It’s a device that senses magnetic fields in ... platform of the printer in three dimensions. Yes, it will create an image of field lines coming out of a magnet, but it’s a very slow process.

A flower-shaped structure only a few micrometers in size made of a nickel-iron alloy can concentrate and locally enhance ...

(Hardware and electronics stores sell them) Optional: Straight, plastic pipe of similar dimensions ... response to the moving magnetic field of the falling neodymium magnet. That eddy current ...