Homemade Soldering Fume Extractor Station

The purpose of this instructable is to build a fume extractor that you could solder in. This station allows you to solder in it safely while keeping toxic fumes out of your face. This is only meant to protect you, but you should still be soldering in a well ventilated area and be sure to take the safety precautions that you would soldering. Do not use this inside unless you are using a hepa filter.
And this is my first instructable so I hope you enjoy! Feel free to comment and i would like to hear from you if you built one.

Step 1 Materials

You will need...
A cardboard box that you can has plenty of space so that you have enough room for soldering
A layer of sheet metal that will be your platform and it will keep the table safe
A 120v fan that is bigger than 6 inches in diameter or a 12v fan of similar size
A small area of space on a table that wont burn
And the basic soldering tools
Screws with washers and nuts of the same diameter
A knife capable of cutting cardboard easily
A power strip with an on/off switch and at least 3 outlets
(optional) Some alligator clips and solid copper wire
(optional) An air filter that could collect the fumes
(optional) A lightbulb and power source for it

Comments

[mcarrell]

Great concept. We used fume hoods like this at work all the time to remove Acetone fumes when cleaning laser optics. We never smelled the chemicals we worked with thanks to these heros. Our units however were of course more expensive because they were certified for use in class 10 100 clean rooms.. But there is no need to pay such outrageous fortunes when you can make some improvements to a design like yours in short order which would on a practical level rival many of the best clean-room class fume hoods in terms of providing effective protection of the person using chemicals or soldering in the hood..

One really needs filtration of the exhaust air because it is heavily contaminated with vaporized metal and VOCs which come from the vaporizing of the tin in the solder, some from the flux, and some from the various known and unknown compounds of vaporized "dross" and unidentified unknown contaminants stripped by the flux and those that ultimately work their way into the flux paste (or liquid) and solder as they sit or oxidize during cooling and heating or just sitting on the shelf (dust)....

The fume hood system is "open-loop" here, so it will try to act like a closed loop by drawing the already moving air coming from out the back (which has less inertia to overcome than the still air from the rest of the room) through a turbulent vortex of circulation back to the front of the unit to then be sucked in again in what becomes one big circular loop. This means the air comes straight towards the user's face over the top of the hood before being sucked back down into the hood's front. That's not good.

Protect yourself (eyes, ears, nose, mouth, teeth, throat, and lungs) from these nasty carcinogens and install carbon/HEPA filtration in the very least. Better yet, do that AND add an exit hose to force the exhaust outside so that when the filtration fails (or if it isn't 100% in the first place), the remaining carcinogens are still removed from your working space indoors and instead sent outside to be diluted with outside air. A standard, cheap drier ventilation kit is all you need to connect this to to make the effective protection of the fume hood 100-1000 times better at keeping poisonous fumes from collecting in your indoor environment..

You may also want to move the fan up so that it is abutting to the top of the unit or in fact in the top of the unit because the contaminated air is less likely to be drawn into the fan than the surrounding cooler air because the energizing of the air by heating of the soldering iron causes the contaminated, smokey air to rapidly move upward (convection) to climb over the cooler, denser air which gravity wants to keep below it. This means some of these fumes will hit the top of the hood and flatten out, dispersing evenly in all directions, with some of it possibly escaping out the front of the unit and up into the breath intake of the person soldering and into their eyes. This effect is more pronounced if soldering closer to the front of the hood of course.

An easy, practical way to help prevent all or most of that would be to install a section of clear plexiglass covering the top half of the open front so that hot smokey gases can pool and collect at the top and cool then fall into the path of your fan's intake, sucking it out eventually. The additional plexiglass trap also helps to raise the pressure of incoming air and force air to be drawn in from only the bottom half of the front at significantly higher pressure which aids to make sure contaminates have much less change of escaping because this should nearly double the pressure of air coming in ensuring that the inbound airflow is more consistent in pressure across the board and making it harder or impossible for fumes to escape out the in.

You may also find it helpful to install bright, high-efficiency L.E.D. task lighting just under the inside lip of the top of the unit to aid in accurate soldering and cold-solder inspection of tiny items as the hood itself may block a bit of the ambient light in the room from reaching what you work on below it. Task lighting is always better for soldering than room-lighing anyways... It's another thing that will help save your vision and decrease accidents, flaws and mistakes while soldering.

Yeah, sorry, I wrote a book, but I figured this detailed information might help some others out their still undecided how to design fume hoods as to what things they should consider to improve their design.

[Crapxxas19]

I finally read your whole comment and you helped me learn that I didnt write the purpose clearly. My sole purpose of this project is to get those fumes out of your face. I still solder in my garage with the doors open. However, your comment about the placement of the fan was very helpful. I will probably work on a more permanent design with the fan being placed higher, but the concept of the overall airflow moving is justified that placing my fan anywhere on the back side was good enough. I didnt realize that there was probably an air pocket above the fan.

And like most instructables, this is to give you ideas. There is no instructable that you must follow by step by step without a personal touch to it. I will definitely change a bit of my instructable to include many of your ideas.

I would really like to work with you a little to master the design.

