Soldering Fumes Extractor

Hi, I am Giovanni Aggiustatutto and I am passionate about electronics, DIY and home automation. In today's guide I will show you how I made an extractor for soldering iron fumes. In fact, if you do electronics projects or with Arduino, at some point you will need to do some soldering. I use the soldering iron in almost all of my projects, either to mount components on a board or to connect wires together. You will surely have noticed that the soldering iron produces some fumes, which are certainly not particularly healthy to breathe. So, I decided to build an extractor for the fumes that are produced by the soldering iron, which is also capable of filtering them with an activated carbon filter. This project is quite simple and inexpensive, and in my opinion it is also very useful.

As always, I've also made a video about this project, that you can find on my YouTube channel (it has English subtitles).

For this project I used:

• A high power 12V 10W 120x120x38 mm fan (Amazon: https://amzn.eu/d/hM4KwZk)
• An activated carbon filter sheet, made for kitchen hoods (Amazon: https://amzn.eu/d/blpe5Jc)
• 12V 2A power supply
• 20x10 mm aluminium profile
• 2 M6x30 mm hexagonal bolts
• 4 M6 nuts
• 2 M6 bolts with round head
• 8 M3x20 mm bolts
• 8 M3 threaded inserts
• Barrel DC connector
• Blue LED with 1K resistor
• Switch
• 2-pin microphone cable

Tools I used for this project:

• 3D printer with black and orange PLA filament
• Soldering iron
• Hot glue
• Drill press with 6 mm metal bit
• Metal saw
• Metal file
• Screwdrivers, pliers and other basic tools

This project has already been done by others in many variations, but all of them in my opinion have a problem: generally makers use PC fans in order to remove the soldering iron fumes, but they are not powerful enough. Due to this the fume extractor has to be very close to the area where we are soldering, making it inconvenient to use, and in the end, we end up never using it. For this reason for my fume extractor I bought a very powerful fan, that is able to remove the soldering fumes even if the extractor is around 30 cm from the soldering iron. Of course, the fact that the fan is very powerful also means that it is far more noisy than a PC fan, so that is something that needs to be taken into account. The fan runs on 12V, and having a power of 10W consumes about 800 mA.

The base idea behind this project is very simple: we need a frame for mounting the filter in front of the fan, and a base to raise it up from the table. However, I like to take great care of the aesthetics and design of my projects. So I spent some time designing on Fusion 360 the various parts with which I will build the fume extractor, to make it resemble a professional tool. I 3D printed all the parts, using black and orange PLA, following the color scheme of Black&Decker tools. The STL files for 3D printing are below.

The parts that need to be 3D printed include the box in which the fan will be placed, the base, in which the power switch will be put, and its cover. I also printed the two grids that will be used to mount the filter, a small border and other parts, including two knobs, four feet and two spacers.

Before mounting the fan in its enclosure, we need to think about the electrical cable that will connect it to the base, where the power switch will be. We could leave the original two wires from the fan, but in my opinion the look of them is a bit too thin and they do not fit well the design. So I cut the positive (red) and negative (black) wires of the fan quite short and soldered them to the two wires of a microphone audio cable, which is thicker and therefore in my opinion adds something to the final aesthetics. It is important to note here that I chose that cable just because I had it lying around, but every thick cable with at least two pins should work fine. I protected the soldering with heat shrink tubing, and by drilling a hole in the plastic reinforcement of a side of the fan I was able to fit the connection in one of its corners.

Now that the fan is connected to the cable I took the 3D printed piece where the fan will be put. Inside there are two tabs to secure the fan, that have a hexagonal space where I put an M4 nut. Before mounting the fan, I also put two M6x30 mm bolts in the holes on both sides, that also have an hexagonal space to keep the bolt's head flush with the surface. These bolts will be used to attach the fan to the stand while allowing us to adjust the angle of the fan, and they will be locked by the fan once it is mounted. After running the cable through the hole, I inserted the fan into the 3D printed piece, holding the air outlet to the outside. With two M4 screws I secured the fan to the nuts that I had put in the two tabs of the 3D printed piece.

