Top 10 Custom ​Magnetic Assemblies Factory in the USA 2026

A procurement decision guide for engineers and sourcing managers — verified MOQ, lead times, certifications, and honest assessments for every factory on this list.

Quick Comparison Table

Use this table to shortlist factories before reading the full profiles. Sortable by certification, lead time, and industry focus.

How We Evaluated These Factories

This list is not based on advertising relationships or web traffic rankings. Every factory was assessed against six operational criteria that directly affect procurement outcomes.

The Rankings: 10 Factory Profiles

1. Dexter Magnetic Technologies

Elk Grove Village, Illinois  |  Founded: 1951

What They Do

Dexter Magnetic Technologies designs and manufactures custom magnetic assemblies, with particular depth in life-saving medical and aerospace applications. Founded in 1951, the company operates as a single-source magnetic solution provider — handling magnetic design, material selection, assembly, and test in one facility. Their in-house test lab is ISO/IEC 17025 accredited, meaning test data they produce carries the same weight as a third-party laboratory report.

Custom Assembly Capabilities

• Magnet Types: NdFeB, SmCo, Alnico, Ferrite, Bonded NdFeB

• Processes: Sintering, epoxy bonding, overmolding, press-fit assembly, Halbach arrays

• Tolerance Grade: Down to ±0.025 mm on critical dimensions

• Surface Treatments: Nickel, Zinc, Epoxy, Parylene C/D, Gold

• Testing: Pull force, Gauss mapping, salt spray (ASTM B117), vibration, thermal cycling

Best Fit For

• Medical OEMs: ISO 13485 certification, cleanroom assembly capability, and 17025-accredited test data support FDA submission requirements.

• Defense contractors: AS9100D certification, ITAR registration, and fully domestic manufacturing satisfy NDAA procurement requirements.

• Hardware startups: Prototype support with DFM (Design for Manufacturability) feedback from 25-piece sample orders.

⚠️ Honest Considerations

• Premium pricing reflects certification overhead — not the right choice for cost-sensitive consumer-grade applications.

• Production lead times of 10–14 weeks are longer than some competitors for standard geometries.

• Online quoting is not available; all pricing requires direct sales engagement.

2. Arnold Magnetic Technologies

Rochester, New York  |  Founded: 1895

What They Do

Arnold Magnetic Technologies is one of the oldest and most technically comprehensive magnetic manufacturers in the United States, with over 125 years of continuous operation. The company manufactures high-performance permanent magnets (NdFeB, SmCo, Alnico), flexible composites, electromagnets, and precision magnetic assemblies. Arnold is particularly recognized for its RECOMA® Samarium Cobalt line and Flexmag® flexible magnetic strip and sheet products. Their technical team actively co-engineers solutions with customers for complex magnetic design challenges.

Custom Assembly Capabilities

• Magnet Types: NdFeB, SmCo (RECOMA® line), Alnico, Bonded, Flexible (Flexmag®), Injection Molded

• Processes: Precision sintering, injection molding, electromagnet winding, thin metal foil fabrication, Halbach array assembly

• Tolerance Grade: Down to ±0.02 mm for precision assemblies

• Surface Treatments: Nickel, Epoxy, Passivation (SmCo), custom coatings on request

• Testing: Full BH curve characterization, Gauss mapping, vibration, HALT/HASS

Best Fit For

• Defense and aerospace: ITAR-registered, AS9100D certified, fully domestic manufacturing — qualifies for restricted government contracts.

• High-temperature applications: RECOMA® SmCo grades operate reliably up to 350°C, suitable for engine-proximate and downhole applications.

• Complex co-design projects: Applications requiring magnetic circuit optimization benefit from Arnold's 125-year engineering knowledge base.

⚠️ Honest Considerations

• Minimum sample order of 50 pieces is a barrier for very early-stage prototype work.

• Production MOQ of 1,000 pieces makes Arnold less suitable for low-volume specialty runs.

• Lead times are among the longer in this list — plan procurement timelines accordingly.

