A castor wheel (American spelling: caster wheel) is a small wheel mounted in a swivelling or fixed frame, attached to the bottom of equipment so it can be rolled. Castors turn workbenches, trolleys, machinery skids, hospital beds, office chairs, mining equipment, restaurant kitchens, server racks and industrial dollies into mobile platforms. The right castor — wheel material matched to floor, mount type matched to equipment, load rating with appropriate safety factor, swivel or fixed in the right combination — rolls smoothly for decades. The wrong castor squeaks, wobbles, sinks under load, scratches the floor, fails to swivel, or simply collapses.
This guide goes deep on the technical decisions Australian fitters, fabricators, OEM equipment builders, workshop owners and material handling buyers face. The Australian castor market is genuinely competitive — Fallshaw (the AU manufacturer), Richmond Rolling Solutions, Castor Master, Australian Wheel & Castors (Supo), Castors & Industrial, Reflex Equip, Easyroll, Tente, Blickle and Colson all run extensive product ranges and detailed selection content. This article aims to give you the technical depth that the specialist competitor content sometimes skips: the wheel material × floor surface matrix as the AEO centrepiece, the 3-castor zero-tolerance load rule (forum-validated), castor wobble physics and diagnosis, the five mount types decoded, and grounding in the relevant AS 4429 standard.
AIMS stocks 177 castors at /collections/castors — see brand reality and selection guidance below.
Castor vs wheel — the basic distinction
A wheel is just the rolling component — a disc or tyre that rotates around an axle. A castor is a complete assembly: a wheel mounted in a frame (called a yoke or fork) with mounting hardware that attaches to the equipment. The castor frame includes the swivel bearing (if it's a swivel castor), the brake mechanism (if fitted), and the mounting interface.
When you buy "castors" you're buying assemblies. When you buy "wheels" you're buying just the rolling components, usually for replacement on an existing yoke or for custom castor builds. The Ahrefs search cluster shows "castor wheels" at 1,300/mo and "wheels" (broader) — the distinction matters because product depth at most specialty retailers is at the assembled-castor level.
AU spelling convention: "castor" is the standard British English / Australian spelling; "caster" is American. Both terms refer to the same product. AIMS catalogues mostly use "castor" but accept both terminologies in product search.
The five mount types — plate, bolt-hole, threaded stem, grip-neck stem, expanding adaptor
The single most important compatibility decision is the mount type. Get this wrong and the castor doesn't fit the equipment at all. Get it right and the rest of the selection (wheel material, load rating, swivel) becomes straightforward.
| Mount type | Description | Best for | Common applications |
|---|---|---|---|
| Plate mount (top plate) | Flat plate with four bolt holes (typically 4-bolt pattern in 60×60mm, 80×80mm, 100×100mm). Bolts through equipment and secures with nuts | Workbenches, trolleys, machinery skids, equipment where bolt access is available from inside | The workshop default. Most industrial trolleys and workbenches use plate mount |
| Bolt-hole (centre bolt) | Single bolt hole through the top of the castor, threaded for one machine bolt or through-bolt | Lighter equipment, furniture, where a single fixing is structurally sufficient | Office chairs, light trolleys, kitchen carts, hospital beds. Common in furniture-grade castors (Boori, J.Burrows tier) |
| Threaded stem | Castor with a threaded stud projecting upward from the top of the swivel race. Screws into a threaded receiver in the equipment | Equipment with internal threaded mount points, retrofit installations | Hospital beds, server racks, modular workstations. Stem sizes: M8, M10, M12, M16 metric or 3/8", 1/2" imperial. The "stem castor" forum keyword |
| Grip-neck stem (also "grip neck" or "expanding sleeve stem") | Castor with a stem that has a friction-fit expanding sleeve. Pushes into a tube and locks via the sleeve | Tubular furniture frames, lightweight metal furniture, retail display fixtures | Office chairs, light retail trolleys, IKEA-style assembly furniture |
| Expanding adaptor (round tube) | Castor with an expanding rubber-and-metal adaptor that fits inside round tubing. Tightening a central screw expands the adaptor against tube walls | Tube frames where there's no factory mounting point | Retrofit on existing tube frames, custom equipment builds |
Measure twice. The mount type is determined by what's already in your equipment — you can't choose a mount you don't have a fixing for. For new equipment design, plate mount is the workshop default; for retrofit on existing tubular furniture, expanding adaptor is often the only practical option.
Swivel vs fixed vs braked — castor configuration
The four standard castor configurations and when each applies:
- Swivel castor (rigid) — wheel rotates around its axle and the entire yoke rotates around a vertical swivel axis. Allows the equipment to be pushed in any direction. The workshop default for trolleys and mobile workbenches.
