Neodymium Cylinder Magnet – 8mm x 25mm | N42

The Neodymium Cylinder Magnet – 8mm x 25mm | N42 is a high-performance rare earth permanent magnet measuring 8mm in diameter x 25mm long. Manufactured from N42 grade Neodymium Iron Boron (NdFeB), this cylindrical magnet provides strong magnetic performance relative to its compact dimensions and is suitable for industrial, engineering, sensing, holding, positioning, manufacturing and OEM applications.

Also known as an N42 neodymium rod magnet, rare earth cylinder magnet, NdFeB cylinder magnet or cylindrical neodymium magnet, its elongated 25mm body makes it useful for incorporation into equipment, sensors, fixtures, product housings, prototypes and custom magnetic assemblies.

As a permanent magnet, this N42 cylinder requires no electricity, batteries or charging to maintain its magnetic field.

Key Features

• 8mm diameter x 25mm length
• N42 magnetic grade
• Neodymium Iron Boron (NdFeB)
• High-performance rare earth permanent magnet
• Cylindrical / rod-shaped design
• 25mm elongated body
• Strong magnetic performance relative to size
• Suitable for compact engineering applications
• Useful for holding and positioning
• Suitable for sensing and product integration
• Permanent magnetic operation
• No electricity or batteries required
• Suitable for custom and OEM assemblies

Common Applications

• Industrial equipment
• Engineering assemblies
• Sensors and switches
• Magnetic positioning
• Holding applications
• Product manufacturing
• Machinery
• Fixtures
• Prototypes
• Research and development
• Educational projects
• Custom magnetic assemblies
• OEM products

8mm Diameter x 25mm Long Cylinder Magnet

This neodymium magnet measures 8mm in diameter x 25mm long, giving it an elongated cylindrical profile.

The 25mm length is more than three times its diameter, making this magnet suitable for applications where a narrow magnetic component with an extended cylindrical body is required.

Potential installation locations include:

• Cylindrical recesses
• Product housings
• Sensor assemblies
• Mechanical components
• Fixtures
• Prototype equipment
• Custom manufactured parts

The 8mm x 25mm dimensions describe the physical size of the magnet and should not be interpreted as a pull-force or load-capacity rating.

N42 Grade Neodymium Magnet

This cylinder magnet is manufactured from N42 grade Neodymium Iron Boron.

N42 is a high-performance NdFeB magnetic grade commonly used in compact permanent magnetic components where strong magnetic properties are required.

The N42 designation relates to the magnetic material's properties. It does not by itself specify the finished magnet's pull force, holding capacity or Gauss reading.

Finished magnetic performance also depends on the magnet's geometry, magnetisation direction, target material and complete magnetic circuit.

Neodymium Iron Boron Rare Earth Magnet

Neodymium Iron Boron (NdFeB) is one of the strongest commercially available permanent magnetic materials.

Its high magnetic performance relative to physical size makes neodymium particularly useful for:

• Compact equipment
• Sensors
• Magnetic assemblies
• Industrial fixtures
• Product manufacturing
• Engineering systems
• OEM components

This allows strong permanent magnetic fields to be incorporated into applications where installation space may be limited.

Cylinder and Rod Magnet Applications

The elongated shape of a cylinder magnet provides different design possibilities from a thin disc or rectangular block magnet.

Cylinder magnets can be incorporated into:

• Round drilled or moulded recesses
• Tubular housings
• Sensor systems
• Mechanical assemblies
• Positioning systems
• Product components
• Prototypes

The most suitable installation method depends on the magnetisation direction and mechanical design of the complete assembly.

Magnetisation Direction

The magnetisation direction for this 8mm x 25mm N42 cylinder magnet has not been supplied.

Cylinder magnets may be manufactured with different magnetisation configurations, and the location of the north and south poles affects how the magnet interacts with other magnets and ferromagnetic targets.

For applications involving sensors, pole orientation, magnetic coupling or a specific magnetic field direction, the magnetisation direction should be confirmed before installation.

Magnetic Holding Performance

Actual magnetic performance depends on factors including:

• N42 magnetic grade
• Magnetisation direction
• Target steel thickness
• Steel composition
• Available contact area
• Surface flatness
• Air gaps
• Paint and coatings
• Adhesive layers
• Magnet orientation
• Load direction
• Magnetic circuit design

No specific pull force or Gauss rating has been supplied for this product and these values should not be inferred solely from the N42 grade or 8mm x 25mm dimensions.

Magnetic Attraction Decreases with Distance

Magnetic attraction decreases rapidly as the distance between a magnet and its target increases.

Layers that can create an air gap include:

• Paint
• Adhesive
• Plastic
• Protective coatings
• Paper
• Fabric
• Dirt
• Surface irregularities

Where maximum attraction to steel is required, close contact with clean, flat and sufficiently thick ferromagnetic material generally provides the best practical performance.