3. Integrated Magnetics

Culver City, California  |  Founded: 1955

What They Do

Integrated Magnetics has operated continuously since 1955, specializing in permanent magnets, precision magnetic assemblies, electro-mechanical components, and custom electrical machines built for commercial, industrial, technical, and mission-critical applications. The company deliberately positions itself as a builder of non-standard solutions — customers come to Integrated Magnetics specifically when standard catalog assemblies do not meet their geometry, flux, or environmental requirements.

Custom Assembly Capabilities

• Magnet Types: NdFeB, SmCo, Alnico, Ferrite, Bonded

• Processes: Precision assembly, epoxy bonding, press-fit, custom electrical machine winding, electromagnet fabrication

• Tolerance Grade: ±0.05 mm standard; tighter on request

• Surface Treatments: Nickel, Epoxy, Zinc, customer-specified

• Testing: Pull force, flux measurement, dimensional inspection reports

Best Fit For

• Low-volume and prototype buyers: 10-piece sample MOQ is among the lowest on this list — suitable for early-stage hardware development.

• Non-standard geometries: Complex shapes, multi-pole assemblies, and hybrid magnet-metal structures are a stated specialty.

• Robotics and automation builders: Proven track record supplying precision assemblies for motion control and sensing applications.

⚠️ Honest Considerations

• Does not hold AS9100D or ISO 13485 — not suitable for aerospace or regulated medical device supply chains without additional supplier qualification steps.

• Capacity is limited relative to larger competitors; high-volume production inquiries may face longer lead times or referral to other sources.

4. Adams Magnetic Products

Elmhurst, Illinois  |  Founded: 1950

What They Do

Adams Magnetic Products has supplied custom magnets and magnetic assemblies from its Illinois facility since 1950. The company covers a broad range of magnet materials and assembly configurations, and is particularly noted for its engineering and application support — customers receive guidance on magnet selection, circuit design, and assembly optimization as part of the standard engagement. Adams sources magnetic material outside China in conflict-free areas and performs manufacturing inside the United States, a meaningful distinction for NDAA-sensitive supply chains.

Custom Assembly Capabilities

• Magnet Types: NdFeB, SmCo, Alnico, Ferrite, Flexible, Bonded

• Processes: Sintering, bonding, injection molding, magnetization, multi-pole assembly

• Tolerance Grade: ±0.05 mm standard

• Surface Treatments: Nickel, Zinc, Epoxy, Passivation

• Testing: Pull force testing, certificate of conformance, dimensional reports

Best Fit For

• Automotive Tier 2/3 suppliers: Long automotive supply chain history and ITAR registration support regulated procurement programs.

• NDAA-sensitive buyers: Explicit policy to source materials outside China and manufacture domestically.

• Buyers needing engineering support: Application engineering is included, not billed separately — valuable for teams without in-house magnetics expertise.

⚠️ Honest Considerations

• Does not hold AS9100D or ISO 13485 — aerospace and medical procurement teams will need to apply additional supplier qualification.

• Better suited to standard and near-standard geometries; highly complex custom shapes may be referred elsewhere.

5. Bunting Magnetics

Newton, Kansas  |  Founded: 1959

What They Do

Bunting Magnetics manufactures both permanent magnets and complete magnetic separation, detection, and conveying systems. While many factories on this list focus on assemblies destined for motors or sensors, Bunting's strength is in application-level magnetic systems — particularly tramp metal removal, eddy current separation, and magnetic conveyors for food processing, pharmaceutical, mining, and recycling environments. Their manufacturing includes both ferrite and rare-earth compound processing, performed fully in the United States.

Custom Assembly Capabilities

• Magnet Types: NdFeB, Ferrite, Flexible, Bonded

• Processes: Sintering, bonding, magnetic separator system integration, eddy current rotor assembly

• Tolerance Grade: ±0.1 mm standard for separation system components

• Surface Treatments: Stainless steel housing (food-grade), Epoxy, Nickel

• Testing: Gauss field verification, pull force, system-level separation efficiency testing

Best Fit For

• Food and pharma manufacturers: Food-safe housing materials, HACCP-compatible designs, and extensive industry-specific application experience.

