DIY 3D Printed 120mm Fume Extractor

Do you need to do wire soldering often? Maybe you like making artworks with your pirography tool, or painting your creations with an airbrush. In all these cases, and many others, having a practical, beautiful, and simple fume extractor can make the difference between good and bad air quality.

This extractor has been designed from scratch in order to allow using an high airflow 120mm fan, which will be more than enough for any kind of application, and couples the air funneling power with a cleaning effect given by the carbon filters stored in front of the fan.

This project pairs 3d printing with simple soldering: don't worry if you are not an expert, each step is very detailed to help new people starting their diy journey!

The 3D printing process is detailed with tips and warnings where needed on the dedicated thingiverse page!

I suggest you to read the article fully before buying supplies and starting it, as there may be details that are important to know beforehand!

Here is a list of the tools you will need for this project:

• M3 Allen wrench or screwdriver bit
• Philips screwdriver bit
• Soldering iron and tin
• Hobby knife/scissor/wire cutter (preferred)
• (optional) two color markers, to be used for marking positive and negative wires
• Multimeter
• Lighter (for the heat shrinking tube)
• Superglue

Here is a list of all the hardware that you will need

• High airflow (CFM) 120mm 12V fan, I personally used this one as it has a ridiculous 200CFM and comes with an integrated fan grill120mm
• Fan grill if it doesn't come with your fan
• 2x 12.8x12.8 activated carbon filter (aliexpress)
• 12v power supply (aliexpress)
• 10x15 switch (aliexpress)
• 470 ohm resistor (aliexpress)
• Led light (aliexpress)
• 12v female socket (aliexpress)
• 8x m3 square nuts (aliexpress)
• Mini DC speed controller (aliexpress)
• 8x m3x12 bolts
• Heat shrinking tube

As you will see in this instructables, I like to test everything out step by step, and nothing ensures the best odds of success than having the entire circuit built beforehand!

As you can see in the schematic, this is a relatively simple circuit, composed of a DC input which will power our fan. To show that the circuit is being powered, we have an LED light, and to allow toggling the circuit on or off, we have a simple switch. As the fan is too powerful at full speed, we have a DC voltage regulator, which allows to take the input 12V and turn it down to our liking.

If you want to test everything out like I did, you can check my breadboard implementation. At this step, nothing needs to be soldered, as you will need to take everything apart again.

How can we have a fume extractor without an enclosure? We can't, and that's why this would be a good time to power on your 3D printer and melt some filament!

Get to the thingiverse page of this project, download all the files, read all the description, and come back when your enclosure is ready to be assembled.

All the lids that you will assemble have two sides: you can recognize them by looking at the screw holes. The side that has a larger hole will accommodate the bolt head, so it will need to go outside. Keep this in mind when attaching components to the lids as you may have to de-solder and take them off just because of an overlook.

First of all, I decided to start assembling the back lid, which namely houses the female DC connector. This will allow us to test all the new components we will attach, by using actual current to power them.

Insert the DC connector in the lid hole and screw the nut to hold it in place.

You may notice that the female connector has 3 pins to solder your wires to, but you will have to use only two wires:

If you fully tested your circuit beforehand you had to figure this out already, good.

Otherwise, take out your multimeter and put it in DC mode, connect the DC power supply to the connector and test the poles two by two. Once you get a reading of 12 volts, that means that your red probe is on the positive pin, and the black probe is on the negative one. You can clip out the third pin to ease your work, and optionally mark each pole with the two markers so you avoid mistaking it.

Now, what I did was dry-assembling the extractor in order to check the length of wire that should go from the fan to the front lid, leave some more for good measure, and cut the excess off. The removed wire will be used to connect the various components, starting from this connector.

Lastly, if you want to be extra fancy, you can add sections of heat shrinking tubes for each soldered cable you do, and a bigger section that covers group of cables that should stay together.

Now for the front lid, the hearth of the fume extractor:

• Insert the led in the led hole, and superglue it so it doesn't pop out in the future
• note which led leg is the positive one, in this case the longer one, and solder one side of the resistor to it. Solder a small wire section to the negative side
• insert the switch into his housing (make sure to insert it the right way, as it's difficult to remove after it's set)
• solder the positive wire coming from the DC adapter to one switch pin, and solder the resistor to the other switch pin. You can already couple the resistor with a second wire, as it will be needed later
• simply twist the led negative wire with the dc negative wire, so you can test if the switch+resistor+led combo works
• finally, place the voltage regulator on its designated hole and lock it with its provided nut

If you want to be extra sure, first twist the wires by hand and test the circuit, and then solder everything down, as I did in picture 1

now that the led works, connect the positive wire coming from the switch to the DC IN + terminal on the voltage regulator, and the negative wire coming from the led + the one coming from the power supply to the DC IN - terminal. The voltage regulator should light up, and if so, connect the positive and negative wires from the fan (passing through the built in hole on the bottom of the shell side) to the MOTOR OUT + and - terminals.

Test again! The fan should start to spin when the power supply is connected, the switch in the ON state, and the regulator on a working position. My voltage regulator clicks and cuts off the power of the fan when turned all the way counterclockwise, but I wanted to still have the switch circuit in place as it will allow the user to turn on the fan at a specific speed if the regulator is left untouched after shutting down the extractor.

The hard part is completed! Now it's time to put this bad boy together. The way I designed it is having lids working as structural elements that keep the frame in place, as each lid will securely connect to the shell using the M3 bolts and square nuts. Check the shells, there are a total of 8 slots to insert the nuts in.

Start off by aligning the two half shells, and screwing in the back lid first followed by the front lid. The fan will need to be secured together with the fan grill, which you will mount on the outside.

Insert two carbon filters in their designated slot in front of the fan, and then screw the top lids on the shell.

!ATTENTION!

As you can see in the pictures, my fan grill is held in place with 4 bolts and washers: this is because the provided screws won't go all the way to the fan when used on the extractor, so I just superglued 4 nuts on the internal side (where the holes are), and used them to secure the bolts when threaded in.

You now have a fully functional, professional, aircraft grade, fume extractor. And you built it yourself!

Congratulate with yourself, set something on fire, and suck all the fumes away thanks to your new creation!