How it all works
My loom is a 4-harness, 4-treadle countermarch walking loom with a shaft switching device per Peter Collingwood, which I designed and built myself. Standing while weaving allows me to weave longer and the shaft-switching device allows almost infinite design flexibility as well as faster weaving.
Click the header picture on each page for an explanation of what it's showing.
The very basics of weaving
Warp is the yarn tensioned by the loom. When weaving, warp threads are spread apart (some go up, some go down) to make space for a shuttle full of weft yarn to go through (from side to side). The weft is pressed into place by the beater. When different warp threads are spread apart and another weft yarn is passed through and beaten in place, an interlacement is made, which makes cloth.
Tying on the warp
In order to tension warp, it has to be tied to something at both ends. At the end of the loom opposite the weaver, the warp attaches to the warp beam. As the process of warping a loom is long and slow, I wind enough warp yarn for multiple rugs on the warp beam at once. If I’m in the middle of weaving off 36” wide rugs and you commission a 48” wide rug, there will be a delay before I get to your rug.
At the weaver end of the loom the warp attaches to the cloth beam via the apron. The apron is a piece of canvas attached to the cloth beam at one end and the warp at the other end, and fills in the gap between where the rug is woven and where it is wound onto the cloth beam to reduce warp waste. As weaving progresses and warp is turn into cloth, the apron and then the rug wind onto the cloth beam.
A piece of 1/2" steel rod goes through the loops on the warp end of the apron, but those loops would distort how the warp lies if the warp bundles were attached directly: they're too wide. So there're two 1/4" steel rods attached to the 1/2" rod with loops of linen yarn (which doesn’t stretch), and the warp is attached to the 1/4" rods with a continuous piece of linen yarn.
Tensioning the Warp
Rug looms are built stoutly to take high warp tension, as high warp tension allows the weaver to pack the weft thread tightly and make a solid, durable rug. (Cheese-cloth makes poor rugs.)
Books have been written on the art of tensioning warp yarn for weaving rugs, as rugs won't lie flat if it's done incorrectly. Having studied Peter Collingwood's books on rug weaving, I use the moving beam tensioning method.
If you look closely, you'll see that the warp comes off the warp beam (which never moves while weaving a particular rug), goes up over a moveable beam, down under another moveable beam, over the immovable back beam (which has nails in it to help position warp threads), and then onward to the harnesses.
If I were to unroll warp from the warp beam, yarn threads lying in a valley between other warp threads would be shorter and more highly tensioned than warp threads lying directly on top of other warp threads. The effect is cumulative, and makes for rippled rugs. Instead, I get more warp to weave into a rug by moving the moveable beams toward each other. As the warp over the moveable beams is single layer, tension doesn't change.
Heddles within harnesses
When the warp gets to the harnesses, it is threaded through holes (eyes) in the heddles. Heddles are made of string, or nylon, or steel, and are held taut by the harnesses, which are just a wood and steel framework. When the harnesses are moved up and down by the Texsolv cords attached to the lamms and treadles, the warp captured within the eyes in the heddles also moves up and down, making the opening that the weft thread on the shuttle goes through.
On my loom, it’s a bit more complicated than that, as I use a shaft-switching device explained below.
Lamms are attached with Texsolv cord to the treadles below them and to the harnesses above them. They pivot at one side of the loom. When I step on the treadle, the lower set of lamms pulls harnesses (and the warp) up, and the upper set pulls them down, making a large opening for the shuttle to go through.
Why bother with lamms? Why not just tie one treadle to one harness? Two reasons: lamms allow you to tie multiple harnesses to one treadle (making up for having only two feet), and only pulling down on some harnesses (without pulling up on the others) makes a smaller opening for the shuttle.
On my loom, the treadles are hinged behind me and are attached by Texsolv cord to the lamms at their other end. I stand to weave, and control which harnesses go up and which go down by shifting my weight from one treadle to another (hence a walking loom).
Because my treadles are hinged, they have a tendency to move laterally. The picture shows the treadles going through the cage I built to keep them from overlapping and hanging up on one another.
The beater and beater hanger
Once the warp is through the harnesses, it is threaded through the stainless steel reed in the beater. From there, the warp yarn is attached to the apron. The warp becomes cloth in the area between the beater and the apron. The reed is tall to accommodate the separation of the warp threads, as the shuttle passes through the warp on the weaver’s side of the reed.
The reed not only separates each warp thread from its fellows, it is used to pack the weft threads in tightly, making a firm rug. The reed is held snugly, top and bottom, in slots cut in pieces of wood that are attached to a 30 pound bar of right angle steel. Both the steel bar and the wood pieces are attached to square, steel tube uprights. The top piece of wood is what I grab to swing the beater.
Since momentum is what packs the warp and momentum is weight multiplied by speed, increasing the weight of the beater decreases the wear on the weaver. Hence a 30 pound weight, nothing I’d want dropping on my feet. That heavy weight requires the square, steel tube uprights. Those uprights have holes drilled through the wooden blocks inside.
There's a bolt through a hole at the top of each upright, and that bolt is threaded into a much-longer-than-normal nut. The nut sits in the v-notch, and can be moved from notch to notch to move the beater to its optimal position. As the beater swings back and forth, the bolt rotates back and forth in the nut.
The shaft-switching device
The shaft-switching device (consisting of a framework, levers, and Texsolv loops) is the brainchild of Peter Collingwood, who generously shared it with the weaving community. Using it allows the weaver almost infinite control of where a color appears on the front or back of the rug.
On harnesses 2 and 3, warp yarn threads through the eyes of the heddles: this controls the interlacement. On harnesses 1 and 4, warp yarn threads through the center eye on a Texsolv loop. That loop threads through the eyes of the heddles on 1 and 4 and is attached to the free end of the lever. If the lever points forward, the loop snugs the warp thread to 4, and that warp thread goes up and down with 4. If the lever points backward, the loop snugs the warp thread to 1, and that warp thread goes up and down with 1.
The Texsolv loops of the shaft-switching device attach to the levers by being threaded through holes in the levers' ends. Tiny jewelry jump rings are used to attach the ends of the loop to one another on each side of the hole, keeping the loop from shifting.