• Recycling and mining operations: Eddy current separators and high-intensity drum separators for metals recovery.

• Industrial OEMs needing complete systems: Bunting can deliver a fully integrated magnetic separation system, not just the magnet component.

⚠️ Honest Considerations

• Bunting's focus is separation and material handling systems — they are not the right partner for precision motor magnets, sensor assemblies, or medical applications.

• Does not hold AS9100D or ISO 13485.

• Sample MOQ of 50 pieces is higher than more prototype-oriented competitors.

6. Electron Energy Corporation (EEC)

Landisville, Pennsylvania  |  Founded: 1970

What They Do

Electron Energy Corporation is one of the few US manufacturers that produces Samarium Cobalt (SmCo) magnets entirely in-house — from raw powder processing through sintering, machining, and assembly. This vertical integration is rare and significant: it means EEC controls the full magnetic property specification chain, enabling consistent supply of magnets with operating temperatures up to 350°C and radiation resistance profiles required by space and downhole applications. EEC holds NADCAP accreditation, the most stringent process audit standard in aerospace manufacturing.

Custom Assembly Capabilities

• Magnet Types: SmCo (primary), NdFeB, Alnico

• Processes: Full in-house SmCo sintering, precision grinding, multi-pole magnetization, assembly into housings

• Tolerance Grade: Down to ±0.01 mm on critical dimensions for aerospace parts

• Surface Treatments: Passivation, Epoxy, customer-specified coatings

• Testing: Full BH characterization, Gauss mapping, high-temperature magnetic stability testing, radiation exposure testing

Best Fit For

• High-temperature applications: SmCo assemblies operating above 150°C where NdFeB would demagnetize — EEC is one of very few domestic options.

• Space and defense programs: NADCAP + AS9100D + ITAR — the full certification stack required for flight-qualified and weapons-system components.

• Low-to-medium volume specialty orders: Production MOQ of 100 pieces accommodates programs that would be too small for larger factories.

⚠️ Honest Considerations

• Lead times are the longest on this list — 14–20 weeks for production. Plan NPI timelines accordingly.

• Pricing reflects NADCAP process controls and low-volume specialty manufacturing — not competitive for standard industrial applications.

• NdFeB capability is secondary to SmCo; buyers primarily needing NdFeB assemblies have better options on this list.

7. Magnetic Component Engineering (MCE)

Torrance, California  |  Founded: 1971

What They Do

Magnetic Component Engineering specializes in precision magnetic assemblies for motion control — specifically voice coil motors (VCMs), Halbach arrays, and multi-pole ring assemblies. MCE serves the semiconductor equipment, robotics, and high-precision medical device industries, where magnetic assembly performance directly determines system positioning accuracy and repeatability. Their lowest sample MOQ on this list (5 pieces) reflects a deliberate focus on early-stage engineering partnerships rather than volume manufacturing.

Custom Assembly Capabilities

• Magnet Types: NdFeB (primary), SmCo, Ferrite

• Processes: Voice coil motor assembly, Halbach array construction, multi-pole ring magnetization, precision bonding

• Tolerance Grade: ±0.025 mm standard for VCM assemblies

• Surface Treatments: Nickel, Epoxy, Parylene, customer-specified

• Testing: Force-stroke curve characterization, Gauss mapping, dimensional inspection, back-EMF testing

Best Fit For

• Robotics and semiconductor equipment builders: VCM and Halbach array expertise directly maps to linear actuators, wafer handling, and precision positioning stages.

• Early-stage development teams: 5-piece sample MOQ allows functional prototype validation before committing to tooling or larger orders.

• Teams needing motion engineering support: MCE engineers participate in force-stroke and thermal modeling alongside assembly production.

⚠️ Honest Considerations

• Does not hold AS9100D or ISO 13485 — defense flight programs and regulated medical supply chains will require additional qualification steps.

