FAQ - Frequently Asked Questions (and their answers!)
Do you have a x gauss magnet?
We often receive such questions from customers who read a book about the healing power of magnets and who are now looking for a suitable magnet.
We don't believe in a healing power of magnets that goes beyond the placebo effect, but we generally agree that you don't have to purchase an over-priced "healing magnet" for your own experiments. A simple and affordable neodymium magnet will do, since it's the same type of magnet.
The question doesn't have a simple answer. It's like asking "Do you have a lamp that is bright enough to read a book with?" You can do that with nearly every lamp if you hold the book close enough. But are you able to read your book at a distance of 5 metres or 10 metres? That depends on the illuminating power of the lamp. The same holds true for magnets.
Just like the brightness of a lamp, also the magnetic flux density (the gauss number) of a magnet decreases with increasing distance.
Therefore, the question should be: "Do you have a magnet that produces a magnetic flux density of 800 gauss at a distance of 20 mm from the surface?"
Actually, most of our magnets, even the smallest ones, have several 1000 gauss directly at the surface. Depending on the form and strength of the magnetisation, it's possible that a certain magnet only produces 100 gauss at a distance of 10 mm, while another might still produce 2000 gauss.
The magnetic field is the strongest directly on the surface on the edge of the pole faces (block magnets at the corners) and the weakest in the centre.
However, the field decreases much faster with increasing distance from the magnet around the edge than the field on the central magnetic axis. Even a few millimetres away might make the field on the axis stronger than the one around the edge. (See also the tables below.)
Some manufacturers and sellers specify gauss numbers on their magnets that can only be reached when the magnet is being "short-circuited" by an iron yoke and only a tiny air gap between north and south pole remains. Such a hypothetical value cannot be reached on the surface and even less outside a freestanding magnet.
Since you normally can't bring the magnet all the way to the spot that needs treatment, you have to decide at which distance the magnet should be effective. Then we can calculate which size magnet is necessary to reach the desired result.
It's a little difficult to calculate the value yourself, because it is a complicated formula (see FAQ: How do you calculate the magnetic flux density?.
Conversion: 1 Tesla = 10'000 Gauss
Here a few examples. Maybe this helps you find a suitable magnet. If not, please don't hesitate to contact us.
Gauss numbers on the magnetic axis (= straight line through the centres of the pole faces):
| Distance | 0mm | 5 mm | 10 mm | 20 mm | Unit |
|---|---|---|---|---|---|
| S-06-02-N | 3200 | 360 | 80 | 10 | Gauss |
| S-10-03-N | 3000 | 800 | 230 | 40 | Gauss |
| S-20-05-N | 2600 | 1500 | 750 | 200 | Gauss |
| S-20-10-N | 4100 | 2200 | 1000 | 300 | Gauss |
| S-45-30-N | 4800 | 3700 | 2800 | 1500 | Gauss |
| Q-20-20-03-N | 1600 | 1100 | 600 | 200 | Gauss |
Gauss numbers on the edge (= on a straight line parallel to the magnetic axis through the edge):
| Distance | 0mm | 5 mm | 10 mm | 20 mm | Unit |
|---|---|---|---|---|---|
| S-06-02-N | 6800 | 280 | 70 | 10 | Gauss |
| S-10-03-N | 7600 | 560 | 180 | 40 | Gauss |
| S-20-05-N | 8800 | 1100 | 490 | 160 | Gauss |
| S-20-10-N | 8400 | 1600 | 760 | 250 | Gauss |
| S-45-30-N | 10800 | 3100 | 2000 | 1000 | Gauss |
| Q-20-20-03-N | 3900 | 500 | 250 | 90 | Gauss |