- Fixed castor (rigid) — wheel rotates around its axle but the yoke does not swivel. Forces equipment to travel in a straight line in the direction the castor faces. Used in pairs with swivel castors for directional control (typical configuration: 2 fixed at rear, 2 swivel at front).
- Braked castor (swivel + brake) — swivel castor with a foot-operated brake. The brake either locks the wheel only (called "wheel lock" or "side brake") or locks both wheel and swivel ("total lock" or "directional lock"). Workshop trolleys, hospital beds and any equipment that needs to stay put when parked.
- Total lock castor — premium braked castor that locks both wheel rotation AND swivel motion simultaneously. Equipment can't roll AND can't yaw under impact load. Standard on medical equipment, server racks and equipment that absolutely must stay put.
The classic 4-castor configuration for a trolley or workbench: 2 swivel castors at the front (often braked), 2 fixed castors at the rear. Forum reality from r/BeginnerWoodWorking: "100mm castor wheels with the push down brake with a capacity of 125kg" — push-down brake on swivel castors is the workshop default for mobile workbenches.
For equipment that must move sideways as well as forward (set design, theatre, film production), triple-swivel castors exist — they change direction instantly without the "first shove" needed to align standard swivels. Facebook Set Designers community discussion: "Triple Swivel casters will change direction instantly... No need to have the first shove to..."
Wheel material — the workshop selection decision
The wheel material determines what surface the castor rolls on, how heavy a load it carries, how quiet it runs, how it resists workshop chemicals, and how long it lasts. Eight standard wheel materials cover almost all applications.
| Wheel material | Properties | Best for | Avoid in |
|---|---|---|---|
| Polyurethane (PU) on cast iron core | Hard PU tyre bonded to cast iron centre. High load capacity, low rolling resistance, oil/grease/chemical resistant, doesn't mark floors | Workshop concrete, smooth shop floors, heavy duty applications. The workshop default for trade use | Rough/uneven surfaces (no shock absorption), very low temperatures (PU stiffens) |
| Polyurethane (PU) on nylon core | Hard PU tyre on nylon centre. Lighter weight, lower load than cast iron core, still oil/chemical resistant | Medium duty mobile equipment, light trolleys, workshop carts | Heavy duty over 300kg per castor (use cast iron core variant) |
| Solid rubber | Soft, quiet rolling, good shock absorption, low traction loss on uneven floors | Office environments, hospitals (noise), light industrial, equipment that crosses door thresholds | Workshop concrete with oil/grease (rubber degrades), heavy loads (rubber compresses), chemicals |
| Pneumatic (air-filled rubber) | Pneumatic tyre on metal rim. Excellent shock absorption, low rolling resistance on rough surfaces, gentle on payload | Gravel, asphalt, outdoor applications, rough construction sites, agricultural use. r/Workbenches gravel-driveway use case | Heavy industrial fixed installations (puncture risk), high-load applications |
| Phenolic resin | Hard resin-bonded wheel. High load capacity, low rolling resistance, doesn't crack like cast iron | Industrial floors, heavy machinery, hot dry environments | Wet floors (can delaminate), rough surfaces (no shock absorption) |
| Cast iron | Solid iron wheel. Very high load capacity, highest impact resistance, doesn't deform under sustained load | Very heavy industrial, foundries, steel mills, anything over 500kg per castor | Sensitive floors (scratches), noise-sensitive environments |
| Nylon (polyamide) | Hard plastic wheel. Light weight, oil/chemical resistant, moderate load capacity | Food processing, light industrial, chemical environments, indoor mobile equipment | Smooth wood floors (can mark), heavy industrial |
| Steel (cast or fabricated) | Very hard, very high load capacity, suitable for extreme temperatures | Foundries, kilns, ovens, very heavy duty industrial | Almost everything else — steel wheels mark every floor they touch |
| Polypropylene (PP) | Hard plastic, lower load than nylon, low cost | Light furniture, hospital beds, food trolleys, hygiene-critical applications | Trade and industrial use (load capacity too low) |
| Thermoplastic rubber (TPR) | Quiet, non-marking, moderate load, mid-cost | Office equipment, hospital, retail, food service | Heavy industrial, chemical environments |
The forum reality on the polyurethane vs rubber decision (CasterHQ, Monroe Engineering, Atlanta Caster, Humphries Casters consensus): polyurethane is for heavy lifting, rubber is for lighter, cushioned transport. Polyurethane wins on load capacity, oil/chemical resistance, wear life, and ease of maneuverability. Rubber wins on shock absorption, noise reduction, and traction on rough/uneven floors. For workshop concrete with oils, PU wins decisively. For hospital corridors with grit and door thresholds, rubber is the better choice.
