Axial Flux Motor Manufacturers: How to Choose
By Kaan Ozgen · Published
Several companies make axial flux motors, and they sell in three ways: standard catalogue sizes, custom designs, and components such as stators, rotors or frameless kits. Choosing well depends on your stage, your envelope and how you read each datasheet.
This guide lists example suppliers by business model, sets out a comparison method with a worked example, and ends with an RFQ template and the questions that expose differences between datasheets.
Table of contents
- 1. Who Makes Axial Flux Motors
- 2. Three Supplier Types
- 3. Worked Example: Picking a Type
- 4. What to Compare
- 5. Reading a Datasheet: the Three Bases
- 6. A Comparison Table Template
- 7. RFQ Questions for Axial Flux Suppliers
- 8. Where Turncircles Fits
- 9. Common Mistakes When Comparing
- 10. Frequently asked questions
1. Who Makes Axial Flux Motors
Axial flux motors come from a small but growing group of companies with very different business models. The table lists examples of each model, based on what each company publishes on its own site. It is not a ranking and not a complete list; product ranges change, so check each supplier's current offer before you shortlist.
| Company | Based in | What they offer | Model |
|---|---|---|---|
| EMRAX | Slovenia | Catalogue axial flux motors (188 to 348 series); its datasheets note a transition to a next-generation range | Catalogue |
| Allient | USA | SA Series frameless, slotless axial flux kits, from 63.5 mm outer diameter | Component |
| Infinitum | USA | Aircore axial flux motors with printed circuit board stators, for buildings, data centres, industrial and mobility drives | Catalogue and OEM |
| ECM PCB Stator Tech | USA | PCB stator motors and the PrintStator design software | Custom and software |
| YASA | UK | Axial flux traction motors; a Mercedes-Benz subsidiary since 2021 | Automotive OEM |
| Magnax | Belgium | Yokeless axial flux technology, commercialised through market-specific companies | Technology and OEM |
| Turncircles | Czech Republic | Custom coreless axial flux motors with PCB or DCB stators, configured online | Custom |
The list says nothing about which supplier is right for you. That depends on your stage, your envelope and how carefully you read each datasheet, which is what the rest of this guide covers.
2. Three Supplier Types
| Type | What you buy | Good for | Trade-off |
|---|---|---|---|
| Catalogue | Fixed sizes with published datasheets | Quick prototypes, standard envelopes | Limited fit; may be oversized or underpowered for your point |
| Custom | A motor designed around your requirements | Tight envelopes, specific torque, mass or voltage | Longer lead time; a design study is needed |
| Component | Stator, rotor or frameless kit | Teams with their own mechanical and control design | More integration work on your side |
No type is better in general. Match the type to your stage: a catalogue motor can get a prototype running quickly, a custom design takes longer and usually fits better, and a component kit suits teams that want to own the housing and bearings.
3. Worked Example: Picking a Type
A drone team needs 3 Nm continuous at 4,000 rpm, a 90 mm diameter limit and a motor mass under 400 g. First, the power at that point:
P = 3 Nm × (4,000 × 2π ÷ 60) rad/s ≈ 1.26 kW
- A catalogue motor that meets 3 Nm at 4,000 rpm may come in over the diameter or the mass. Check the datasheet on the same torque and mass basis first.
- A custom design can target the 90 mm envelope and the 400 g budget, but needs a design study and a prototype.
- A component kit can meet the envelope if the team designs the housing, bearings and control.
The right choice depends on schedule and in-house skill. If the first prototype is due in a month, start with a catalogue motor that gets close and run a design study in parallel.
4. What to Compare
| Criterion | Why it matters | What to ask |
|---|---|---|
| Continuous torque | Sets the thermal limit | "At what speed and ambient temperature?" |
| Peak torque | Sets acceleration and short-term loads | "For how long, and from what starting temperature?" |
| Mass basis | Decides whether per-kilogram figures are comparable | "Active parts or complete motor?" |
| Data basis | Measured figures include manufacturing effects | "Measured on a test bench, or simulated?" |
| Speed range | Rated torque applies at specific speeds | "Over what speed range?" |
| Cooling | Decides continuous capability | "Natural convection, forced air or liquid?" |
| Environment | Decides where it can be used | "Operating temperature and IP rating?" |
| Lead time | Decides the schedule | "Design study, prototype and series lead times?" |
| Minimum order | Decides the cost of a first build | "Is there a minimum quantity?" |
| Integration | Decides how hard it is to run | "Which controllers and position sensors are supported?" |
| Warranty | Decides what happens when it fails | "What does the warranty cover, and for how long?" |
5. Reading a Datasheet: the Three Bases
Two datasheets can look equal on the front page and be very different underneath. Check three things before comparing:
Torque basis. A rating can be continuous or peak. A peak held for 10 seconds is not comparable with a continuous rating.