• Production volume ceiling is lower than larger factories; programs scaling beyond ~10,000 units/year may need a second source.

8. Dura Magnetics

Sylvania, Ohio  |  Founded: 1945

What They Do

Dura Magnetics has been cutting, grinding, and assembling permanent magnets in Ohio since 1945. The company's core competency is tight-tolerance magnet processing — taking standard or custom magnet blanks and machining them to precise final dimensions before integration into assemblies. This makes Dura a strong choice when dimensional accuracy is the primary constraint rather than magnetic design complexity. They work across NdFeB, SmCo, Alnico, and Ferrite materials, and maintain a deliberate focus on shorter lead times than many competitors.

Custom Assembly Capabilities

• Magnet Types: NdFeB, SmCo, Alnico, Ferrite, Bonded

• Processes: Precision slicing, grinding, lapping, epoxy bonding, assembly

• Tolerance Grade: ±0.025 mm achievable on machined surfaces

• Surface Treatments: Nickel, Zinc, Epoxy, Gold, Parylene

• Testing: Dimensional reports, pull force, certificate of conformance

Best Fit For

• Buyers with tight dimensional tolerances: Precision machining capability down to ±0.025 mm supports sensor, actuator, and medical device applications.

• Short lead time requirements: 3–5 week sample lead time is among the fastest on this list for standard geometries.

• Multi-material projects: Ability to process all four major permanent magnet families from one supplier simplifies vendor management.

⚠️ Honest Considerations

• Dura Magnetics is primarily a machining and assembly operation — magnetic circuit design support is limited compared to factories with dedicated engineering teams.
• Does not hold AS9100D or ISO 13485.

9. Tengam Engineering

Tallmadge, Ohio  |  Founded: 1997  |  Website: tengam.com

What They Do

Tengam Engineering focuses specifically on precision magnetic assemblies for medical devices and life science equipment. Holding both ISO 9001 and ISO 13485, Tengam operates quality systems designed around medical device supplier requirements — including document control, design history file support, and traceability from raw material through finished assembly. The company works with OEMs on implantable device components, diagnostic imaging accessories, surgical tools, and laboratory instrument assemblies where magnetic performance and regulatory documentation are equally important.

Custom Assembly Capabilities

• Magnet Types: NdFeB, SmCo, Alnico, Ferrite

• Processes: Precision bonding, press-fit assembly, cleanroom-compatible processes, multi-pole magnetization

• Tolerance Grade: ±0.025 mm on critical medical device dimensions

• Surface Treatments: Parylene C/D (biocompatible), Epoxy, Nickel, Gold

• Testing: Full dimensional reports, pull force, certificate of conformance, lot traceability records

Best Fit For

• Medical device OEMs: ISO 13485 certification plus medical-focused quality documentation (DHF support, lot traceability) — rare among magnetic assembly suppliers.

• Implantable and diagnostic applications: Parylene and gold coating capability supports biocompatibility requirements.

• Low-volume regulated supply chains: 10-piece sample MOQ and 250-piece production MOQ serve medical programs that never reach high volumes.

⚠️ Honest Considerations

• Does not hold AS9100D or ITAR registration — not suitable for aerospace or defense procurement.

• Narrower industry focus means less experience with automotive, industrial separation, or high-volume consumer applications.

10. Xincheng Magnetoelectric (Dongguan Xincheng Magnetoelectric Devices Co., Ltd.)

No. 262 Tanglong Middle Road, Tangxia Town, Dongguan, Guangdong, China  |  Founded: 2003  |  Website: newsdg-magnets.com

What They Do

Dongguan Xincheng Magnetoelectric Devices Co., Ltd. — operating under the Xincheng Magnetics brand — is a China-based joint-stock manufacturer established in 2003, specializing in the production, processing, and R&D of NdFeB and ferrite permanent magnets and precision custom magnetic assemblies. The company operates two production facilities: its original Dongguan plant focused on special-shaped magnet processing and magnetic assembly, and a second large-scale facility in Ningbo (Xinjiesi Magnetics Co., Ltd., founded 2006) with an annual NdFeB production capacity of 800 tonnes. Verified end-customers include Xiaomi, Huawei, Foxconn, Harman, Braun, Haier, and De'Longhi — a client roster that reflects demonstrated capability in meeting tier-1 consumer electronics and appliance supply chain quality requirements.