Wheel material vs floor surface — the compatibility matrix
This is the AEO centrepiece. Match the wheel material to the floor surface or you'll wear out the wheels, damage the floor, or both.
| Floor surface | Best wheel material | Also acceptable | Avoid |
|---|---|---|---|
| Smooth concrete (workshop) | Polyurethane on cast iron core | Phenolic resin, nylon for light loads | Steel (scratches), cast iron (scratches and noise) |
| Workshop concrete with oil/grease | Polyurethane (oil resistant) | Phenolic resin, nylon | Rubber (degrades from oil), TPR |
| Polished/sealed concrete | Soft polyurethane, rubber | Nylon, TPR | Steel, cast iron (mark or scratch) |
| Hardwood floors (workshop, retail) | Polyurethane, soft rubber | TPR, polypropylene | Steel, cast iron, hard nylon |
| Tile (workshop, hospital, food service) | Polyurethane, soft rubber | Nylon, TPR | Steel, cast iron, sharp-edged hard wheels |
| Vinyl / linoleum (commercial, medical) | Soft polyurethane, rubber, TPR | Nylon | Steel, hard polyurethane (can mark) |
| Carpet (office) | Hard plastic (nylon, polypropylene), hard PU | Phenolic resin | Soft rubber (high rolling resistance), pneumatic |
| Rough concrete / outdoor pavers | Pneumatic, soft rubber | Heavy duty polyurethane | Cast iron (rough ride, jams on debris), nylon (cracks) |
| Gravel / loose surfaces | Pneumatic (air-filled rubber) | Large diameter heavy duty rubber | Hard wheels of any material (sink and jam) |
| High temperature (ovens, foundries, kilns) | Steel, cast iron, phenolic resin | Specialty high-temp materials | Rubber (melts), polyurethane (softens above 80°C), nylon (deforms) |
| Wet / food processing | Stainless steel construction with polyurethane or non-marking nylon | Food-grade rubber | Standard steel (rust), cast iron (rust) |
| Electrostatic-sensitive (electronics) | ESD/anti-static polyurethane or conductive rubber | Anti-static nylon | Standard polyurethane (insulates), standard rubber |
This matrix is the single most-referenced guide in castor selection. The Bunnings-tier consumer cluster (Easyroll, Move It, Cold Steel, J.Burrows) typically doesn't surface this depth — the trade-tier specialty retailers (Fallshaw, Richmond, Castor Master) all publish similar matrices.
Load rating — and the 3-castor zero-tolerance rule
The most-misunderstood specification in castor buying. Load rating is per castor, and on a 4-castor assembly, you cannot simply multiply by 4 to get total capacity.
Why the math doesn't multiply linearly
The forum-validated explanation comes from r/AskEngineers ("If I want to support 2000lbs, will 4 casters rated at 500lbs work?"): "Theoretically, four 500 lbs casters would work. But I wouldn't advise a zero tolerance..." The reason is floor flatness. On a perfectly flat floor with a perfectly rigid frame, 4 castors share the load equally — 2,000 lbs ÷ 4 = 500 lbs per castor, exactly at the rating limit, no safety factor. In the real world, no floor is perfectly flat, and no frame is perfectly rigid.
At any given moment on an uneven floor, the equipment rocks slightly and only 3 castors are taking the load. The fourth is momentarily off the ground. The 3-castor rule is the workshop reality: divide your total load by 3, not 4, then add a safety factor of 25-50%.
The 3-castor rule applied — worked example
You have a 1,000 kg machine on 4 castors. The math:
- Total load = 1,000 kg
- 3-castor distribution = 1,000 ÷ 3 = 333 kg per castor (worst case)
- Safety factor 30% = 333 × 1.3 = 433 kg per castor
- Minimum castor rating = 450 kg per castor (round up to next available rating)
The 4-castor naive calculation would say 250 kg per castor. The 3-castor real-world rule says 450 kg per castor. Big difference, and the difference is exactly why workshops with under-rated castors see them fail.
Static vs dynamic load rating
Most castor manufacturers publish static load rating — what the castor holds while stationary. Dynamic load rating (the load the castor handles while rolling) is typically 60-75% of static rating. Manual movement is typically rated at static; powered equipment (electric tugs, AGVs) is rated dynamically because of higher impact loads.
For heavy industrial loads, also check the impact load rating — what the castor survives during a momentary shock load (going over a threshold, hitting an obstacle, being dropped during installation). Premium brands (Fallshaw X-series, Tente, Blickle) publish impact ratings; budget castors typically don't.
Bearing types — ball, roller, plain, precision
The bearing in the wheel and the bearing in the swivel race determine how smoothly the castor rolls and swivels — and how long it lasts. Quality castors use real bearings; cheap castors use a plain bushing.
