Loom Parts Glossary

Somewhere between deciding to weave and actually weaving, you meet a wall of vocabulary. A pattern tells you to sley the reed. A secondhand listing mentions four harnesses and a raddle. Someone asks what sett you are using, and you are not sure whether that is a measurement, a setting, or a verb.

Most loom parts make sense as soon as you watch them move. Before that, the names can feel surprisingly opaque. This loom parts glossary explains what each piece does at the loom, how related terms differ, and which details matter when you are threading, weaving, or evaluating a loom.

What Is a Heddle?

A heddle is a cord, wire, metal strip, or loop that controls a warp end on a loom. Most heddles have an eye at the center. During threading, a warp end passes through that eye. When the shaft carrying the heddle moves, the warp end moves with it and helps open a path for the weft.

That is the basic idea: one heddle controls one warp end in an ordinary threading. Once each end is assigned to a heddle and shaft, the loom can raise or lower groups of threads in a planned order. You may also see the word heald, especially in British weaving references. It names the same part.

Rigid Heddles Versus Individual Heddles

The term gets confusing because two different objects share it.

A rigid heddle is a removable panel with alternating slots and holes. The warp ends in the holes move with the heddle. The ends in the slots can slide vertically within those slots. Raising or lowering the panel separates the two groups and opens a shed. The panel also spaces the warp and beats the weft, combining work that a shaft loom divides among heddles, shafts, a reed, and a beater.

This double duty explains why rigid heddles are sold by dent size and why Schacht calls its replacement panels Schacht Rigid Heddle Reeds. The name sounds contradictory until you see the tool doing both jobs.

Individual heddles hang on shafts. A shaft loom needs at least one heddle for every warp end in the project, plus a practical supply of extras. The right inventory depends on the loom width, planned sett, and how the ends are distributed across the shafts. A wide, finely set warp can use far more heddles than a narrow scarf on the same loom.

Common heddle materials include:

• Texsolv polyester heddles are lightweight, quiet, and resistant to rust. Their open construction also makes them easy to move along a shaft. Lojan Texsolv Heddles in 160 mm packs of 100 are a replacement option for looms designed for that heddle length.
• Flat steel heddles keep a crisp, orderly position on the shaft bars. Many weavers appreciate how easy their eyes are to see while threading.
• Inserted-eye wire heddles have an enlarged eye designed to give the yarn a smoother passage through the center of the heddle.
• String heddles can be tied by hand and remain useful on inkle, tapestry, and other simple looms.

Match replacement heddles to the loom and its shaft-bar spacing. Length matters. If older metal heddles have rough rust or pitting around the eye, inspect them closely before dressing the loom. A rough spot can abrade a fine or softly spun warp during hundreds of shed changes.

Three parts that get confused, and the job each one actually does.

• Rigid heddleSpaces the warp and lifts it. One board does both jobs, which is why a rigid heddle loom needs no shafts.
• ReedSpaces the warp and beats the weft into place. The gaps are dents, and dents per inch sets your sett.
• HeddlesLift the warp, nothing else. Each eye carries one thread, and the shaft they hang on raises them together.

The Shed and the Parts That Open It

Shed is the opening between raised and lowered warp threads. The shuttle carries the weft through this opening. From the side, a clear shed looks like a long triangle whose point meets the fell of the cloth.

A clean shed gives the shuttle room to pass without scraping across warp ends. When the shed feels sticky or shallow, check for crossed threads, heddles caught on one another, uneven tie-up cords, or warp tension that varies from edge to edge.

Shaft, also called a harness or heald frame, is the frame that carries a group of heddles. When a shaft rises or sinks, every warp end threaded through its heddles moves with it. The number of shafts affects the weave structures available, while the threading, tie-up, and treadling determine the pattern woven on a particular warp.

Castle is the central structure that supports the shafts and part of the lifting system. It is the upright section that gives many table and floor looms their familiar tower-like profile.

Treadles are the foot pedals on a floor loom. A treadle operates a selected shaft or combination of shafts, leaving both hands available to manage the shuttle and the cloth.

