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MP 20x8/4x5 / N38 - ring magnet

ring magnet

Catalog no 030333

GTIN/EAN: 5906301812272

5.00
Load capacity 6.65 kg / 65.21 N Magnetic Induction 277.16 mT / 2772 Gs
Diameter
20 mm [±0,1 mm]
internal diameter Ø
8/4 mm [±0,1 mm]
Height
5 mm [±0,1 mm]
Weight
11.31 g
Magnetization Direction
↑ axial
Coating
[NiCuNi] Nickel

How we measure these parameters — certificates and measurements

view parameters »

6.30 zł net / pcs

7.75 zł with VAT (23% VAT) / pcs

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price from 1 pcs
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price from 100 pcs
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price from 400 pcs
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6.82 zł

Frequently asked questions

What is the hole in a ring magnet for?
For mounting on a screw or a shaft. The bore may be cylindrical or countersunk for a screw head. The hole removes magnet volume, so a ring holds less than a disc of the same outside diameter.
What is the polarisation?
Axial as standard — poles on the flat faces of the ring. Diametrical polarisation is made to order.
What sizes are available?
Outside diameter from 5 to 62 mm from stock. To order up to 200 mm outside diameter, 180 mm bore and 40 mm height, with a lead time of 25–35 days.

Guides from the knowledge base

Engineering report for this magnet

Full PDF analysis: pull and shear force, effect of distance, temperature and plate thickness, safety distances and the demagnetization curve.

PDF report Calculator
Want to talk magnets?

Call us now +48 888 99 98 98 alternatively let us know using contact form the contact section.
Specifications and structure of a neodymium magnet can be estimated using our power calculator.

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Technical of the product - MP 20x8/4x5 / N38 - ring magnet

Specification / characteristics - MP 20x8/4x5 / N38 - ring magnet

properties
properties values
Cat. no. 030333
GTIN/EAN 5906301812272
Production/Distribution Dhit sp. z o.o.
ul. Zielona 14 05-850 Ożarów Mazowiecki PL
Country of origin Poland / China / Germany
Customs code 85059029
Diameter 20 mm [±0,1 mm]
internal diameter Ø 8/4 mm [±0,1 mm]
Height 5 mm [±0,1 mm]
Weight 11.31 g
Magnetization Direction ↑ axial
Load capacity ~ ? 6.65 kg / 65.21 N
Magnetic Induction ~ ? 277.16 mT / 2772 Gs
Coating [NiCuNi] Nickel
Manufacturing Tolerance ±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 20x8/4x5 / N38 - ring magnet
properties values units
Remanence Br ? 12.2-12.6 kGs
Remanence Br ? 1220-1260 mT
Coercivity bHc ? 10.8-11.5 kOe
Coercivity bHc ? 860-915 kA/m
Intrinsic coercivity iHc ≥ 12 kOe
Intrinsic coercivity iHc ≥ 955 kA/m
Energy product BHmax ? 36-38 BH max MGOe
Energy product BHmax ? 287-303 BH max KJ/m
Maximum working temperature ? ≤ 80 °C

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C
properties values units
Vickers hardness ≥550 Hv
Density ≥7.4 g/cm3
Curie Temperature TC 310 °C
Curie Temperature TF 590 °F
Specific resistance 150 μΩ⋅cm
Bending strength 250 MPa
Compressive strength 1000~1100 MPa
Thermal expansion parallel (∥) to orientation (M) (3-4) x 10-6 °C-1
Thermal expansion perpendicular (⊥) to orientation (M) -(1-3) x 10-6 °C-1
Young's modulus 1.7 x 104 kg/mm²

Physical analysis of the assembly - technical parameters

The following information constitute the outcome of a mathematical analysis. Results were calculated on models for the material Nd2Fe14B. Operational parameters may deviate from the simulation results. Use these data as a preliminary roadmap for designers.