The forum-validated quality differentiator from r/Tools direct: "Casters with real bearings instead of just a bolt and a bushing will be very very smooth, ones with bushings will be hit and miss..." If you're buying castors for daily use, sealed ball bearings are worth the premium.
| Bearing type | Properties | Best for |
|---|---|---|
| Sleeve bearing (plain bushing) | Just a bolt rotating in a hole, sometimes with a nylon sleeve. Cheap, simple, high friction | Light occasional use, furniture, low-cost castors |
| Roller bearing | Cylindrical rollers reduce friction in the wheel. Higher load capacity, lower rolling resistance | Medium duty, mobile workshop equipment |
| Ball bearing (single race) | Caged ball bearing. Low rolling friction, moderate load, longer life | Premium workshop, light industrial, office equipment |
| Ball bearing (double race / sealed) | Two sealed ball bearing races. Excellent load capacity, very low friction, longest life. Resists ingress of debris | Heavy industrial, high-duty cycle, harsh environments |
| Tapered roller bearing | Conical roller bearing. Highest load capacity including side loads | Very heavy industrial castors, equipment with sustained side loads |
| Precision bearing | Manufacturer-spec'd precision sealed bearings | Medical equipment, laboratory equipment, specialty applications where rolling friction must be predictable |
Swivel race bearings follow the same hierarchy. Premium castors have hardened raceways and either ball bearings or roller bearings in the swivel — this is what makes a quality castor swivel under load. Cheap castors with plain washer bearings under the swivel race start binding under load and won't swivel at all when fully loaded.
Castor wobble — the diagnosis and fix
The single most-reported castor problem on Reddit and workshop forums is wobble at speed. r/wheelchairs across multiple threads, r/wheelchairs FAQ: "If your wheels are in good alignment and you still get the shaking, it is probably castor wobble. The smaller the front wheels (castors), the more wobble."
What causes wobble
Wobble is a self-reinforcing oscillation of the castor around its swivel axis. As the equipment moves forward, the castor wheel encounters small imperfections that deflect it slightly. The swivel geometry tries to self-align. If the offset/trail isn't right, the deflection oscillates instead of damping — and you get a high-frequency shimmy that gets worse as speed increases.
Four causes documented across forums:
- Castor diameter too small for the speed — smaller castors have less angular momentum and wobble at lower speeds. Larger castors (150mm+) wobble less. r/wheelchairs consensus: "The smaller the front wheels (castors), the more wobble."
- Swivel race worn or contaminated — friction in the swivel bearing damps oscillation. Worn bearings can swivel too freely, exacerbating wobble
- Trail/offset geometry wrong — castor with insufficient offset (the distance from the swivel axis to the wheel axle) self-aligns poorly. Premium castors have engineered offset for stability
- Load imbalance — uneven weight distribution makes some castors run heavier than others, contributing to oscillation
Fixing wobble
Diagnostic order:
- Inspect bearing condition — grit, rust, free play in the swivel race
- Check tightness — over-tightened swivel bearing binds; under-tightened wobbles. Should swivel freely without play
- Check wheel alignment — wheel axle should be parallel to floor, fork should be plumb vertical
- Step up wheel diameter — 75mm → 100mm → 125mm. Larger castors damp wobble
- Replace with quality castors with engineered offset (Fallshaw, Tente, Blickle, Richmond range) if budget castors are the source
- For mobile bench applications, add a brake to lock swivel during work — eliminates wobble during operation
Castor wheel diameter — 50mm to 200mm+
Wheel diameter is a key spec. Larger diameter = lower rolling resistance, easier obstacle clearance, less wobble; smaller diameter = lower castor height (lower equipment), less material cost.
| Diameter | Typical load per castor | Best for |
|---|---|---|
| 50mm (2") | 30-50 kg | Office chairs, light furniture, small carts |
| 75mm (3") | 50-100 kg | Medium furniture, light trolleys, retail fixtures |
| 100mm (4") | 100-150 kg | Workshop trolleys, mobile workbenches, hospital beds, the trade workshop default. r/BeginnerWoodWorking: "100mm castor wheels with the push down brake with a capacity of 125kg" is the standard mobile workbench spec |
| 125mm (5") | 150-250 kg | Heavy duty workshop, light industrial trolleys, mobile workstations with equipment |
| 150mm (6") | 250-400 kg | Heavy industrial trolleys, mobile machinery, foundry trolleys |
| 200mm (8") | 400-800 kg | Very heavy industrial, mobile generators, large dollies |
| 250mm-300mm | 800-1500 kg+ | Heavy industrial, mobile machinery, mining equipment |
Obstacle clearance rule of thumb: castor wheel rolls over an obstacle up to about 1/3 of wheel diameter without significant force. A 75mm wheel hits the wall at 25mm obstacles (cables, door thresholds); a 150mm wheel rolls over 50mm obstacles smoothly. For workshop floors with cable runs or any threshold work, 125mm-150mm is the sweet spot.
