Introduction: DIY Fume Extractor

I've spent too much time breathing the stuff that emanates from the tips of soldering irons. After checking out the available fume extractors, I thought I could do better putting something together myself. If it didn't turn out that way, at least it would be my loud, expensive, and low air flow fume extractor. Maker’s remorse is always better than buyer’s remorse.

Luck was on my side this time and I don’t have to deal with any remorse. I’m happy with how this project turned out. There’s more than a couple improvements that I could make and more than a few things I could have added at the beginning, but keeping it simple helped get it done. This DIY fume extractor does the job and it's a great addition to my work bench.

WARNING: This project requires making AC power connections. Please give it the diligence it deserves. Don't take risks that might end up hurting you or someone else.

Step 1: BOM

Bill of Materials:

Cooltron AC Axial Fan 120mmx120mmx38mm 110 CFM 2600 RPM
Carbon Filter Material
2 x Silverstone Fan Filter with Grill 120mm
120mm Chrome Fan Grill
Hammond 1415D 6”x6”x6” Steel Enclosure
16A 125V DPST Rocker Switch E-Switch RR812C1121 or equivalent

1/4” Wire Grommet
Wire Eyelet
4 x 2” #8-32 Machine Screws
4 x 1.5” #8-32 Machine Screws
4 x #8-32 Nuts
4 x #8-32 Nylon Lock Nuts
4 x #8-32 Wing Nuts
IEC Power Cord (Computer Power Cord)
Shrink Tube
Rust-Oleum “Hammered” Black Spray Paint 7215830
Self-Adhesive Rubber Feet

Step 2: Cutting and Drilling

Find the center of each lid and layout the locations for the fan and grill mounting holes

Cut a 4.5” hole in the center of each lid, and drill the grill and fan holes

Layout the holes for the power switch and power cord on the enclosure. Leave enough space to clear the 1.5” thick fan. I drilled my switch hole too far back and it was a bit of a pain to modify the fan, etc. to get it all to fit.

Drill holes for the power switch and cord. I used a .75" – .5" shank drill bit which is a little small for the switch. I opened up the hole and cut the keyway by filing out the extra material.

I had some thumb screws laying around that I thought would make the fume extractor look more awesome and make changing the filter easier. I drilled out the original lid holes in the enclosure and tapped them for the thumb screws.

Step 3: Mock Up the Fume Extractor

Mount the fan and chrome grill on the back lid with the 2” #8-32 screws and nylon lock nuts.

Use one of the Silverstone grills as a template to cut a square of filter material and poke the mounting holes

Mount a Silverstone grill on the other enclosure lid using the 1.5" #8-32 screws and nuts

Slide the filter down the 1.5" #8-32 screws and place the second Silverstone grill on top

Secure the Silverstone grill with 4, #8-32 wing nuts

Mount the filter sandwich and the fan in the enclosure with the lid screws included with the enclosure.

Make sure everything fits. If your switch hole is just big enough, it can be difficult to pop the switch in and out. I made sure the switch fit when I filed the hole. Rather than struggle with the switch, I ran the power cord that came with the fan out the switch hole so I could power the thing up. If everything fits and works up to this point, disassemble everything and get ready for paint. Depending on how your enclosure fits together, at this point you might want to make some notes on the back of the lids and inside of the enclosure denoting top, bottom, front lid, back lid, etc.

Step 4: Paint

Scuff the entire outside surface of the enclosure and lids with Scotch-Bright to help the paint adhere to the surface.

Clean and remove all dust, oil, and dirt from the surface to be painted.

Paint the parts in a well-ventilated, well lighted, area. I hung mine in the garage with modified wire clothes hangers after blowing the dust out the door, and off the parts, with a compressor

Follow the directions on the can and allow the paint to fully dry

I’m amazed at how the Rust-Oleum “Hammered” finish turned out. I’m in love with this stuff.

Step 5: Final Assembly

Determine which fan mounting bolt is going to hold the ground wire and remove the paint from the fan in that area

Mount the fan and the chrome grill on the back lid leaving the nylon lock nut intend for the ground connection loose

Insert the .25" wire grommet into the power wire hole on the enclosure

Cut the C13 (computer plug) off of the IEC power cord

Pass the cord through the wire grommet from the outside of the enclosure and pull through a good length of cord

Strip the outer insulation off of a sufficient length of the power cord to expose the insulated conductor wires

Tie a knot in the power cord to prevent it from being pulled out the power cord hole and grommet. This stain relief will protect your connections should the cord get pulled or yanked.

Strip all three of the power cord conductors

Cut the fan connector off the power cord that came with the fan with a little more than enough wire to reach the switch

Separate and strip the fan cord’s conductors

Pass all four wires out the power switch hole, add shrink tubing to all four wires, and solder in the switch (consult the switch data sheet and/or pin out the switch with a multimeter to ensure a proper connection)

Strip the ground wire and install the eyelet

Install the lid/fan assembly, switch, and ground wire

Plug the power cord into an outlet and test the fan and switch

Unplug the power cord

Assemble the filter sandwich and install the front lid

Stick the self-adhesive rubber feet to the bottom of the enclosure

Step 6: Voilà

That's it. Now you can breathe easy while soldering.

Thanks for reading.