Table 1: Static force (pull vs distance) - power drop
MP 20x8/4x5 / N38

Distance (mm) Induction (Gauss) / mT Pull Force (kg/lbs/g/N) Risk Status
0 mm 2424 Gs
242.4 mT
 6.65 kg / 14.66 pounds
6650.0 g / 65.2 N
 strong
1 mm 2265 Gs
226.5 mT
 5.81 kg / 12.80 pounds
5807.9 g / 57.0 N
 strong
2 mm 2070 Gs
207.0 mT
 4.85 kg / 10.69 pounds
4851.0 g / 47.6 N
 strong
3 mm 1858 Gs
185.8 mT
 3.91 kg / 8.61 pounds
3906.5 g / 38.3 N
 strong
5 mm 1437 Gs
143.7 mT
 2.34 kg / 5.16 pounds
2338.7 g / 22.9 N
 strong
10 mm 691 Gs
69.1 mT
 0.54 kg / 1.19 pounds
540.5 g / 5.3 N
 low risk
15 mm 343 Gs
34.3 mT
 0.13 kg / 0.29 pounds
133.3 g / 1.3 N
 low risk
20 mm 186 Gs
18.6 mT
 0.04 kg / 0.09 pounds
39.3 g / 0.4 N
 low risk
30 mm 70 Gs
7.0 mT
 0.01 kg / 0.01 pounds
5.5 g / 0.1 N
 low risk
50 mm 18 Gs
1.8 mT
 0.00 kg / 0.00 pounds
0.4 g / 0.0 N
 low risk
Grip strength decreases drastically with every subsequent millimeter of spacing. Remember that even a microscopic distance (e.g., contamination, paint, dust) strongly weakens the grip. Magnetic products operate optimally at the point of direct contact; gap kills the force. Observe how flashily the load capacity drop, when the product does not adhere flatly to the steel surface. When calculating the assembly, discard additional spacers.

Table 2: Sliding hold (vertical surface)
MP 20x8/4x5 / N38

Distance (mm) Friction coefficient Pull Force (kg/lbs/g/N)
0 mm Stal (~0.2) 1.33 kg / 2.93 pounds
1330.0 g / 13.0 N
1 mm Stal (~0.2) 1.16 kg / 2.56 pounds
1162.0 g / 11.4 N
2 mm Stal (~0.2) 0.97 kg / 2.14 pounds
970.0 g / 9.5 N
3 mm Stal (~0.2) 0.78 kg / 1.72 pounds
782.0 g / 7.7 N
5 mm Stal (~0.2) 0.47 kg / 1.03 pounds
468.0 g / 4.6 N
10 mm Stal (~0.2) 0.11 kg / 0.24 pounds
108.0 g / 1.1 N
15 mm Stal (~0.2) 0.03 kg / 0.06 pounds
26.0 g / 0.3 N
20 mm Stal (~0.2) 0.01 kg / 0.02 pounds
8.0 g / 0.1 N
30 mm Stal (~0.2) 0.00 kg / 0.00 pounds
2.0 g / 0.0 N
50 mm Stal (~0.2) 0.00 kg / 0.00 pounds
0.0 g / 0.0 N
The following data indicates the approximate force required to start the sliding of the magnet vertically against a upright metal surface (assuming standard friction coefficient). The holding force varies with the air gap between the magnet and the metal.

Table 3: Vertical assembly (sliding) - vertical pull
MP 20x8/4x5 / N38

Surface type Friction coefficient / % Mocy Max load (kg/lbs/g/N)
Raw steel
µ = 0.3 30% Nominalnej Siły
2.00 kg / 4.40 pounds
1995.0 g / 19.6 N
Painted steel (standard)
µ = 0.2 20% Nominalnej Siły
1.33 kg / 2.93 pounds
1330.0 g / 13.0 N
Oily/slippery steel
µ = 0.1 10% Nominalnej Siły
0.67 kg / 1.47 pounds
665.0 g / 6.5 N
Magnet with anti-slip rubber
µ = 0.5 50% Nominalnej Siły
3.33 kg / 7.33 pounds
3325.0 g / 32.6 N
When hanging a holder on a upright wall (e.g., a board), it you can count on only approx. 20%-30% of its maximum pull force. Gravity as well as a low friction coefficient mean that magnets slide down easier than they pull off. Designing a hanger? Remember that the sliding force is much weaker than the perpendicular breakaway force. On a smooth steel, the holder will slide down under a much lighter cargo. Utilizing a rubberized layer can drastically raise the stability.

