Introduction: DIY Fume Extractors

Welcome to this instructable. Today we will build some fume extractors.

As a person that solders a lot, the fumes dissipating from the molten solder can be very dangerous. So i thought let´s build some fume extractors.

As shown in the pictures, i will show you how to build a set of three Fume extractor boxes. Two 120mm fans and one 80mm fan. The two 120mm fan boxes will be connected by a hinge and can be shut together. The 80mm fan will be connected via an extra power line from one of the 120mm boxes. So if you don't need it you can store it away.

Building the all the boxes took me around 7h spread over two days. It cost me around 70€ and yes i know there are less expensive models out thereto buy, but they often look awful and are loud as hell and are not DIY.

Step 1: Gathering All the Parts and Tools

Because the build is fairly simple you don't need any extra knowledge in electronics or gluing.

First, all the tools i used:

  • a carper cutter
  • hot glue gun and hot glue
  • normal glue ( i used UHU HART : )
  • soldering iron and solder
  • pencil and ruler
  • metal saw
  • wire cutter
  • wire stripping pliers
  • pliers

Now the materials :

  • wires i had lying around
  • 2x switches
  • 1x 12V Power supply
  • 1x low-voltage connector socket 5.5mm / 2.5mm Cliff ( )
  • 1x low-voltage connector socket 3mm plus cable with fitting connector (you can use any other connector typ if you want to, it must support 12V DC)
  • some kind of air filter (i used one that would be used in a air purifier)
  • metal mesh to support the air filter
  • 1x 80mm PC fan 12V DC ( )
  • 2x 120mm PC fan 12V DC (
  • piano hinges ( )
  • machine-wood-cardboard (aka "Finnpappe", here is a link to german website, normal cardboard does the trick as well)

Step 2: Planning

The plans are fairly simple. You can use mine for your project or use them as inspiration for your own design.

Step 3: Cutting Everything

First of all, i drew all the shapes onto the cardboard, making sure not to waste any material. Than i cut out the basic shapes.

On some of the shapes i glued the plans from my pdf and startet cutting the circles and other things like the holes for the power socket or the switches. Where and how often you have to cut things, can be found in the plans.

After cutting everything i dry fitted them, what was really hard to do, but if you cut careful and always stay on the line, everything will fit.

On tip for cutting the circles: for smaller holes you can use a hole punch. For the bigger circles, i find best to divide them like a cake and than start cutting the outer rim. But if you find another and maybe easier way of cutting the bigger circles let me know.

Step 4: Painting the Parts

Well the title of the step says it. I painted everything with normal black spray paint. Don't use to much because it can warp the cardboard or bring everything in misalignment.

A handy trick is, when you painted a piece, let it hang from something, so that i hangs freely in the air. That speeds up the drying process and you can paint all the pieces in one go.

Step 5: Building the Back Plates

This is also fairly simple, you take the metal mesh and cut it to size. Please take notice, that the rim of the walls need to fit on the back plates, so leave room for them, as shown in the picture. If have cut them to size, glue them on with a good amount of hot glue, so that they stay in place.

As i already mentioned, use a hole puncher to punch smaller holes in the box sides. If you do not have a hold puncher you can just cut the holes with a exacto-knife. If those should look ugly just spray paint them and they don't look that bad anymore.

Step 6: Building the Small Box

First of all, you need to glue in the fan. To do this, just make sure, that it will blow air out at the back. Than use hot glue on every corner of the fan and press it firmly on the metal mesh until the glue has hardened.

Than you can glue in every single wall. One wall is shorter or not that wide as the others, that is to compensate for the 0,4mm thickness of the cardboard. And it is very important to make sure that the wall with the switch in it, is at the top of the box. Therefore, the wall with the cable comping out of it must be perpendicular to the wall with the switch.

I used hot glue for that and went a little bit crazy and put a large amount of it every where. It will be enough if you use normal Glue for the walls and to stabilize them put hot glue on the inside, as shown in the picture.

Step 7: Wiring and Finishing the Small Box

The wiring is fairly simple: First of all you have to connect the switch to the fan. Because my switches only had one input terminal i only connected the positiv wire of the fan (in my case it was the yellow fan wire).

Than you connect the other pin of the switch with the positiv wire of the cable with the plug at the end.The negative wire of the fan, can be directly connect it to the negativ wire of the cable.

Thus concludes the wiring. Now you can glue in the switch and rout the cable out of the box through the hole.

Now you can finish the box assembly. First of all you have to glue in the second metal mesh, which will hold the filter later. Make sure you leave enough room for the filter, so that you can stuff the filter later. Over that you will glue the front plate, as shown in the picture.

The filter now can be cut to size and stuffed into the space between the front plate and the metal mesh.

Now you have finished the small box. If everything worked out so far the assembly of the bigger boxes will be easy.

Step 8: Building the Bigger Boxes

The building of the boxes is the same as building the small box. Only that you to repeat it twice.

One box will have the switch and the connector socket for the main power. Here applies the same as for the small box. The wall with the connector socket must be perpendicular to the wall with the switch. So the switch will be at the top and the connector socket at the side. The side with the hole for the cables in it must be parallel to the wall were the connector socket is.

Both boxes will be connected, so the alignment of the boxes is important. When you look from the back (at the metal mesh circles) at the fume extractor, the holes, were we will rout the cables through will be on the left side of the box with the switch on it. And on the other box it will be in the right wall.

The other box will have the connector socket (3mm) for the cable from the smaller box. The side with the hole for the cables in it must be parallel to the wall were the connector socket (3mm) is. When gluing in the connector socket, make sure that the plug can reach the connector socket and make contact.

Step 9: Wiring and Connecting the Bigger Boxes

Lets start with the less complicated box, the box with the 3mm connector socket for the plug of the small box.

You only have to connect some cables to the negativ and the positiv pins of the connector socket, and then put them through the hole on the side and stick them through the other hole into the other box. The same process applies to the cables of the fan in the bigger box. Make sure you leave enough cable length so that the boxes can swing freely (as shown in the picture).

Before wiring the rest in, you have to connect the boxes via a hinge, therefore cut the hinge to size and glue the hinge on both sides, making sure the cable holes and the switch are at the right position (as shown in the picture).

Now you can move on to the last box. First of all you can wire in the switch, therefore you have to connect the positive cable of both big fans to the pin of the switch. The second pin of the switch will be connected directly to the positiv pin of the connector socket. All the negative wires will be also directly connected to the negativ pin of the connector socket.

Now there should only be one last cable. The positiv cable from the connector socket of the smaller box. This will also be directly connected to the positive pin of the connector socket.

For the rest of the boxes you have to do the same thing as with the small box. Glue in the metal mesh and than the front plate.

Step 10: Finished

And now your own and cool fume extractors are finished. I hope you liked it and that you also had fun building it.