Sourcing Dual-Rotor Axial Flux Motors: An OEM Buyer's Guide

The Dual-Rotor Axial Flux Permanent Magnet (AFPM) motor—typically featuring a single coreless or yokeless stator sandwiched between two rotating magnet disks—provides maximum torque density in modern electric machine design. It is the architecture of choice for high-end hypercars, advanced eVTOL drones, compact humanoid robotics, and specialized marine propulsion.

However, transitioning from a theoretical design in Maxwell or Motor-CAD to a reliable, cost-effective production supply chain is challenging. If your engineering team has specified a dual-rotor AFPM motor, your procurement team needs to know exactly what to scrutinize when qualifying an OEM manufacturing partner.

Here are the four critical manufacturing hurdles you must evaluate during the RFQ process.

1. Validating Structural Deflection and Airgap Control

The most critical manufacturing challenge of a dual-rotor AFPM motor is managing the immense axial attractive force between the two rotors. High-grade neodymium (NdFeB) magnets on opposing disks are constantly pulling toward each other with forces that can easily exceed several thousands of Newtons, depending on the motor diameter.

A slight deflection in the rotor disks (backing plates) or a minute tolerance error in the thrust bearings can cause the airgap to close. If the spinning magnets contact the stator, the motor destroys itself instantly.

2. High-Speed Magnet Retention and Eddy Current Losses

In an axial flux motor, the magnets are mounted on the flat face of the rotor disk. As RPM increases, centrifugal forces shear the magnets outward. At high electrical frequencies, the magnets themselves can heat up rapidly due to Eddy currents induced by stator slot harmonics.

3. Stator Manufacturing: Winding, Litz Wire, and Thermal Bottlenecks

In a dual-rotor design, the stator is trapped in the middle. It generates the vast majority of the heat, but has very little surface area exposed to ambient air. To combat high-frequency skin effects, many high-end AFPM motors require Litz wire (hundreds of individually insulated microscopic copper strands twisted together) or perfectly aligned rectangular wire.

4. Customization Flexibility and Tooling Costs

Unlike radial motors—where you can simply stack more standard silicon steel laminations to increase the axial length and power of the motor—modifying an axial flux motor often requires completely new, expensive tooling for the rotor disks, stator molds, and housings.

Partnering with AFPMMotor

Manufacturing dual-rotor AFPM motors requires specialized process control, especially around stator winding, vacuum resin potting, rotor balance, airgap control, and magnet retention. Buyers should not assume a standard radial motor supplier can transfer the same fixtures and inspection plan to a pancake motor program without additional validation.

At AFPMMotor, RFQ reviews focus on the axial flux details that most often create sourcing risk: dynamic balancing of dual-rotor assemblies, thermally conductive stator potting, magnet retention, housing stiffness, and manufacturable acceptance criteria. The goal is to turn a drawing or target torque-speed map into a DFM review, sample plan, and pilot-lot evidence package before scale-up.

Ready to evaluate a supply chain for your next dual-rotor electric drive? Explore our OEM capabilities and send us your RFQ today.