Heavy duty castor — what defines it
"Heavy duty castor" is a marketing term that means different things at different price points. The Bunnings/Easyroll heavy duty range typically tops out around 200-250 kg per castor. Trade-tier heavy duty (Fallshaw X-series, Tente VPA-VVPA, Blickle GTH-GSPO, Richmond heavy duty range) starts at 500 kg per castor and goes to 3,500+ kg.
What makes a castor genuinely heavy duty:
- Cast iron yoke (not pressed steel) — pressed steel yokes deform under heavy impact loads. Cast iron yokes survive abuse
- PU-on-cast-iron wheel construction — polyurethane tyre bonded to a cast iron centre. Combines load capacity (cast iron) with floor-friendly contact (PU). Fallshaw X-series uses this construction
- Sealed double-ball-bearing swivel race — survives debris and load. Plain washer bearings fail fast under heavy load
- Kingpinless construction — the swivel mechanism integrated into the yoke rather than a separate kingpin bolt. Kingpinless eliminates the single point of failure (kingpin shearing under impact) that destroys budget heavy duty castors
- Tapered roller bearings in the wheel — handle radial and thrust loads simultaneously
- AS 4429 compliance — the AU standard for industrial castors
Fallshaw's X Series specification (the AU manufacturer's heavy duty range): "Very heavy duty cast iron castors. 100mm, 125mm, 150mm and 200mm diameter wheels, Load rating: 600–1000 kg." Compare to Easyroll 100mm Heavy Duty Swivel Brake at 150 kg — both labelled "heavy duty," but in different leagues entirely.
Specialty castors — ESD, high-temp, food-grade, leveling, suspension
Beyond the standard catalogue, several specialty castor classes exist for specific applications:
- ESD / anti-static castors — electrically conductive polyurethane or rubber wheels with conductive yokes. Discharge static through the equipment to the floor. Standard for electronics workshops, semiconductor fabs, and any equipment handling sensitive components. AS/IEC 61340 ESD compliance
- Food grade castors — stainless steel construction with non-marking polyurethane or polypropylene wheels. Compliant with AS/NZS food contact regulations. Standard for food processing, commercial kitchens, pharmaceutical, beverage manufacture
- High temperature castors — phenolic, steel, or specialty high-temp polyurethane. Resist 150°C, 200°C and higher. Used at oven exit conveyors, foundry trolleys, kiln carts
- Leveling castors / glides — combination castor with a screw-down foot. Roll into position, then lower the foot to lift the wheel and create a fixed leg. Server racks, large equipment, machine tools. VEVOR Leveling Casters at Bunnings are the consumer tier; Fallshaw, Tente and Blickle make the industrial tier
- Total-lock castors — single foot pedal locks both wheel and swivel. Medical equipment standard. Premium specification, premium price
- Suspension castors / spring-loaded — castor with internal spring suspension. Absorbs impact loads. Standard for heavy mobile equipment over uneven floors. r/AskEngineers: "There are spring loaded (suspension) casters and..." — the heavy-load uneven-floor solution
- Hospital castors — twin-wheel construction, quiet polyurethane or TPR, easy-clean, total-lock options. Class-1 medical-grade compliance
- Pneumatic castors — air-filled rubber tyres for outdoor and rough-terrain use. r/Workbenches direct: "I'd like to have the ability to roll my workbench out of my garage onto my gravel driveway... air filled rubber wheels would be appropriate here. Maybe something like a lazy..."
Swivel geometry — offset, trail and pushability
The geometry of a swivel castor — specifically the offset between the swivel axis and the wheel axle — determines how easily the castor self-aligns and how stable it runs at speed. This is the engineering parameter that separates well-designed castors from poorly-designed ones.
Offset is the horizontal distance from the vertical swivel axis to the wheel axle. Larger offset = better self-alignment, smoother swivel under load. Small offset = harder to push, more wobble, swivel binds under load.
Premium AU manufacturers (Fallshaw, Tente, Blickle) publish offset specifications. Most workshop castors don't — the offset is "good enough" for the load class but not engineered. When evaluating high-volume mobile equipment, offset matters: it determines whether your trolleys glide or fight.
The "shopping trolley wobble" you experience at the supermarket is castor wobble from undersized castors with insufficient offset, loaded beyond the design intent. Quality industrial trolleys with engineered castor geometry don't wobble at any speed.
Brake types — wheel lock, total lock, directional lock
Three brake mechanisms cover most applications:
- Wheel lock (side brake) — foot-operated lever locks the wheel from rotating. The castor can still swivel, so the equipment can be wheeled sideways or rotated when stationary. The basic brake for most trolleys
- Total lock (combined brake) — single foot pedal locks BOTH the wheel and the swivel simultaneously. Equipment is genuinely parked. Standard for medical equipment, server racks, and any equipment that absolutely must stay put under impact load
- Directional lock — castor locks the swivel only, allowing the wheel to roll but only in a fixed direction. Useful for long straight pushes where the equipment shouldn't wander
The premium castor brake is the total lock pedal foot brake — a single foot pedal that operates both wheel and swivel lock. Standard on premium medical, laboratory and server rack castors.