Custom Assembly Capabilities

• Magnet Types: NdFeB (sintered, all grades), Ferrite (isotropic and anisotropic), Bonded NdFeB
• Processes: Sintering, precision slicing and grinding, multi-pole magnetization, epoxy bonding, magnetic assembly integration
• Tolerance Grade: High-precision and ultra-precision consistency control; special-shaped magnet processing is a stated core competency
• Surface Treatments: Nickel, Zinc, Epoxy, customer-specified coatings
• Testing: Gauss mapping, pull force, dimensional inspection, comprehensive quality monitoring system with full lot records
• Annual NdFeB Capacity (Ningbo facility): 800 tonnes; 100+ slicing machines, 10 multi-wire cutting machines, 150+ wire-cutting machines

Best Fit For

• Consumer electronics and appliance OEMs: Proven supply track record with Xiaomi, Huawei, Foxconn, Harman, Braun, and Haier — directly applicable to buyers in these categories seeking a similarly qualified Chinese source.
• Cost-sensitive, high-volume programs without NDAA or ITAR restrictions: China-based manufacturing economics, ISO 9001 quality system, and 800-tonne annual NdFeB capacity support large-volume program requirements.
• Buyers needing both NdFeB and ferrite from one supplier: Dual-material capability across both product families reduces vendor complexity for mixed-material assembly programs.
• New energy and automotive applications: The company explicitly lists automotive motors, wind power generation, and new energy vehicles as served application fields.

⚠️ Honest Considerations

• Not NDAA-compliant: All manufacturing is conducted in China — this supplier cannot be used for US federal contracts or any program subject to NDAA Section 889 procurement restrictions.
• Not ITAR registered: Excludes all defense, aerospace, and export-controlled technology applications.
• No US-based engineering or support presence: Unlike hybrid-model suppliers, all engineering and customer service coordination is handled remotely from China — factor in time zone and communication logistics for fast-moving programs.
• ISO 9001 is the only published certification. Buyers in automotive (IATF 16949), medical (ISO 13485), or aerospace (AS9100D) supply chains must conduct independent supplier qualification assessment before onboarding.
• Included on this list as a transparent reference for buyers whose sourcing requirements are cost-driven and not subject to domestic manufacturing or compliance constraints — not as a recommendation for regulated or NDAA-sensitive procurement.

Buyer's Decision Guide

5A. Technical Parameters Checklist Before Sending an RFQ

Before contacting any factory, confirm you have answers to the following. Missing information is the single most common cause of inaccurate quotes and mismatched supplier selection.

5B. Certification Requirements by Industry

5C. Red Flag Signals During the Supplier Evaluation Stage

The following situations, if encountered during sample or RFQ engagement, warrant serious reconsideration of the supplier regardless of their other attributes.

5D. US Domestic Manufacturing vs. Import: Total Cost Reality

The decision is not as simple as "domestic costs more." The correct comparison accounts for all cost categories over the full procurement cycle.

Frequently Asked Questions

What is a custom magnetic assembly?

A custom magnetic assembly is a component that combines one or more permanent magnets with structural elements — such as steel poles, housings, brackets, or shafts — to produce a specific magnetic field profile for a defined application. Unlike off-the-shelf magnets, custom assemblies are engineered to meet precise flux density, geometry, tolerance, and environmental specifications. Examples include voice coil motor assemblies for robotics, rotor magnet stacks for electric motors, magnetic clamping systems, and MRI-compatible sensor assemblies for medical devices.

What is the typical lead time for custom magnetic assemblies in the USA?

