Magnets - Combine Flux Density, or Not?

[indieFan]

You don't give any specifics about the magnets: material, shape, coated or non-coated (coated = plated), direction of measurement, distance from measuring device, and what the magnetizing parameters are.

In my (short) experience which is measuring, not calculating the theoretical values, the biggest influences on the flux density are the coating (if any), the shape, and the distance from the measuring device.

The coating and the distance from the measuring device go together. Coating magnets (esp. small ones) leave them with rounded edges thereby raising the magnet away from the measuring device. Coating may also leave the magnet at an angle within the coating depending on the method of coating. The thickness of the coating may not be the same from magnet to magnet.

As for the shape, any chips or breaks will affect how the flux density travels around the magnet, thus changing it's measurement due to what the curves look like that are hitting the measuring device.

When magnets are measured on a point and then rotated,there isn't much variation within themselves depending on what your application is. When a magnet is moved horizontally across the measuring device and then graphed, the results are a (proper term is escaping me right now) cone with a rounded top. The flatness of the top gets larger the farther away from the measuring device you are.

That may not help a lot, but it's a little more food for thought.

indieFan