Lamms are horizontal levers between the treadles and shafts on many floor looms. Their exact arrangement depends on whether the loom uses a jack, counterbalance, or countermarch system. In each case, they transfer treadle movement through the loom's lifting or sinking mechanism.

Tie-up is the system of cords or connectors that assigns shaft movement to the treadles. Changing the tie-up can change the sheds produced by each treadle, but it still works within the threading and shaft arrangement already on the loom.

The Reed, Sett, and the Parts That Build the Cloth

A reed is a comb-like tool held in the beater. It spreads the warp across the weaving width and beats each new pick of weft into place. Reeds are commonly made from stainless steel, although other materials appear on some looms.

Dents are the spaces between the wires or blades in a reed. A 12-dent reed has 12 spaces per inch. Metric reeds may instead be labeled by dents per centimeter or dents per 10 centimeters, so check the unit before planning the sett.

Sett is the number of warp ends in a unit of width, most often written as EPI, or ends per inch. Dent count belongs to the reed. Sett belongs to the cloth plan. A 12-dent reed can produce 12 EPI with one end per dent, 24 EPI with two ends per dent, or other setts by using a repeating sleying sequence.

Sett changes with yarn size, yarn structure, weave structure, and the hand you want in the finished cloth. A wrap-per-inch measurement can offer a starting point, but it cannot predict the finished fabric by itself. The reliable method is to consult a project or sett reference, weave a sample, and wet-finish that sample. Cloth under loom tension often looks more open and rigid than it will after the yarn relaxes, blooms, or fulls in washing. Our yarn weights guide can help you identify the yarn before you begin sampling.

Beater, also called a batten, is the swinging or sliding frame that holds the reed and carries it toward the fell. To sley the reed means to draw the warp ends through the dents. Some regional and historical sources also use sley for the reed itself, so context matters.

Fell is the edge of the woven cloth where the newest pick of weft has been placed. Keeping the fell in a comfortable working zone helps the shed open cleanly and keeps the beater's movement consistent.

Shuttle race is the smooth ledge below the reed on many floor looms. It supports a boat shuttle as it travels across the shed. Some looms, including many counterbalance and countermarch designs, have an open shed without a shuttle race.

The Four Loom Beams

Several horizontal parts run across a floor or table loom. They are easy to mix up until you follow the path of the warp from back to front.

Warp beam is the rear roller that stores the unwoven warp under tension.

Back beam, sometimes called a whip roll, guides the warp from the warp beam toward the shafts. It helps establish the height and angle of the weaving plane.

Breast beam is the front beam over which the woven cloth passes. It helps set the front of the weaving plane before the cloth travels down to the cloth beam.

Cloth beam is the front roller that stores the fabric already woven.

Aprons, apron cords, and apron rods connect the warp or cloth to the beams. They bridge the distance between the beam and the working warp, reducing loom waste and distributing tension across the width.

Ratchet and pawl describes a toothed wheel and locking catch used to keep a beam from unwinding. Many looms use ratchet-and-pawl systems on one or both beams. Others use a friction brake on the warp beam and a separate cloth-advance mechanism. Learn which system your loom uses before releasing tension, because the controls can look similar while working differently.

Warping Tools You Meet Before You Weave

Five objects that show up in every used loom listing, and what each one is for.

• RaddleSpreads the warp to its full width as it winds onto the back beam.
• Lease sticksHold the cross so every warp thread stays in order.
• Stick shuttleCarries the weft. Flat, simple, and best on narrow work.
• Boat shuttleHolds a wound bobbin so the weft feeds smoothly at speed.
• Pick-up stickLifts chosen warp threads to build pattern by hand.

A raddle is a bar with evenly spaced pegs, teeth, or slots. In back-to-front warping, it spreads the warp to its planned width while the warp is wound onto the beam. Even spreading at this stage helps the layers build evenly and supports consistent tension later. Leclerc Raddles are available in sizes matched to several Leclerc looms.

Lease sticks are a pair of smooth sticks placed through the warp cross. The cross preserves the order of the ends, making each thread easier to identify during threading. Secure it carefully. Recovering the order of a large warp after losing the cross can turn a calm warping session into hours of sorting.