Common castor mistakes — forum-validated diagnostic table
| Mistake | What goes wrong | Fix |
|---|---|---|
| Castor capacity calculated as load ÷ 4 | On uneven floors only 3 castors share load. 4-castor naive math under-rates by ~30% | Apply the 3-castor rule: total load ÷ 3, then add 30% safety factor. r/AskEngineers forum-validated |
| Cheap castors with plain bushings | Hit-and-miss rolling, swivel binds under load, fails in months | r/Tools: "Casters with real bearings instead of just a bolt and a bushing will be very very smooth" — invest in sealed ball bearings for daily use |
| Wrong wheel material for the floor | Steel on hardwood = scratches; rubber on oily concrete = degrades; cast iron on polished concrete = marks | Use the wheel material × floor matrix above. Polyurethane on cast iron core is the workshop default for concrete |
| Castor wobble ignored | Builds up at speed, makes equipment unusable, accelerates bearing wear | Step up castor diameter (more angular momentum damps wobble), check bearing condition, verify trail/offset geometry |
| Plate mount holes don't match | Castor doesn't fit equipment, requires drilling new holes | Measure plate dimensions and bolt pattern (60×60, 80×80, 100×100mm) before ordering. Standard 4-bolt patterns dominate but not universal |
| Wrong stem thread size | Threaded stem doesn't fit equipment receiver — won't tighten or strips threads | Verify stem size (M8, M10, M12, M16, or imperial 3/8", 1/2"). When in doubt, plate mount is more flexible |
| Heavy duty without kingpinless construction | Standard kingpin bolt shears under impact load, swivel fails completely | For loads above 300 kg per castor, specify kingpinless construction (Fallshaw X-series, Tente, Blickle) |
| Brake on wrong castor | Wheel-lock brake on a swivel that still rotates lets equipment roll around the locked wheel | For equipment that must stay put, use total-lock castors on at least 2 of 4 wheels |
| Castor "won't swivel" | Rust, debris, over-tightened swivel screw, bearings collapsed | r/OfficeChairs + r/wheelchairs: disassemble, clean, regrease, replace if bearings shot. For repeat issues, sealed bearings prevent debris ingress |
AS 4429 and the Australian castor market
AS 4429 is the Australian Standard for industrial castors and wheels — specifying test methods, performance categories, dimensions, marking requirements, and safety criteria. Premium AU castor brands (Fallshaw, Richmond, Castor Master) publish AS 4429 compliance prominently. European brands often cite EN 12527-12533 (the equivalent European standard).
The Australian castor market is genuinely competitive — multiple specialist suppliers run extensive product ranges:
| Brand / supplier | Position | Range | Notes |
|---|---|---|---|
| Fallshaw Wheels & Castors | AU manufacturer, premium | 30 kg light duty to 3,500 kg very heavy duty. Polyurethane, stainless, pneumatic, specialised, decorative. X-series very heavy duty cast iron | The AU industry reference. Manufactured locally. Industry consensus premium tier |
| Richmond Rolling Solutions (Sydney NSW) | AU industrial supply | Rigid, swivel, directional lock, lockable. Up to 500 kg heavy duty | Caringbah NSW operation. Major industrial supplier |
| Castor Master | Pure-play castor specialist | Wide AU-wide delivery, 300 kg+ heavy duty focus | Online specialist |
| CastorCo | Online castor specialist | Volume sets and free-freight thresholds on bulk orders | Volume-pricing online |
| Australian Wheel & Castors (Supo Castors) | Big-range specialist | 3,000+ products across light to extra heavy duty. Urethane on cast iron focus | Comprehensive product depth |
| Castors & Industrial | 30-year specialist | Castors, wheels, materials handling, hardware | Long-established AU specialist |
| Reflex Equip | Heavy duty specialist | 450 kg to 3,500 kg capacity | Extra-heavy industrial focus |
| Tente | German global premium | Full range across all sectors. Premium tier | Medical and industrial premium |
| Blickle | German global premium | Heavy duty specialty including nylon/compressed cast nylon impact-resistant series | European trade-tier reference |
| Colson | US global | Wide industrial range | US industry standard |
| Easyroll | AU brand at Bunnings | Mid-tier heavy duty, swivel, brake variants | Bunnings consumer-trade crossover |
| Move It (Bunnings own-brand) | Bunnings consumer tier | Light to medium duty workshop and home use | Consumer/light trade |
| Cold Steel (Mitre 10) | Consumer hardware | Furniture and light workshop castors | Mitre 10 channel |
| J.Burrows (Officeworks) | Office furniture | Office chair and light furniture replacement | Officeworks channel |
| ToolPRO (Supercheap) | Auto/workshop consumer | Light to medium workshop trolley castors | Supercheap Auto channel |
| VEVOR | Online consumer | Budget heavy duty and leveling castors via Amazon | Quality variance, online retail tier |
AIMS positioning honest scope: AIMS plays the industrial trade tier with 177 SKUs across mixed brands at /collections/castors. AIMS doesn't carry the depth of pure-play specialists like Fallshaw (full local-manufacture range) or Richmond (3,000+ products) — those are specialty distributor relationships. AIMS provides solid mid-market industrial castor coverage for general trade use; for highly specific heavy-duty applications, the specialist channels are the right call.