Table 4: Material efficiency (substrate influence) - sheet metal selection
MP 20x8/4x5 / N38

Steel thickness (mm) % power Real pull force (kg/lbs/g/N)
0.5 mm
10%
 0.67 kg / 1.47 pounds
665.0 g / 6.5 N
1 mm
25%
 1.66 kg / 3.67 pounds
1662.5 g / 16.3 N
2 mm
50%
 3.33 kg / 7.33 pounds
3325.0 g / 32.6 N
3 mm
75%
 4.99 kg / 11.00 pounds
4987.5 g / 48.9 N
5 mm
100%
 6.65 kg / 14.66 pounds
6650.0 g / 65.2 N
10 mm
100%
 6.65 kg / 14.66 pounds
6650.0 g / 65.2 N
11 mm
100%
 6.65 kg / 14.66 pounds
6650.0 g / 65.2 N
12 mm
100%
 6.65 kg / 14.66 pounds
6650.0 g / 65.2 N
A thin metal plate cannot focus the entire magnetic field, which squanders power of the holder. Should you mount a strong magnet to a too thin substrate, the field will penetrate right through and the holding will be smaller. To squeeze 100% of this magnet's potential, you need a suitably thick piece of metal. The saturation phenomenon means that on thin elements (e.g., car bodies), the magnet shows lower pull force. We suggest choosing the steel cross-section from these parameters.

Table 5: Thermal resistance (material behavior) - resistance threshold
MP 20x8/4x5 / N38

Ambient temp. (°C) Power loss Remaining pull (kg/lbs/g/N) Status
20 °C 0.0% 6.65 kg / 14.66 pounds
6650.0 g / 65.2 N
 OK
40 °C -2.2% 6.50 kg / 14.34 pounds
6503.7 g / 63.8 N
 OK
60 °C -4.4% 6.36 kg / 14.02 pounds
6357.4 g / 62.4 N
80 °C -6.6% 6.21 kg / 13.69 pounds
6211.1 g / 60.9 N
100 °C -28.8% 4.73 kg / 10.44 pounds
4734.8 g / 46.4 N
Standard neodymium magnets irreversibly lose parameters past the thermal threshold. Watch out for overheating – excessive heat can permanently destroy this product. With increasing heat, the magnet's force momentarily lowers. Refrain from using this product close to ovens exceeding its safe range. Exceeding the critical threshold will cause permanent loss of magnetism.
*Engineering note: Thermal stability is determined by both grade, but also on the magnet's shape. Low-profile magnets (low permeance coefficient) risk losing magnetic properties under lower heat stress than taller cylinders. Red status in the table signals permanent field degradation for this specific geometry.

Table 6: Two magnets (repulsion) - field range
MP 20x8/4x5 / N38

Gap (mm) Attraction (kg/lbs) (N-S) Shear Force (kg/lbs/g/N) Repulsion (kg/lbs) (N-N)
0 mm 9.28 kg / 20.47 pounds
4 012 Gs
1.39 kg / 3.07 pounds
1393 g / 13.7 N
 N/A
1 mm 8.73 kg / 19.25 pounds
4 701 Gs
1.31 kg / 2.89 pounds
1310 g / 12.8 N
 7.86 kg / 17.33 pounds
~0 Gs
2 mm 8.11 kg / 17.88 pounds
4 530 Gs
1.22 kg / 2.68 pounds
1216 g / 11.9 N
 7.30 kg / 16.09 pounds
~0 Gs
3 mm 7.45 kg / 16.42 pounds
4 342 Gs
1.12 kg / 2.46 pounds
1117 g / 11.0 N
 6.70 kg / 14.78 pounds
~0 Gs
5 mm 6.10 kg / 13.45 pounds
3 930 Gs
0.92 kg / 2.02 pounds
915 g / 9.0 N
 5.49 kg / 12.11 pounds
~0 Gs
10 mm 3.27 kg / 7.20 pounds
2 875 Gs
0.49 kg / 1.08 pounds
490 g / 4.8 N
 2.94 kg / 6.48 pounds
~0 Gs
20 mm 0.75 kg / 1.66 pounds
1 382 Gs
0.11 kg / 0.25 pounds
113 g / 1.1 N
 0.68 kg / 1.50 pounds
~0 Gs
50 mm 0.02 kg / 0.04 pounds
220 Gs
0.00 kg / 0.01 pounds
3 g / 0.0 N
 0.02 kg / 0.04 pounds
~0 Gs
60 mm 0.01 kg / 0.02 pounds
139 Gs
0.00 kg / 0.00 pounds
1 g / 0.0 N
 0.00 kg / 0.00 pounds
~0 Gs
70 mm 0.00 kg / 0.01 pounds
93 Gs
0.00 kg / 0.00 pounds
1 g / 0.0 N
 0.00 kg / 0.00 pounds
~0 Gs
80 mm 0.00 kg / 0.00 pounds
65 Gs
0.00 kg / 0.00 pounds
0 g / 0.0 N
 0.00 kg / 0.00 pounds
~0 Gs
90 mm 0.00 kg / 0.00 pounds
47 Gs
0.00 kg / 0.00 pounds
0 g / 0.0 N
 0.00 kg / 0.00 pounds
~0 Gs
100 mm 0.00 kg / 0.00 pounds
35 Gs
0.00 kg / 0.00 pounds
0 g / 0.0 N
 0.00 kg / 0.00 pounds
~0 Gs
Two magnetic products attract each other from a significantly greater distance than a neodymium and metal setup. The connection of two magnets generates a stronger field and a larger range of performance. Planning to create a strong closure? Use a pair of magnets instead of one magnet and a steel. Remember that when attracting two neodymiums, the pinch force is huge. The levitation is slightly lower than the attraction, but still significant.
*The magnetic induction for N-N configuration reaches ~0 Gs in the exact middle of the gap (caused by magnetic field nullification).
Attention: Estimates refer to shear force of dual same neodymium magnets (friction coefficient ~0.15 for Ni-Ni layer).

