Fume Extractor

From The Mind of Gabriel Shear

Thursday, June 26 2014


Fume Extractor

Disclaimer: Information presented here is for educational purposes only. The author and website are not liable for any damages caused by the misuse of this information by others.

This is a design for a fume extractor for removing the fumes while soldering electronics and other parts. It is simple, and yet effective at its job while being cheap and easy to construct. If you’ve ever done any soldering, you know that the fumes can be very noxious. Rosin flux smells fucking awful and isn’t to healthy to breath.

Below are the parts you will need:

Qty.               Part Description

1                   4x4x2 Plastic Electrical Junction Box

1                   12vdc Electric Fan (scavenged from old PC)

1                   12vdc Power Supply

1                   Power Switch

1                   Power Connector (optional)

2ft.                18 AWG Wire

1                    Pack of Carbon Air Filters ( one pack should last a lifetime!)

1                    4 Inch Strip of Self Adhesive Velcro


After you have gathered all the parts you will need, you can begin construction. The box was purchased for 6$ at a local hardware store along with the pack of carbon air filters for 9$. The rest was scavenged from old electronics.

All Parts

Start by cutting a hole in the back of the box as close to the size of the electric fan as possible. A 2 1/2 in. hole-saw was used on this one. Holes were also drilled to match the mounting holes of the fan.

Back hole

After mocking up all the parts to make sure everything would fit. It was found that the fan would have to be off-center to fit the other parts inside. A hole was drilled in the bottom right corner and a small file was used to square it up to fit the power connector which was then  glued in place. The Fan was then screwed to the box and the power switch installed on the top.

power connectorpower switch

After everything was mounted in the box polarity of the power connector was checked by plugging the power supply into it and checking with a voltmeter which pin was positive and which was negative. Everything was then wired together. The negative terminal on the power connector gets wired directly to the negative power leg of the fan. While the positive leg goes to one leg of the switch and from the other leg of the switch to the positive leg of the fan. This way the switch is breaking the power to the fan on the positive power leg.

power diagram

Once everything is connected, power it up to ensure that everything is functioning correctly and that the power switch is operational. A power cube from and old network switch was used. It was rated 12 vdc @ 1 amp of available current draw. The fan only uses .25 amps so this was plenty.

Next taking the front cover, a series of holes were drilled in to it. Four larger holes and one smaller center hole was found to fit nicely.  Four pieces of the Velcro were attached to the backside of the cover using the hook side of the Velcro and not the loop side. Next a piece of the carbon filter was cut to fit shape of the lid and stuck to the Velcro to hold it in place. Finally the plastic wings on the box were removed and the front cover was screwed back to the box and everything was tested once again.

front coverCarbon Filter

You now have a fume extractor to remove fumes while soldering. A useful tool to have.

finished unit


The power connector is optional, the power cable could be ran through a small hole and wired directly to the circuit. Tying a knot on both sides of the cable where it goes through the box would prevent it from pulling out or getting pushed to far in to the box, possibly getting caught in the fan.

-Gabriel Shear