Custom Electric Motors: What They Are, What They Cost, How to Order One
By the Turncircles engineering team · Published
A custom electric motor is a motor designed around your application instead of the other way round. That sounds obvious, and yet most "custom" motors are catalogue motors that learned a new shaft. This guide explains what real customisation involves, who benefits from it, what it costs and how long it takes. We design and build custom axial flux motors, so we will also tell you when you do not need one.
We publish prices, lead times and limits, because "contact sales for a quote" is a poor way to start a relationship. You will find the numbers below, and the live estimator on the pricing page.
Configure your motor See custom electric motor pricing
What "Custom Electric Motor" Actually Means
The phrase covers a surprisingly wide range, and suppliers use it generously. A motor with your logo on the nameplate is not custom. A motor with a longer shaft is, strictly, customised, but only in the way a pizza with extra cheese is a custom recipe. It helps to see the whole spectrum:
| Level | What changes | Typical result |
|---|---|---|
| Catalogue motor | Nothing. You pick a model from a datasheet. | Your application adapts to the motor: gearbox, oversizing, mismatched voltage. |
| Modified standard motor | Shaft, connector, cable length, winding variant. | Better fit at the interface, same compromise inside. |
| Custom electric motor | Winding, magnets, air gap, diameter, stack count, stator, housing, protection. | The motor adapts to your application. Torque, speed and voltage are inputs, not constraints. |
Everything on this page is about the third row: a motor whose electromagnetic design is made for one application. That is the difference that shows up as efficiency, weight and lifetime, and the reason we wrote how a custom motor is designed and why efficiency is decided at application level.
Who Needs a Custom Electric Motor (and Who Does Not)
Honesty first, because it saves us both a call. If a standard motor from a catalogue does your job at the volume you need, buy it. It will be cheaper, it will be on a shelf, and nobody will ask you to fill in a torque requirement. A custom motor earns its keep when one of these is true:
- Weight or size is a hard limit. Drones, aircraft, robots, wheelchairs and anything else that carries its own motor around. See lightweight axial flux motors.
- The catalogue needs a gearbox you would rather not have. A motor designed for the speed and torque of the load can often drive it directly, which removes the gearbox, its losses and its noise.
- Efficiency is money. Motors running many hours a year turn small efficiency gains into real energy savings.
- The envelope is odd. A flat disc where a cylinder will not fit, a hollow centre for a shaft or a cable, a motor that has to live inside a wheel rim.
- You are building a product, not a prototype. The motor is part of what you sell, and you want to control its performance, lifetime and supply.
If none of these ring a bell, we will say so. We would rather lose a quote than build you the wrong motor.
Custom DC, Brushless and AC Motors: Which Type Do You Need?
Customers often search for "custom DC motors", "custom brushless DC motor" and "custom AC motors" as if they were three different shopping aisles. Mostly they are one aisle with confusing signs. Turncircles builds permanent magnet brushless motors in axial flux form. They run from a DC supply, up to 370 VDC, through an electronic drive that feeds the three motor phases. Inside the machine, those phase currents are alternating, which is why the same motor is called a BLDC motor by one engineer and a permanent magnet synchronous motor by another.
What we do not build: brushed DC motors and mains-driven induction motors. If that is what you need, a catalogue is the right place. The full picture, including a plain-language table of motor types, is on the custom brushless DC motors page.
What Gets Customised in a Turncircles Motor
Everything that decides how the motor behaves is a parameter in one parametric model, which is why you can see a first result in minutes, not after months of engineering:
- Outer diameter from 60 mm to 406 mm, because torque grows with the cube of the radius in an axial flux design.
- Stack count. Stacks add torque and power without adding footprint, so you scale by thickness instead of diameter.
- Winding and voltage. Turns and conductor geometry set the torque constant and the speed at your supply voltage, up to 370 VDC.
- Magnets and air gap. Grade, thickness and gap set the flux that reaches the winding. See the magnet selector.
- Stator technology. Printed PCB or DCB stators instead of wound copper and iron, see PCB and DCB stators.
- Housing and protection. Housed, naked or wet, with protection up to IP67.
| Parameter | Range (maximum values, not one motor) |
|---|---|
| Outer diameter | 60 to 406 mm |
| Nominal torque | Up to 24 Nm per stack, up to 100 Nm multi-stack |
| Nominal speed | Up to 6,000 RPM |
| Supply voltage | Up to 370 VDC |
| Power | Up to 56 kW, by stacking |
| Efficiency | Up to 96% |
| Operating temperature | -40 to +60 °C |
| Protection | Up to IP67 |
| Weight | Up to 50% lighter than conventional motors of the same output |
| Lifetime | Up to 20 years |
These are the limits of the platform. A given design reaches some of them, not all at once, and the configurator shows what your own specification delivers.