Table 7: Hazards (electronics) - warnings
MP 20x8/4x5 / N38

Object / Device Limit (Gauss) / mT Safe distance
Pacemaker 5 Gs (0.5 mT) 8.0 cm
Hearing aid 10 Gs (1.0 mT) 6.5 cm
Timepiece 20 Gs (2.0 mT) 5.0 cm
Mobile device 40 Gs (4.0 mT) 4.0 cm
Remote 50 Gs (5.0 mT) 3.5 cm
Payment card 400 Gs (40.0 mT) 1.5 cm
HDD hard drive 600 Gs (60.0 mT) 1.5 cm
Powerful magnet radiation poses a serious hazard to electronics and pacemakers. These neodymiums generate a field that prevents correct functioning of sensitive medical devices. Be aware: the unseen radiation acts through matter and glass. Increased vigilance must be exercised by people with hearing aids and insulin pumps. The risk also applies to: mechanical watches, car keys, membranes, and screens. Avoid contact with magnetic cards, hard drives, or sensitive navigation tools.

Table 8: Dynamics (cracking risk) - warning
MP 20x8/4x5 / N38

Start from (mm) Speed (km/h) Energy (J) Predicted outcome
10 mm 25.22 km/h
(7.01 m/s)
 0.28 J
30 mm 26.09 km/h
(7.25 m/s)
 0.30 J
50 mm 26.10 km/h
(7.25 m/s)
 0.30 J
100 mm 26.11 km/h
(7.25 m/s)
 0.30 J
Neodymium magnets are delicate – a strong collision with metal risks their cracking. Control the attraction moment – a magnet released freely turns into a projectile. Striking energy can cause material chips or injury to skin. Be sure to control the product during mounting so it doesn't hit with great force against the metal. A contact at a velocity of dozens of km/h almost guarantees destruction of the neodymium. Use safety goggles when working with powerful specimens.

Table 9: Corrosion resistance
MP 20x8/4x5 / N38

Technical parameter Value / Description
Coating type [NiCuNi] Nickel
Layer structure Nickel - Copper - Nickel
Layer thickness 10-20 µm
Salt spray test (SST) ? 24 h
Recommended environment Indoors only (dry)
The following table defines the conditions under which this product can be safely used. Moisture resistance is crucial for installations in bathrooms or outdoors.

Table 10: Construction data (Pc)
MP 20x8/4x5 / N38

Parameter Value SI Unit / Description
Magnetic Flux 7 218 Mx 72.2 µWb
Pc Coefficient 0.31 Low (Flat)
Total magnetic flux passing through the pole surface. Key data for generator designers as well as sensors. Pc value determines the working geometry.