A warping board or warping mill helps you measure warp ends to a consistent length and build the cross before dressing the loom. A board holds fixed pegs on a frame. A mill rotates, allowing long warps to be wound with less reaching.

Shuttles carry the weft. A stick shuttle is a flat, notched tool that works well for narrow pieces, simple looms, and thicker yarns. A boat shuttle carries a wound bobbin or quill and can glide quickly across a supported shed. A fly shuttle is propelled across wide cloth by a cord-operated mechanism.

A pick-up stick selects a planned group of warp ends. On a rigid heddle loom, it can hold an additional pattern shed and expand the structures possible beyond basic plain weave.

Common Loom Types in Plain Language

Frame and tapestry looms hold a warp in a fixed frame for hand-controlled weaving. The simplest versions have no moving shedding system. More advanced tapestry looms may add heddle bars, tension controls, or rotating frames that allow the warp to advance.

Inkle looms use a compact open frame, fixed pegs, and string or Texsolv heddles to weave narrow, usually warp-faced bands.

Rigid heddle looms use the slotted-and-holed panel described above. They are portable, quick to dress, and well suited to plain weave and texture. Pick-up sticks, heddle rods, or a second rigid heddle can extend their pattern range.

Table looms are compact shaft looms operated by hand levers, usually on the castle. Each lever controls a shaft, which makes table looms flexible for sampling and complex structures. The weaver changes the lever combination between picks, so the rhythm is more deliberate than treadling a floor loom.

Floor looms use treadles to operate the shafts. Three common systems describe how those shafts move:

• A jack loom raises selected shafts while the others remain in their resting position.
• A counterbalance loom moves shaft groups in opposition. The system is especially comfortable with balanced tie-ups, while some unbalanced structures require adjustments or additional equipment.
• A countermarch loom actively raises some shafts and lowers others, producing a clear shed while keeping both warp layers in motion. Many rug and linen weavers value that shed and the loom's ability to work at firm tension.

Same Part, Different Name

You might read	It may also be called
Heddle	Heald
Shaft	Harness, heald frame
Beater	Batten
Back beam	Whip roll
Breast beam	Front beam, front rest
Sett	Ends per inch, EPI
Reed spacing	Dents per inch, dents per centimeter
Rigid heddle	Rigid heddle reed

Common Questions About Loom Parts

What does a heddle do on a loom?

A heddle controls a warp end. When the shaft or heddle mechanism moves, the heddle moves its warp end and helps open a shed for the weft.

What is the difference between a reed and a rigid heddle?

On a shaft loom, the reed spaces the warp and beats the weft, while individual heddles on shafts control the warp ends. A rigid heddle combines spacing, beating, and basic shedding in one panel.

How many heddles do I need?

Plan for at least one heddle per warp end in the project, then keep extras for future warps and for redistributing heddles across the shafts. Calculate from your weaving width and sett: a 20-inch warp at 20 EPI contains 400 warp ends and therefore needs 400 heddles for an ordinary threading.

What is the difference between sett and dents per inch?

Dents per inch describes the fixed spacing of a reed. Sett describes the number of warp ends you plan per inch of cloth. You can place one or more ends in a dent, or use a repeating sleying sequence, to reach different setts with the same reed.

Do I need a raddle?

A raddle is a standard tool for many back-to-front warping methods because it spreads the warp before beaming. Direct warping on a rigid heddle loom often uses the rigid heddle itself to establish the width. Follow the method recommended for your loom and warping direction.

Are a shaft and a harness the same thing?

In everyday North American weaving, the words are often interchangeable. Some books and manufacturers use harness for the larger lifting assembly, so check the author's terminology when reading older instructions or comparing loom specifications.

Keep This Glossary Beside the Loom

Once shaft, sett, and sley the reed stop sounding like code, patterns become easier to read and equipment becomes easier to evaluate. The names begin to follow the motion: warp unwinds from the back, heddles sort it into groups, the shed opens, the shuttle passes, and the cloth winds forward.

Return whenever a term interrupts your concentration. If you are comparing a new or secondhand weaving loom, knowing the parts by name also helps you see what is present, what is worn, and what the loom still needs before the first warp goes on.