Button magnet is very convenient when we want to attach our circuit boards or any not so heavy boxes to some metal surfaces.

I was working on a project in which a PCB containing coil tracks has to be attached to the rotor disk of a motor inorder to test the inducive sensor used for measureing the speed or the rotor. We have designed the PCB such that the it can be attached to rotor disk using a magnet.

But there was a problem, we dont have a suitable magnet. Lot of vendors are available online, but they will take some time for the order to be delivered. So I went searhing in the hardware shops around Kanthaswamy temple, near pookkada, parrys market for a button magnet. In the hardware shops only black ferrite magnets were available. After searching a lot i got the shining neyodymium magnet from a toy distributor shop. There was only one type available(10mm dia x 1mm thickness) and it was perfect for our requirement.