The first industrial metal detectors were developed in the 1960s and were used extensively for mineral prospecting and other industrial applications. Uses include detecting land mines, the detection of weapons such as knives and guns (especially in airport security), geophysical prospecting, archaeology and treasure hunting. Metal detectors are also used to detect foreign bodies in food, and in the construction industry to detect steel reinforcing bars in concrete and pipes and wires buried in walls and floors.
The simplest form of a metal detector consists of an oscillator producing an alternating current that passes through a coil producing an alternating magnetic field. If a piece of electrically conductive metal is close to the coil, eddy currents will be induced in the metal, and this produces a magnetic field of its own. If another coil is used to measure the magnetic field (acting as a magnetometer), the change in the magnetic field due to the metallic object can be detected.
Use this coaster to house your favourite drink.
This is a standard size coaster (100 by 100 by 5 mm), to fit in my coasterholder:
I have printed this model with Ultimaker white PLA. I used 0.2mm layer height and, 18% infill. I used a 0.4mm nozzle with my extruder at 210 degrees Celcius. I used a heated bed. To avoid the curling up at the bottom i used a brim. Don't hesitate to use your own configuration....no worries!
I picked a logo from my browser and have put it in svg format in inktscape. Opened the svg file in blender and made it a 3D object. In meshmixer i have repaired the file; and erased some aspects. In meshmixer i have also added a coaster. Than i have merged the coaster with the picture after scaling the picture. Saved it as a STL file and sliced it for printing. Cause the model has still some issues even after repairing it in meshmixer; i have decided to export it into Netfabb Online Service. This is an app i discovered recently after using MakePrintable. Cause MakePrintable in my opion only gives us 3 procedures of fixing an STL file and, with Netfabb Online Service the frequency of STL fix procedures is unlimited, my choice was clear. It worked well for me and i could slice the model without any problems.
If you would like to know how i design a 2D picture (google) into a 3D model. Use this link:
https://www.youtube.com/watch?v=g6cmClwLhz8 (video is under 6 min.)
2D to 3D in Blender
use this link to download blender for free: https://www.blender.org/download/
use this link to download inkscape for free: https://inkscape.org/nl/download/