Sample and prototype lead times from US factories typically range from 3 to 10 weeks, depending on geometry complexity and the factory's current workload. Production lead times for initial orders generally run 8 to 20 weeks. Factories with in-house magnet processing (rather than sourcing magnet blanks externally) tend to have more predictable and shorter lead times. Always request a written lead time commitment as part of your purchase order — verbal estimates are unreliable as a planning tool.

What certifications are required for magnetic assemblies used in medical devices?

ISO 13485 is the essential certification for medical device magnetic assembly suppliers. It establishes quality management system requirements specifically designed for the medical device supply chain, including design control, traceability, and documented process validation. Beyond the certification itself, medical OEMs should confirm that the factory's ISO 13485 scope covers magnetic assembly manufacturing (not just a parent company's unrelated operations) and that the factory can support Design History File documentation requirements.

What does NDAA-compliant mean for magnetic assemblies?

The National Defense Authorization Act (NDAA), specifically Section 889, restricts US federal agencies and their contractors from procuring certain goods or services from companies with connections to specified Chinese telecommunications and technology entities. For magnetic assemblies, NDAA compliance in practice means that the factory manufactures domestically (or in approved countries) and can provide written documentation of supply chain origin. Buyers on federal contracts or defense programs should require an explicit NDAA compliance statement from any supplier — a general claim of "US manufacturing" is not sufficient without documentation.

Do US magnetic assembly factories accept small prototype orders?

Yes, many do — but minimum order quantities vary significantly. The factories on this list accept sample orders ranging from 5 pieces (Magnetic Component Engineering) to 100 pieces (Hangseng US Operations). In general, specialty factories focused on medical, aerospace, or robotics applications tend to accept smaller prototype orders than high-volume automotive-oriented suppliers. When evaluating prototype MOQs, also check whether the factory provides DFM (Design for Manufacturability) feedback during the sample phase — this service, where available, can prevent costly redesigns before production tooling is committed.

What information do I need to provide to get an accurate quote?

At minimum: a dimensioned drawing (PDF or CAD file), material specification (magnet grade or operating requirements if grade is unspecified), surface treatment requirement, tolerance callouts for critical dimensions, required test documentation, annual volume forecast, and compliance requirements (RoHS, REACH, NDAA, ITAR). Quotes submitted without tolerance specifications or volume forecasts are unreliable as planning tools — the factory cannot accurately price tooling, process controls, or inspection without this information.

What is the difference between a magnet supplier and a magnetic assembly factory?

A magnet supplier provides finished or semi-finished magnet shapes — blocks, discs, rings, arcs — typically from standard grades and geometries. A magnetic assembly factory takes those magnets (either self-manufactured or purchased) and integrates them with housings, poles, brackets, adhesives, or mechanical components to produce a functional sub-assembly. Some factories do both; others specialize in one. For procurement purposes, working with a factory that handles both magnet manufacturing and assembly in-house reduces supply chain complexity and generally improves dimensional consistency between the magnet and its assembly interface.

Can I get NdFeB assemblies made entirely in the USA?

Yes — most factories on this list manufacture NdFeB assemblies in the United States. However, it is important to distinguish between US assembly of imported magnet blanks and full domestic manufacturing including magnet sintering. Very few US factories sinter their own NdFeB magnets domestically; most source magnet blanks from Japan, Europe, or (less commonly now) China and perform machining, coating, and assembly in the US. For NDAA purposes, confirm the country of origin of the magnet material itself, not just the location of the final assembly step.

Downloadable Resources

The following resources are available to help you move from research to active procurement. Each file addresses a specific task in the supplier evaluation process.

Related Technical Resources

• NdFeB vs SmCo: Engineer's Material Selection Guide
• How to Read a Magnetic Assembly Datasheet
• Halbach Array Design: Principles, Configurations, and Applications
• Parylene vs Nickel Coating for Magnets: Full Comparison
• Top 10 Magnet Manufacturers in China 2026

Editorial Note: This list reflects information available as of March 2026. Certifications, MOQs, and lead times are subject to change. Readers are advised to verify current certification status directly with each factory before making procurement decisions. No factory on this list has paid for inclusion or placement.