A couple of days I started making my own DIY solder fume smock remover, while I was testing it I came across a big problem at least for me the, the device wen powered on it makes a lot of noise.
I started looking for solutions for to solve the problem, I ended up with a simple plan to turn on the fans when the soldering iron is near and turning off the fans when the soldering iron is not close.
My best option to achieve the goal is to make an inductance meter with a large coil that acts as a metal detector, when the soldering iron enters the magnetic field of the coil it will increase its inductance, and that is picked up by the Arduino working as an Inductance Meter, when this increase reaches a certain threshold the Arduino will trigger the fans until the inductance being measured lowers to the normal value.
***Thins is an ongoing project so I have some bugs that needs some ironing like false triggering, and the apparent luck of a smock filter***
updated the code to be more efficient and removed the mathematical calculations that were slowing down the arduino.
Added new functionality that allows the coil to be connected to an external driving transistor instead of the Arduino GPIO pin, and the transistor type can be selected in the code.
The inductor is the part that is responsible of detecting the presence of the soldering Iron or any king of ferrous metal that enters its field.
The inductor is built around a 12Cm x 17Cm path. The inductor coil is held in place by four Crackers as shows in the images above.
2
Bolt down the Fans
Using four screws tight down the two fans to the side of the wood board
3
Wire up Everything
The control board is based on the Arduino Nano. This board contains all the necessary hardware for power regulation and Fan switching. Please see the circuit above to get in touch with all the connections. The board is little junky because it was built the hold an Esp32-can to run a ML code to recognize the soldering iron using a camera “I accidentally burned it”