Now that the fan is mounted I glued a 3D printed border on the back of the part that holds the fan, using some super glue, although you can also use hot glue. The border will match the contrast between orange and black that will be created by the filter, that will be put on the other side. Of course, this part only has aesthetic purpose.

On the side from which the fan draws air, we will need to mount the filter that will absorb the fumes created by the soldering iron. First I put four M3 threaded inserts in the 4 holes that are on the front of the part in which we just mounted the fan, heating them with my soldering iron. For this step, it is better to use a soldering iron with temperature adjustment set to around 230°C.

Using the smaller 3D printed grid as a template, I cut a rectangle from the carbon filter. I inserted the filter in the bigger 3D printed grid that has an edge around, and on top I put the other grid. Using two grids with the filter in between prevents the filter from being sucked in by the fan, and keeps it firmly in place.

I mounted the filter in front of the fan using four M3 screws, screwed into the threaded inserts we have taken care of a few moments ago.

Now the block with the fan and the filter is finished, and we can move on to the base and the stand that will hold the fume extractor over our work area. In the base there will be the power switch, an LED and the connector for connecting the power supply.

Also in this part I put four M3 threaded inserts, which we will use to screw the bottom cover on. Then I ran the cable coming from the fan through the hole in the base. In the base I also put a power switch, which we will later use to control the fan.

To join the base to the fan I will use two rectangular aluminum profiles. Specifically, I used a 20x10 mm profile, of which I cut two 20 cm pieces using a manual mitre saw, which allows you to set an angle at which to make the cuts, which then come out quite accurate. After cutting I filed the edges of the aluminum profiles. In both pieces I drilled two 6 mm holes, one 30 mm from one side and the other one 10 mm apart from the other side. To make the holes more precisely I used a cheap drill press, but a cordless drill should work fine too.

I attached the two aluminum pieces to the two sides of the base, with two M6 bolts with round head; the small channel on each side of the base will keep them right-angle, without the need of using two bolts. After securing one aluminum profile to the base I inserted in its hole one of the two bolts that are on the sides of the fan block, putting in between a 3D printed spacer. With another spacer on the other side I then secured the second aluminum profile to the base.

Now that we have mounted it, the fume extractor is free to rotate. So I 3D printed two knobs, into which I pressed an M6 nut using a hammer. I screwed these knobs to the two bolts on which the fume extractor rotates. This way by loosening the knobs we can adjust the angle of the fume extractor as we need, which is something I think is very useful. Instead by tightening the two knobs the fan is locked in the position we have put it in.

At this point we can move on to the electrical connections. First, I stripped the cable that goes from the fan into the base. Next to the switch I also decided to put a status LED, both because on electronic devices there is always an LED and because it looks cool. I chose a blue LED, and soldered a 1 K resistor to the positive leg for limiting the current. To power the LED I soldered a positive wire to the resistor, and a negative wire to the negative leg of the LED. I mounted the LED in a hole I made in the base and fixed it with some hot glue.

Then I soldered the positive of the fan along with the positive of the LED to one of the two pins of the switch. To the other pin of the switch I soldered a piece of wire. For connecting the power supply I will use a barrel connector that fits the one that's on the power supply. After finding positive and negative on the connector with a digital multimeter, I connected the negative of the fan and the negative of the LED to the negative of the connector, and to the positive I soldered the wire coming from the switch. I mounted the connector in the rectangular space on the back of the base with some hot glue.

Now that the electrical connections are finished, I closed the base with its cover, using M3 screws. With these screws I also attached four small feet, again 3D printed, to lift the fume extractor from the table a little bit creating a small shadow, and to prevent the head of the screw from touching directly the workbench.

Now I just needed to connect the power supply to an outlet and turn on the fume extractor. The fume extractor works really well, and it moves a lot of air. I've tried soldering with the fume extractor turned on, and all the fumes were sucked in, even keeping the aspirator at some distance from the soldering iron. Obviously even tough the extractor filters the fumes, at least partially, I still recommend that you always solder in a well-ventilated place, maybe with an open window.

I hope you found this guide interesting and maybe useful. To see more details about this project, watch the video on my YouTube channel. Bye!