Table 11: Hydrostatics and buoyancy
MP 20x8/4x5 / N38

Environment Effective steel pull Effect
Air (land) 6.65 kg Standard
Water (riverbed) 7.61 kg
(+0.96 kg buoyancy gain)
+14.5%
Rust risk: Standard nickel requires drying after every contact with moisture; lack of maintenance will lead to rust spots.
In water, the magnet feels stronger thanks to Archimedes' principle. As a result, your magnet will pull a heavier object from the bottom than if you lifted it in the air.

1. Wall mount (shear)

*Note: On a vertical surface, the magnet retains merely approx. 20-30% of its max power.

2. Plate thickness effect

*Thin steel (e.g. 0.5mm PC case) severely reduces the holding force.

3. Heat tolerance

*For standard magnets, the safety limit is 80°C.

4. Demagnetization curve and operating point (B-H)

chart generated for the permeance coefficient Pc (Permeance Coefficient) = 0.31

The chart above illustrates the magnetic characteristics of the material within the second quadrant of the hysteresis loop. The solid red line represents the demagnetization curve (material potential), while the dashed blue line is the load line based on the magnet's geometry. The Pc (Permeance Coefficient), also known as the load line slope, is a dimensionless value that describes the relationship between the magnet's shape and its magnetic stability. The intersection of these two lines (the black dot) is the operating point — it determines the actual magnetic flux density generated by the magnet in this specific configuration. A higher Pc value means the magnet is more 'slender' (tall relative to its area), resulting in a higher operating point and better resistance to irreversible demagnetization caused by external fields or temperature. A value of 0.42 is relatively low (typical for flat magnets), meaning the operating point is closer to the 'knee' of the curve — caution is advised when operating at temperatures near the maximum limit to avoid strength loss.

Engineering data and GPSR

Elemental analysis

iron (Fe) 64% – 68%
neodymium (Nd) 29% – 32%
boron (B) 1.1% – 1.2%
dysprosium (Dy) 0.5% – 2.0%
coating (Ni-Cu-Ni) < 0.05%

Ecology and recycling (GPSR)

recyclability (EoL) 100%
recycled raw materials ~10% (pre-cons)
carbon footprint low / zredukowany
waste code (EWC) 16 02 16
Safety card (GPSR)
responsible entity
Dhit sp. z o.o.
ul. Kościuszki 6A, 05-850 Ożarów Mazowiecki
tel: +48 22 499 98 98 | e-mail: bok@dhit.pl
batch number/type
id: 030333-2026
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It is ideally suited for places where solid attachment of the magnet to the substrate is required without the risk of detachment. Thanks to the hole (often for a screw), this model enables easy screwing to wood, wall, plastic, or metal. This product with a force of 6.65 kg works great as a cabinet closure, speaker holder, or spacer element in devices.
This is a crucial issue when working with model MP 20x8/4x5 / N38. Neodymium magnets are sintered ceramics, which means they are hard but breakable and inelastic. One turn too many can destroy the magnet, so do it slowly. It's a good idea to use a rubber spacer under the screw head, which will cushion the stresses. Remember: cracking during assembly results from material properties, not a product defect.
Moisture can penetrate micro-cracks in the coating and cause oxidation of the magnet. Damage to the protective layer during assembly is the most common cause of rusting. If you must use it outside, paint it with anti-corrosion paint after mounting.
A screw or bolt with a thread diameter smaller than 8/4 mm fits this model. If the magnet does not have a chamfer (cone), we recommend using a screw with a flat or cylindrical head, or possibly using a washer. Aesthetic mounting requires selecting the appropriate head size.
It is a magnetic ring with a diameter of 20 mm and thickness 5 mm. The pulling force of this model is an impressive 6.65 kg, which translates to 65.21 N in newtons. The product has a [NiCuNi] coating and is made of NdFeB material. Inner hole dimension: 8/4 mm.
The poles are located on the planes with holes, not on the sides of the ring. If you want two such magnets screwed with cones facing each other (faces) to attract, you must connect them with opposite poles (N to S). We do not offer paired sets with marked poles in this category, but they are easy to match manually.

Strengths and weaknesses of Nd2Fe14B magnets.

