor. Inspired by how Annie Larson writes her knitting patterns, we drafted ours using them as a reference. Below you will find the pattern for the Knitted Finger Pocket Stretch Sensor. R# refers to row # (i.e. R0 == the first row, typically the row that is casted on).
R0 - Cast On (e-wrap or latch tool; carriage starts on right side)R1 - R16: KNIT -- Set up Partial Knitting; Set carriage to “H” ; Bring needles 1-20 and 30-50 to E positionR17 - R42 KNIT Watch out for dropped stitches here. -- Set carriage to “N”R43 - R58 KNIT-- Set up Partial Knitting; Set carriage to “H” ; Bring needles 1-20 and 30-50 to E positionR59 - R84 KNIT Watch out for dropped stitches here. -- Set carriage to “N”R85 - R100 KNIT-- Bind off. Consider knitting the final row at a larger gauge to aid bind off. 
Knitted Finger Pocket Stretch Sensor Swatch
Why a Knitting Machine?
Working with the swatchbook approach is helping us learn what is possible with the machine. By learning new techniques, we are inspired by how the material and machine work together, discovering new ways to experiment along the way. We plan to create a full swatchbook with many experiments. Follow us along @etextiles to see our progress.
References:
Knitting Techniques Book by Brother Industries Ltd., 1984
This article was written by Nicole Yi Messier for Creative Stack in August 2021