[mcarrell]

Well I told you the essential basics, but there is one more thing that occurs to me, and that is there will be a rate of air intake at which point nomatter where a stream of fumes is rising from in the hood, the overall pull of air molecules in will not let any of the smoke escape in the upwardly direction. If you had one side of it done in plexiglass so you could see from the side a stream of thick smoke from something like rubber insulator or something else particularly visually obvious erupting from the end of the iron, you can move the iron around in the environment up and down and closer and further from the entrance of the hood while you vary the voltage delivered to your exhaust fan using a variac in order to figure out what the minimum flow is necessary to ensure full capture up to the edge of the hood. Once you know that, you can adjust your flow rate up say 10% for safety margins (accounting for possible downward drift over time in fan RPMs and flow from decreasing efficiency as bearings get old/slowdown or for fans that aren't strictly self-regulated).

Air flow (measured in Cubic Feet/Min--CFM or Liters/Min-LPM) can be measured from the input side or the output side without filters in place to test your throughput on the system. Probably easiest to measure on your output side and occassionally should be rechecked to make sure it maintains this rate and doesn't drift downward past the point which may fail to capture and remove all fumes. A good flowmeter gauge isn't hard to make. I'm sure there is probably an instructable on that.

For systems that are highly filtered but ultimately return air into the general room, the lowest-drag setups in terms of the least resistance to increased airflow have the fan and filters positioned directly over the center or rear of the top of the unit to take advantage of closer proximity to the front air intake rather than from the very back-side of the unit. As the closer the fan is to the front, the lesser the air travel distance required to make a loop from air-out to air-in thus the greater the flow and lower the pressure.. This also allows the unit by not having exhaust coming straight out the entire back of the fume hood to now be placed directly against a wall for convenience of efficient use of space. If a fan sucks air up through the top, then it puts it right in line with the easiest no-tripping over it method of ventilating the exhaust by putting it up through the ceiling and then going sideways to the exterior wall or continuing up and out through a roof vent.

If activated carbon filtration and HEPA filters are too rich, but you have lots of extra fan power to spare, There is a poor mans filter you can create if the fumes can't be ventilated to the outside for any reason by running the output air down into the bottom of a water chamber and letting it bubble upwards out of the water at the top. This will cool the air released to reduce smoke and capture some of the heavy metals out of the air into the water. Occasionally, that water will have to be changed because it absorbs a lot of the toxics released from soldering. Without significant push though, this kind of filter may be difficult to enact because of the heavy back-pressure the water will cause which will greatly retard your air-flow, so the better filtration is still a single or double stage filter starting with a HEPA filter for particles that endanger breathing and lung tissue, then ending with a carbon filter to reduce odors. If you really want to get the air clean, add to the mix an ionizer. There is an instructable I just noticed somewhere for building your very own negative air ionizer:

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Ionizers will remove just about any size particle of pollution from the air. And I highly recommend that to scrub your environment free of the pollutants emitted by things that burn on the tip of your soldering iron. I can't help but think solder inhalation is one of the reasons why one of my former coworkers died abruptly in the space of one and a half weeks of a rapid throat cancer. She didn't even know she had it until it was near the end (somehow).. :( That made me quite a bit more cautious about standing over the wave-soldering machine from then on and keeping solder fumes as far from me as possible. I've also been really keen to take lots of anti-oxidants because in my former work environment we were unable to get adequate ventilation or filtration installed by the management. Yeah, they really cared about the workers... Heck, we used to have to run around with buckets during rain-storms just because it took those cheapwads 10 years just to get a roof replaced!

Anyways, my last thoughts on the subject unless you would have further questions of me would be to just make sure your hood is quite well sealed except of course for the one entrance where your hands enter with items to be worked upon and for the exit hole where the fan sits and make sure that it's vented out of the building with clothes-dryer style ducting and/or filtered with high-efficiency HEPA filtering, carbon filtering and/or negative ionization as can be afforded or as materials are available to do such. HEPA filters are a pain because they have to be changed out every few months to ensure they do not clog and leak.. Ionizers are very low maintenance however and rarely need any kind of cleaning depending on their implementation. Carbon filters can be washed, but not too many times as they are delicate and they tend to fall apart and its usually recommended against washing them because of their delicate makeup.

Glad I can be of any help to you on this.

-Matt

[Crapxxas19]

Well for my personal purposes, filtering is the least of my concerns. I am definitely going to work on getting the fumes out of my face because that was the purpose of my project. My filter will come a bit later, but right now im gonna make it out of some plastic material and I will be sure to seal it and everything. Then i will probably mount a hepa filter in the back (99.97% is the best i have) and i will enjoy!

And you probably should have known this before but im am in my mid teens which explains everything about my project.

[MaXoR]

I like the enclosed box design. reminds me of those tornado generators we used to build in school.

[Crapxxas19]

My purpose of enclosing it into a box is that all of the soldering essentials are in this one box.
Also, the box serves as a shroud so that the overall air flow comes from the inside of the box so no soldering fumes escape.

[dragontirex]

oups so my ideea wasn't so great , i'm going to make one of these tomorrow ,thanks alot :D

[Crapxxas19]

The difference between mine and most others is that mine is mor of a soldering station.
What was your idea???

[dragontirex]

well mine was an 3rd hand with an fan below it and an metal plate behind it :P

[Crapxxas19]

Well, im glad that you liked my design.