Advantages

Besides their high retention, neodymium magnets are valued for these benefits:
  • They virtually do not lose power, because even after ten years the performance loss is only ~1% (according to literature),
  • They retain their magnetic properties even under strong external field,
  • A magnet with a metallic gold surface is more attractive,
  • The surface of neodymium magnets generates a maximum magnetic field – this is one of their assets,
  • Through (adequate) combination of ingredients, they can achieve high thermal resistance, enabling action at temperatures approaching 230°C and above...
  • Thanks to the option of precise forming and customization to specialized solutions, magnetic components can be produced in a broad palette of geometric configurations, which increases their versatility,
  • Versatile presence in electronics industry – they serve a role in mass storage devices, brushless drives, precision medical tools, as well as other advanced devices.
  • Compactness – despite small sizes they generate large force, making them ideal for precision applications

Cons

Cons of neodymium magnets: weaknesses and usage proposals
  • Brittleness is one of their disadvantages. Upon intense impact they can fracture. We advise keeping them in a strong case, which not only protects them against impacts but also increases their durability
  • When exposed to high temperature, neodymium magnets experience a drop in power. Often, when the temperature exceeds 80°C, their power decreases (depending on the size, as well as shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
  • Due to the susceptibility of magnets to corrosion in a humid environment, we recommend using waterproof magnets made of rubber, plastic or other material stable to moisture, in case of application outdoors
  • Due to limitations in realizing nuts and complex forms in magnets, we propose using a housing - magnetic mount.
  • Possible danger resulting from small fragments of magnets are risky, when accidentally swallowed, which gains importance in the aspect of protecting the youngest. It is also worth noting that small components of these products can disrupt the diagnostic process medical when they are in the body.
  • Due to complex production process, their price is relatively high,

Holding force characteristics

Detachment force of the magnet in optimal conditions – what it depends on?

The force parameter is a theoretical maximum value conducted under the following configuration:
  • using a sheet made of high-permeability steel, functioning as a circuit closing element
  • with a cross-section no less than 10 mm
  • with a plane free of scratches
  • without any air gap between the magnet and steel
  • during detachment in a direction perpendicular to the mounting surface
  • at temperature room level

Practical aspects of lifting capacity – factors

During everyday use, the real power is determined by a number of factors, presented from most significant:
  • Distance – existence of any layer (rust, dirt, air) acts as an insulator, which lowers power steeply (even by 50% at 0.5 mm).
  • Load vector – highest force is obtained only during perpendicular pulling. The resistance to sliding of the magnet along the surface is typically many times lower (approx. 1/5 of the lifting capacity).
  • Wall thickness – thin material does not allow full use of the magnet. Part of the magnetic field penetrates through instead of converting into lifting capacity.
  • Material type – the best choice is high-permeability steel. Hardened steels may attract less.
  • Surface condition – ground elements guarantee perfect abutment, which increases force. Uneven metal weaken the grip.
  • Temperature influence – high temperature weakens magnetic field. Exceeding the limit temperature can permanently damage the magnet.

Lifting capacity was measured with the use of a polished steel plate of optimal thickness (min. 20 mm), under perpendicular pulling force, whereas under shearing force the load capacity is reduced by as much as 5 times. Additionally, even a slight gap between the magnet and the plate decreases the holding force.

H&S for magnets
Bone fractures

Risk of injury: The pulling power is so immense that it can result in hematomas, pinching, and even bone fractures. Protective gloves are recommended.

This is not a toy

Only for adults. Tiny parts can be swallowed, leading to severe trauma. Keep away from children and animals.

Beware of splinters

NdFeB magnets are sintered ceramics, which means they are fragile like glass. Clashing of two magnets will cause them shattering into shards.

Skin irritation risks

Medical facts indicate that the nickel plating (the usual finish) is a strong allergen. If your skin reacts to metals, avoid touching magnets with bare hands and select encased magnets.

Electronic hazard

Avoid bringing magnets near a purse, laptop, or screen. The magnetism can irreversibly ruin these devices and erase data from cards.

Medical implants

People with a ICD should maintain an large gap from magnets. The magnetic field can disrupt the functioning of the implant.

Demagnetization risk

Monitor thermal conditions. Heating the magnet above 80 degrees Celsius will ruin its properties and pulling force.

Immense force

Before use, read the rules. Sudden snapping can destroy the magnet or injure your hand. Be predictive.

Do not drill into magnets

Dust generated during grinding of magnets is flammable. Do not drill into magnets unless you are an expert.

Phone sensors

An intense magnetic field disrupts the operation of compasses in smartphones and navigation systems. Maintain magnets close to a device to avoid breaking the sensors.

Safety First! Learn more about risks in the article: Safety of working with magnets.