AIMS castor range
AIMS stocks 177 castors across the standard categories at /collections/castors, with additional wheel-only inventory in /collections/wheels (46 SKUs).
Categories covered in AIMS supply: plate-mount and bolt-hole mount castors in M8/M10/M12 stem sizes, swivel and fixed configurations, swivel-with-brake variants, polyurethane on cast iron and polyurethane on nylon wheel constructions, rubber wheel options for light duty and noise-sensitive applications, heavy duty industrial castors with sealed bearings, and replacement wheel inventory.
For specialty requirements — Fallshaw X-series very heavy duty, Tente premium medical, Blickle impact-resistant nylon, ESD/anti-static specialty, food-grade stainless — contact the relevant specialist distributor (Fallshaw direct, Richmond Rolling Solutions for Sydney NSW industrial, Castor Master for online specialty). For high-volume orders or specific brand requirements not in the AIMS stock range, call (02) 9773 0122 or visit contact us — we can source through the supplier network.
Adjacent guides: Pallet Jack Guide (manual material handling alternative for pallet-load work), Storage Bins Guide (workshop organisation), Drum Handling Equipment Guide (drum-specific material handling), Safety Boots Guide (workshop PPE).
Frequently Asked Questions
What's the difference between a castor and a caster?
None. Castor is the British English / Australian spelling; caster is American English. Both terms refer to the same product — a wheel mounted in a swivelling or fixed frame attached to the bottom of equipment so it can be rolled. AU catalogues mostly use "castor" but accept both terminologies in product search. The Ahrefs cluster shows AU searches for both spellings with similar volumes.
Polyurethane vs rubber castor wheels — which is better?
Depends on the application. Polyurethane is for heavy lifting, lower noise, oil/chemical resistance, and easier maneuverability on smooth floors — the workshop default. Rubber is for lighter loads with cushioned transport, shock absorption, traction on rough surfaces, and quieter rolling. CasterHQ and Caster City consensus: polyurethane wins on load capacity (3-5× higher), wear life, and chemical resistance. Rubber wins on shock absorption and traction. For workshop concrete with oils, polyurethane wins decisively. For hospital corridors or noise-sensitive office, rubber is the better choice.
How do I calculate the load rating I need?
Use the 3-castor rule. On uneven floors, only 3 of 4 castors share the load at any moment. Calculation: (total load) ÷ 3, then add 30% safety factor. Example: 1,000 kg equipment ÷ 3 = 333 kg per castor; × 1.3 safety = 433 kg per castor; round up to next available rating. The naive 4-castor math (load ÷ 4) under-rates by ~30% on uneven floors. r/AskEngineers forum-validated: "Theoretically, four 500 lbs casters would work. But I wouldn't advise a zero tolerance."
What size castor wheel do I need?
Diameter depends on load and floor conditions. 50-75mm for office/furniture; 100mm for workshop trolleys (the workshop default — 100-150 kg per castor); 125mm for heavy workshop; 150mm for heavy industrial; 200mm+ for very heavy duty. Obstacle clearance rule: castor rolls over obstacles up to about 1/3 of wheel diameter. A 75mm wheel hits the wall at 25mm thresholds; a 150mm wheel handles 50mm obstacles smoothly. For workshops with cable runs, 125mm-150mm is the sweet spot.
Why does my castor wobble at speed?
Castor wobble is a self-reinforcing oscillation around the swivel axis. Four common causes: castor diameter too small (smaller castors wobble at lower speeds — r/wheelchairs: "The smaller the front wheels, the more wobble"); swivel race worn or contaminated; trail/offset geometry inadequate (cheap castors with poor offset wobble more); load imbalance. Fix: inspect bearings, check tightness, verify wheel alignment, step up wheel diameter (100mm → 125mm → 150mm), or replace with engineered-offset premium castors (Fallshaw, Tente, Blickle).
What's a kingpinless castor?
A castor design where the swivel mechanism is integrated into the yoke rather than relying on a separate kingpin bolt. Kingpinless construction eliminates the single point of failure (the kingpin shearing under impact load) that destroys budget heavy duty castors. Standard on premium heavy duty (Fallshaw X-series, Tente, Blickle). For loads above 300 kg per castor or any application with shock loading, kingpinless is the right specification.