Direct Pull vs Shear Force

Magnetic holding performance varies according to the direction in which a load is applied.

Direct pull occurs when force attempts to separate the magnet perpendicular to the steel surface.

Shear force occurs when a load acts parallel to the target surface and encourages the magnet to slide.

Practical holding capacity in vertical, angled or dynamic applications may therefore be considerably different from ideal direct-pull performance.

Bonding Neodymium Cylinder Magnets

Cylinder magnets are often bonded into compatible housings, holes and recesses.

Before bonding:

• Ensure the magnet and substrate are clean
• Select an adhesive compatible with both materials
• Avoid adhesives or curing conditions that exceed the magnet's temperature limits
• Follow the adhesive manufacturer's preparation and curing instructions
• Allow adequate curing before applying mechanical or magnetic loads

Where the magnet is inserted into a close-fitting recess, avoid forcing it into place, as neodymium magnetic material is brittle.

Compatible Target Materials

Neodymium magnets attract ferromagnetic iron and compatible steels.

Suitable target materials may include:

• Mild steel
• Iron
• Magnetic steel
• Ferromagnetic machinery components
• Compatible steel plates and brackets

They will not effectively attract:

• Aluminium
• Copper
• Brass
• Plastic
• Timber
• Glass

Many stainless steel grades may also provide weak or negligible magnetic attraction and should be tested before use.

Neodymium vs Ferrite Cylinder Magnets

Both neodymium and ferrite are permanent magnetic materials, but neodymium generally provides substantially greater magnetic performance relative to its physical size.

Neodymium magnets typically offer:

• High magnetic strength relative to size
• Compact dimensions
• Suitability for precision and high-performance assemblies

Ferrite magnets are generally:

• More economical
• Naturally corrosion resistant
• Lower in magnetic strength relative to size
• Suitable for many general-purpose applications

N42 neodymium can be particularly useful where compact dimensions and strong magnetic properties are important.

Permanent Magnetic Operation

This N42 cylinder is a permanent magnet, requiring no external electrical power to maintain its magnetic field.

It requires:

• No electricity
• No batteries
• No charging
• No electrical wiring

The magnetic field remains continuously active during normal use.

Technical Specifications

• Product Type: Neodymium Cylinder Magnet
• Alternative Names: Neodymium Rod Magnet, N42 Cylinder Magnet, Rare Earth Cylinder Magnet, NdFeB Cylinder Magnet, Cylindrical Neodymium Magnet
• Diameter: 8mm
• Length: 25mm
• Shape: Cylinder / Rod
• Magnetic Material: Neodymium Iron Boron (NdFeB)
• Magnetic Grade: N42
• Magnet Type: Rare Earth Permanent Magnet
• Magnetic Operation: Permanent
• Power Required: None
• Target Material: Compatible ferromagnetic iron and steel
• Primary Functions: Magnetic holding, positioning, sensing and integration into magnetic assemblies
• Typical Applications: Industrial equipment, engineering, sensors, manufacturing, prototypes and OEM products

Industrial, Engineering and OEM Applications

The combination of N42 magnetic material and an 8mm x 25mm cylindrical profile makes this magnet suitable for integration into a broad range of engineered products.

Potential users include:

• Engineers
• Product designers
• Equipment manufacturers
• Machinery builders
• Sensor manufacturers
• Prototype developers
• Research laboratories
• OEM manufacturers

For technical applications, the magnet should be evaluated as part of the complete magnetic circuit and mechanical assembly.

Handling Neodymium Cylinder Magnets

Neodymium magnets can generate strong attraction and should be handled carefully.

NdFeB magnetic material is also hard and brittle and can chip, crack or fracture if magnets:

• Snap forcefully together
• Strike steel surfaces
• Are dropped
• Experience excessive mechanical stress

Do not drill, cut or machine neodymium magnets using conventional methods.

Long, narrow cylinder magnets should also be protected from excessive sideways mechanical loads that could cause physical damage.

Please Note

This product is an N42 Neodymium Cylinder Magnet measuring 8mm in diameter x 25mm long.

No specific coating or plating, pull force, Gauss rating, magnetisation direction, dimensional tolerance or maximum operating temperature has been supplied and these specifications should not be assumed.

Actual magnetic performance depends on the N42 magnetic material, magnetisation direction, target steel thickness and composition, available contact area, air gaps, surface condition, magnet orientation and load direction.

Neodymium Iron Boron is a hard and brittle magnetic material. Avoid drilling, cutting, machining, impact and uncontrolled collisions between magnets.

Strong neodymium magnets can create pinch hazards. Keep magnets away from children, pacemakers and other medical implants, magnetic storage media and sensitive electronic equipment.