Which magnet should I choose?
Short answer: choose a magnet in this order: (1) what must it attach to: steel or a second magnet; (2) how will you mount it: screwing, gluing, sticking or clamping; that determines the shape; (3) how much force do you need: allow a margin of 2 to 3 times, on a vertical wall 5 to 10 times; (4) indoors or outdoors: that determines the coating; (5) will it get hotter than 80 °C. Choose the N grade (N35 – N52) last: size matters more.
Step 1: what must the magnet attach to?
- To steel (cabinet, beam, plate): one magnet is enough. On thick steel a pot magnet is the strongest.
- To another magnet (closure, lid, model making): use two magnets with opposite poles, or a magnet with a steel counter plate.
- Through a material (wood, glass, fabric): choose a thicker magnet. See do magnets work through wood, glass and plastic?
- On aluminium or stainless steel: does not work. Stick or screw a steel plate on first.
Step 2: how will you mount it? That determines the shape
| Mounting | Best shape | Selection guide |
|---|---|---|
| Gluing into a round hole | disc magnet | which disc magnet? |
| In a slot or on a straight edge | block magnet | which block magnet? |
| Screwing | countersunk or ring magnet | which ring magnet? |
| Deep installation, narrow hole | rod magnet | which rod magnet? |
| Fixing with a bolt, hook or eye | pot magnet | which pot magnet? |
| Hanging | hook or eye magnet | hook / eye |
| Sticking on a smooth surface | self-adhesive magnet | self-adhesive magnets |
| Sewing into fabric | sew-in magnet with PVC | sew-in magnets |
| Building, puzzles, memo board | cube or ball magnet | cube / ball |
An overview of all shapes is in which neodymium magnet should you choose? Overview per shape.
Step 3: how much holding force do you need?
- Pulling perpendicularly on thick steel: choose a magnet with a stated holding force of at least 2 to 3 times the weight.
- On a vertical wall or door: the magnet already slides at 15 – 25% of its holding force. Choose 5 to 10 times the weight, or a rubber version.
- Through paint, film or wood: allow even more; see the table in do magnets work through wood?
- Closure (small door, lid): 0.5 – 2 kg per closure is usually enough. Too strong is not good either: then it is hard to open.
A table with holding force per size is in how strong is a neodymium magnet? Note: holding force is not a working load. See holding force, pull force and working load.
Step 4: indoors, damp or outdoors?
- Indoors, dry: standard NiCuNi coating.
- Damp or sheltered outdoors: epoxy.
- Outdoors in the rain: plastic-coated.
- On paintwork: rubber.
More in can magnets be used outdoors?
Step 5: temperature
Standard neodymium can withstand up to approx. 80 °C (N50 and N52 up to approx. 60 – 70 °C). Near lamps, motors or in a car in the sun it can get hotter. See magnets at high temperatures.
Step 6: only then the grade
N45 to N48 is a good standard. N50/N52 when space is limited; N35 when price matters more than size. See what do N35, N42, N48 and N52 mean?
Frequently asked questions
What is the best magnet for a cabinet door?
Two disc magnets Ø8 x 3 mm or Ø10 x 3 mm (approx. 1.4 – 1.6 kg), or a magnet with a steel counter plate. With a countersunk hole you can screw them in place.
What is the best magnet for hanging something from a steel beam?
A hook or eye magnet. Choose generously: a pot magnet loaded sideways already slides at a quarter of its holding force.
Can I ask for advice?
Yes. Use the Magnet Advisor or contact us with your application, the dimensions and the weight.