Custom vs Off-the-Shelf at a Glance
Neither is better in general. They are good at different things, and the honest comparison has a column for each:
| Off-the-shelf motor | Custom electric motor | |
|---|---|---|
| Fit to your application | Adapt the application: gearbox, oversizing, voltage workarounds | Designed for your torque, speed, voltage and envelope |
| Lead time | Days, from stock | About 20 to 50 days of parts after the design is final |
| Cost at high volume | Low, spread over thousands of units | Engineering fee spread over your units; viable from about 8 to 10 |
| Cost for one unit | Low | Higher, because the whole design cost sits on one motor |
| Efficiency at your duty cycle | High at the rated point, varies elsewhere | Efficiency island placed over your operating points |
| Weight and size | Fixed by the catalogue | Set by you, down to naked or wet designs |
| Changes later | Pick another model | Change a parameter and re-simulate |
If your column on the left wins, buy off the shelf. If your column on the right wins, read on.
Where Custom Electric Motors Are Used
- Drones, VTOL and aerospace: see aerospace electric motor design and our VTOL cargo drone concept.
- Wheels and mobility: e-bikes, wheelchairs, wheeled robots, see axial flux hub motors.
- Robotics: joint actuators where weight and flat shape matter, see the robot joint actuator guide.
- Pumps and wet environments: motors that run in the fluid, see canned motors and wet motors.
- Space: extreme temperatures and a high price per launched kilogram, see the Mars mobile concept.
What a Custom Electric Motor Costs, and How Long It Takes
Most manufacturers of custom electric motors will not publish a price. We do. Configuring and simulating your motor is free. Engineering starts at €6,000 for the electrical design, with optional mechanical design and materials of typically €4,000 to €12,000 on top. The minimum order is one motor, and the cost per motor becomes economically viable from about 8 to 10 motors. The live estimator is on the pricing page, and the logic behind it is explained in how much an axial flux motor costs.
Lead time after the design is final: PCB stators usually 20 working days, structural parts about 14 days, and rotors up to 50 days because of neodymium magnet procurement. They run in parallel, so the magnets set the pace.
Custom Electric Motor Manufacturers: Seven Questions Worth Asking
Whoever you choose, ask the same questions. The answers sort suppliers faster than any brochure:
- Who does the electromagnetic design, and can I meet them?
- Is the quoted performance simulated, measured, or copied from a similar motor?
- Is the torque continuous or peak, and at what temperature rise?
- What is the minimum order, and what happens to the price at ten units?
- Which parts are made in-house, and what is the lead time for each?
- What do I receive besides the motor: drawings, test data, a winding report?
- What happens when I need a revision?
For axial flux specifically, the axial flux motor manufacturers guide compares business models and how to read their datasheets, and the About page says who we are and where we sit.
How Ordering a Custom Motor Works Here
- Configure your motor in the configurator. Enter torque, speed, voltage and the envelope you have.
- Simulate it. The results show performance across your operating range, for free on the Community plan.
- Decide. If the motor does not fit, change the inputs or walk away. Nothing has been spent.
- Order. Engineering, then parts in about 20 to 50 days depending on the magnets.
- Integrate. Housed, naked or wet, to suit your structure.
Unsure what numbers to start with? The motor selector guide shows how to get them from your load, and the Configurator Guide walks through every screen.
Frequently Asked Questions
What is a custom electric motor?
A custom electric motor is designed for one application: its winding, magnets, air gap, diameter and stack count are chosen from the required torque, speed, voltage and installation space, instead of being picked from a catalogue range. Adding a different shaft or connector to a standard motor is a modification, not a custom design.
How much does a custom electric motor cost?
With Turncircles, customizing and simulating are free. Engineering starts at €6,000 for the electrical design, plus optional mechanical design (€6,000) and materials, typically €4,000 to €12,000 per order. The minimum order is one motor. All prices exclude VAT; see the pricing page.
How long does it take to get a custom electric motor?
The configuration and simulation are available immediately in the configurator. After the design is final, parts take up to about 50 days, driven by neodymium magnet procurement. PCB stators usually take 20 working days and structural parts about 14 days.
What is the minimum order for a custom electric motor?
One motor. The cost per motor becomes economically viable from about 8 to 10 motors, because the engineering fee is then spread over more units.
Do you make custom AC or brushed DC motors?
No. We build permanent magnet brushless axial flux motors, driven by an electronic three-phase drive from a DC supply. For brushed DC or mains-driven induction motors a catalogue manufacturer is the better choice.
Can I get a custom motor design without buying the motor?
Yes. You can run the analysis and have the electrical design done without ordering any motor. Materials are not charged for design-only work.
Define your own specifications
Configure a custom axial flux electric motor in minutes, simulate it for free, and decide when you have seen the results.
Configure your motor Talk to an engineer