Powerful Countersunk – Rectangular Rare Earth Neodymium Block Magnets for DIY, Crafts, Woodworking, Engineering & More

Understanding Neodymium Magnets

Neodymium (NdFeB) magnets are known for their exceptional magnetic strength, making them the strongest type of permanent magnet on the market. Their compact size allows them to deliver high magnetic force even in space-constrained applications. In construction, they help securely position metal components during assembly, while in the medical sector, they play a vital role in the consistent performance of imaging systems and sensitive equipment. From everyday home tasks to demanding industrial operations, these magnets ensure dependable, long-lasting functionality.

30mm x 7.8mm x 2mm Neodymium Block Countersunk – Nickel Coated Magnet

These robust 30mm x 7.8mm x 2mm N38 Neodymium Mounting Magnets deliver an impressive 17.4KG pull force—ideal for wall or surface mounting. The reinforced steel channel shields the magnet from high-impact damage, significantly extending its lifespan compared to standard countersunk block magnets.

Perfect for secure flat-surface applications, these channel magnets are widely used as magnetic door latches, display holders, or sign mounts—combining strength with durability for long-term performance.

Magnet Grade: N38

N35 grade neodymium magnets offer a balanced combination of strength and versatility, with a maximum energy product of around 36-39  MGOe. Well-suited for various applications including motors, sensors, and precision assemblies, they deliver consistent magnetic performance. Their reliable field strength makes them a preferred choice for consumer electronics and technical equipment alike. Widely adopted across industries, N38 magnets are valued for their dependable and efficient performance.

Surface Finish: Ni-Cu-Ni Coating

These magnets are finished with a durable triple-layer Ni-Cu-Ni (Nickel-Copper-Nickel) coating that enhances corrosion resistance and maintains a clean, professional look. This layered shield protects the magnet’s core from oxidation and wear in mildly humid environments, making it suitable for long-term use in a range of settings. For more aggressive environments, epoxy or other advanced coatings may offer enhanced protection.

APPLICATION EXAMPLES

Material Neodymium (NdFeB)

Product Name: Powerful Countersunk – Rectangular Rare Earth Neodymium Block Magnets for DIY, Crafts, Woodworking, Engineering & More

Shape: Channel, Mounting, Block, Countersunk

Magnetic Grade: N38 (Br ≥ 12.6 kGs, Hcj ≥ 12 kOe)

Dimensions: L30mm x 7.8mm x 2mm (customizable)

Hole: Two (3.3mm c/s holes)

Dimensional Tolerance: Length ±0.05mm, Width ±0.05mm, Thickness ±0.05mm

Operating Temperature: ≤80°C (high-temp version available)

Density: ≥7.5 g/cm³

Max Gauss: 1850

Pull (KG): 17.04KG

Surface Magnetic Field: 3800 ±200 Gauss (measured with TM-801 Gauss meter)

Magnetic Flux: 2.3 mWb (measured with fluxmeter)

Manufacturing Process

The product is manufactured through the following key processes:

● A high-speed grinding wheel shapes the magnet's surfaces with tight dimensional tolerances.

● Coolant fluid is applied to control heat, reduce surface stress, and ensure a smooth finish.

● The result is a uniform, precisely dimensioned magnet with clean edges—ideal for high-performance applications.

This precision step is essential for ensuring that the final magnets meet strict quality standards for use in motors, sensors, electronics, and aerospace components  

Surface Treatment & Plating

To enhance corrosion resistance and appearance:

Default Plating: Triple-layer Ni-Cu-Ni (customizable).

Standard Thickness: Epoxy (12μm)

Optional Plating: Single-layer Zn (5μm) for cost-sensitive projects.

Features:

✔ Salt spray & oxidation resistance

✔ Increased surface hardness (scratch-resistant)

✔ Improved gloss (ideal for exposed components)

Appearance & Dimensional Inspection

Visual Inspection: Under standardized lighting, trained QC staff check for cracks, chipping, inclusions, pores, or oxidation

Applications

Electric Motors & Generators
Application: Precision-engineered magnets are employed in stators, rotors, and brushless DC motors to enhance magnetic flux density, efficiency, and torque performance.

Consumer Electronics
Application: High-performance neodymium magnets are integrated into speakers, haptic systems, vibration motors, and sensors, contributing to compact design and reliable functionality.

Packaging & Transportation

Defect Elimination: 100% inspection using calipers, projectors, visual checks, and automated systems to reject cracked, chipped, oxidized, or coated-defective magnets.

Uniform Magnetization & Structured Arrangement: Magnets are uniformly magnetized and arranged for optimal packaging based on customer requirements to ensure performance and facilitate automated assembly.

Vacuum Sealed Packaging: Multi-layer vacuum sealing with moisture barriers, desiccants or nitrogen, prevents corrosion and magnetic interference during storage and shipping.

Customized Outer Packaging: Shock-proof, moisture-resistant, and anti-magnetic leakage packaging (e.g., multilayer cartons, plastic boxes, metal shielding) ensures compliance with international logistics standards. Each box includes a product list, labels, and tracking codes.

With deep expertise in magnetic materials, we deliver solutions for industries like EVs, smart manufacturing, and electronics. Our strong technical capabilities and product consistency have earned the trust of customers worldwide.

Usage Precautions？

● Handle gently: Avoid impacts/drops (brittle material).

● Prevent pinching: Slide magnets apart—do not pry.

● Polarity check: Install correctly to avoid malfunctions.

● Avoid moisture/acids: Store in dry, mild environments.

● Keep away from sensitive devices: Hard drives, IC cards, pacemakers, etc.

Customization & Services

● Custom magnet size, shape, and coating (layers, thickness, color)

● Tailored magnetization direction and field strength

● Laser engraving service for logos or serial numbers

● Packaging and suction force testing for special applications

Please contact us for free samples, magnet customization solutions, and MSDSRoHS, ISO 9001, QC080000, IATF 16949, ISO 14001, ISO 27001 or other relevant certificates!

We’re here to help!

 Phone/WhatsApp/WeChat: +86 180 3822 5893

Email: sales@jinconn.com

Website: www.jinconnmagnet.com

Address: Xiaohe Industrial Zone, Daojiao Town, Dongguan City, Guangdong, China