Magnets for inspection hatches
Short answer: attach an inspection hatch or service panel magnetically with magnets on the hatch and a steel strip, plate, or counter-magnet in the frame. On a steel frame, pot magnets with a countersunk hole are sufficient; in wood or plastic, use magnets with a countersunk hole with a counter-magnet. Allow for 2 to 4 magnets per hatch. Secure hatches above the head (ceiling) additionally with a safety cable.
Which magnets for which hatch?
| Hatch | Recommendation |
|---|---|
| Small hatch in a cabinet or wall (up to 40 x 40 cm) | 2 magnets with countersunk hole Ø15 – Ø20 mm + steel plates or counter-magnets |
| Service panel in a machine (steel frame) | 4 pot magnets with countersunk hole Ø16 – Ø25 mm; see magnets for machine building |
| Lacquered hatch or panel | rubber pot magnets or a rubber protective disc |
| Light plastic cover plate | self-adhesive magnets with a steel counter-plate |
| Ceiling hatch | pot magnets loaded perpendicularly, plus a safety cable |
Allow for 2 to 4 magnets per hatch
- Hatch in wood or plastic, magnet against magnet: combine the north pole- and south pole variant of the block magnet 30 x 13.5 x 5 mm (approx. 5.2 kg each).
- Hatch in wood or plastic, magnet against steel: ring magnet Ø20 mm with countersunk hole (approx. 2.1 kg) with a steel counter-ring Ø20 mm in the frame.
- Service panel on a steel frame: pot magnet Ø16 x 5 mm with countersunk hole (approx. 7.3 kg), or for larger panels the pot magnet Ø25 mm with countersunk hole.
Ceiling hatch? Always secure it additionally with a safety cable.
Design tips
- Perpendicular is stronger: a hatch that lies in a recess is pulled perpendicularly by the magnets and rests on the edge. That is much stronger than a panel that hangs on a vertical wall.
- Handle: give the hatch a handle or a recess to pull it loose, otherwise it will be difficult to remove.
- North and south: with magnet against magnet you need a north pole and a south pole variant. We offer these separately for a number of magnets with countersunk holes.
- Not too strong: a hatch that closes too hard damages the edge. Test with 2 magnets before placing more.
Frequently asked questions
How much holding force does an inspection hatch need?
For a wall hatch, 2 – 5 kg per magnet is usually enough; for a ceiling hatch, allow for 3 times the weight of the hatch, plus securing. See how many magnets do I need?
Does it work through drywall or a wooden frame?
Yes, with two magnets (one on each side) or a magnet with a steel plate. The force decreases with thickness; see do magnets work through wood?