What's the difference between a wheel lock brake and total lock?
A wheel lock brake (also called side brake) locks the wheel from rotating but the castor can still swivel — equipment can be rotated or pushed sideways when stationary. A total lock brake locks BOTH the wheel and the swivel via a single foot pedal — equipment is genuinely parked and can't move or yaw under impact. Total lock is standard for medical equipment, server racks, and any application where the equipment must stay put under load. Wheel lock is the basic brake for most workshop trolleys.
What mount type should I use?
Plate mount is the workshop default — flat plate with 4 bolt holes (60×60mm, 80×80mm, 100×100mm patterns are common). Use when you have or can drill 4 bolt fixings in the equipment. Bolt-hole (centre bolt) is for lighter equipment with a single fixing. Threaded stem (M8/M10/M12/M16) is for equipment with internal threaded receivers — common on hospital beds and server racks. Grip-neck stem is for tubular furniture frames. Expanding adaptor fits inside round tube where there's no factory mounting. Measure the equipment before ordering — the mount type is determined by what's already there.
Why won't my castor swivel?
Most common causes: bearing seized due to rust or contamination, screw over-torqued (binds the swivel race), debris ingress in the swivel mechanism, fork not square to the floor (forces sideways binding), or bearings collapsed entirely. r/OfficeChairs + r/wheelchairs documented across many threads. Fix: disassemble, clean, regrease, replace if bearings are shot. For repeat issues in dirty environments, specify sealed bearings — they prevent the debris ingress that causes most failures.
Do I need castors with brakes?
Depends on use. For workshop trolleys that need to stay put while you work on equipment loaded on them — yes, brakes are essential. Standard configuration: 2 swivel-with-brake castors at the front, 2 fixed at the rear. For shopping trolleys, rolling stock that moves continuously without stopping — no brakes needed. For medical equipment that must absolutely stay put under patient movement — total-lock castors on at least 2 of 4 wheels. Forum reality from r/BeginnerWoodWorking: "100mm castor wheels with push down brake" is the workshop mobile workbench default.
Can I use castors on a gravel driveway or outdoors?
Yes, with the right wheel material. Pneumatic (air-filled rubber) castors are designed for gravel, asphalt, rough concrete, and outdoor conditions. They absorb shock and roll over loose surfaces that solid wheels jam against. r/Workbenches direct: "I'd like to have the ability to roll my workbench out of my garage onto my gravel driveway. Does anyone have any suggestions on heavy duty casters... air filled rubber wheels would be appropriate here." For permanent outdoor use, pneumatic with sealed bearings to resist moisture.
What's the difference between static and dynamic load rating?
Static load rating is what the castor holds while stationary — the published headline rating from most manufacturers. Dynamic load rating is what the castor handles while rolling, typically 60-75% of static rating because rolling loads include impact and shock components. Manual movement is usually rated at static; powered equipment (electric tugs, AGVs) is rated dynamically. Premium brands (Fallshaw, Tente, Blickle) also publish impact load rating — what the castor survives during a momentary shock load.
Will hard castors damage my floor?
Material matters. Cast iron and steel wheels mark or scratch almost every floor they touch. Hard polyurethane on smooth concrete generally doesn't mark. Soft rubber on hardwood is usually safe but can leave marks if dirty (grit caught between wheel and floor). For sensitive floors (sealed concrete, polished concrete, hardwood) use soft polyurethane or non-marking TPR. For carpet, hard plastic (nylon, polypropylene) rolls easier with lower resistance. The forum reality from r/OfficeChairs: "If the wheels are clean (no grit on the floor) then the rubber wheels will be gentler" — keep castors clean to protect floor finish.
How do I retrofit castors on existing furniture?
Three approaches depending on the furniture construction. (1) If the furniture has solid legs you can drill, use plate mount castors with 4 bolts through a steel plate fixed under the leg. (2) If the furniture has tubular legs (typical office furniture), use expanding adaptor castors — they fit inside the tube and expand to grip. (3) If the furniture has threaded receivers (common on retail and modular furniture), use threaded stem castors in the matching size. For older furniture without any mounting, plate mount is most flexible — make a steel adapter plate that bolts to the existing furniture base.
What does AS 4429 cover?
AS 4429 is the Australian Standard for industrial castors and wheels. It specifies test methods, performance categories, dimensions, marking requirements, and safety criteria for castors used in industrial material handling. Premium AU castor brands (Fallshaw, Richmond Rolling Solutions, Castor Master) publish AS 4429 compliance prominently in product listings. European brands often cite EN 12527-12533 (the equivalent European standard family). For industrial procurement and Safe Work Australia compliance contexts, AS 4429 marking is the trade-tier benchmark.
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