Mass basis. A Nm/kg figure is only meaningful once the mass is defined. Active parts (stator and rotor) weigh less than the complete motor with housing, bearings and cover.
Data basis. A simulation shows what the design should do; a test shows what the built motor does, including manufacturing effects. Both are useful, but they are not the same.
Worked example: a motor quoted at 10 Nm per kilogram of active parts, where the housing and bearings make up 40% of the complete motor, delivers:
10 Nm/kg × (1 − 0.40) = 6 Nm/kg of complete motor
The housing share depends on the design, so ask for both figures. The torque and power density guide covers each basis in detail and states the one Turncircles uses.
6. A Comparison Table Template
Ask every supplier for the same rows and fill in the same table. When a supplier leaves a row empty, that tells you something.
| Item | Supplier A | Supplier B | Supplier C |
|---|---|---|---|
| Continuous torque (Nm) at speed (rpm) | |||
| Peak torque (Nm) and duration (s) | |||
| Mass (g), active or complete | |||
| Diameter and length incl. mounting (mm) | |||
| Torque basis | |||
| Mass basis | |||
| Data basis (measured or simulated) | |||
| Cooling method | |||
| Operating temperature and IP rating | |||
| Design study, prototype and series lead time | |||
| Minimum order | |||
| Controller and sensor support | |||
| Warranty |
7. RFQ Questions for Axial Flux Suppliers
- What continuous and peak torque can the motor give, at which speeds and temperatures?
- What is the mass of the complete motor, and what is the mass of the active parts?
- Which figures are measured, and which are simulated? Can I see the test report?
- What cooling does the rating assume?
- What are the axial length and diameter, including mounting?
- Which controllers and encoders has this motor run with?
- What is the lead time for a design study, a prototype and a small series?
- What is the minimum order, and what does the warranty cover?
8. Where Turncircles Fits
Turncircles is a custom supplier. We design coreless axial flux motors around the torque, speed, voltage and envelope you specify, starting in the online configurator, which returns an analytical design and an indicative price before you talk to anyone. We state the basis of every figure and say when a figure is simulated rather than measured. If a catalogue motor already fits your requirement, we will tell you.
Assembly takes as little as 20 working days once the design is fixed; designs with rare-earth magnets can take up to about 50 days because of customs clearance on the magnets. See how a custom electric motor is designed for the full process.
9. Common Mistakes When Comparing
- Comparing a continuous rating with a peak rating.
- Comparing per-kilogram figures with different mass bases.
- Taking a simulated figure as a measured one.
- Ignoring the speed range that the rated torque applies to.
- Forgetting mounting and housing when checking the envelope.
10. Frequently Asked Questions
Who makes axial flux motors?
Examples include EMRAX (catalogue motors), Allient (frameless axial flux kits), Infinitum and ECM PCB Stator Tech (PCB stator motors), YASA and Magnax (automotive and OEM), and Turncircles (custom coreless motors). Check each supplier's current offer, because ranges change.
Should I buy a catalogue motor or a custom one?
Buy a catalogue motor when a standard size fits and you need a prototype fast. Choose a custom design when the envelope, torque, mass or voltage does not fit a standard size.
How do I compare axial flux motors fairly?
Ask every supplier for the same items: continuous and peak torque, mass basis, data basis, cooling, lead time and warranty, and put the answers in one table.
What is the difference between a frameless kit and a motor?
A frameless kit is a stator and rotor without housing, bearings or shaft; the buyer builds those. A motor is a complete unit. Compare masses on the same basis, because a kit weighs much less.
Why do axial flux figures look so different between suppliers?
Usually because of the basis: continuous or peak, active parts or complete motor, measured or simulated. Check all three before comparing.
Is the cheapest motor the best value?
Not necessarily. Compare the cost per unit of torque at the speed you run, with mass, lead time and integration effort included.
Talk to an engineer
Send your torque, speed, voltage and envelope. We will tell you whether a custom axial flux design makes sense, or whether a catalogue motor already fits.
Talk to an engineer