Hackerspace Takes Fume Extraction Seriously

At first we laughed at the ridiculously over-the-top fume extraction system this hackerspace built for itself. Then we thought about seriously questionable donation rolls of solder some of the members managed to find and bring in. The kind of roll where the local greybeard assures you that a Californian State Trooper has permission to shoot you if you try to take it into the state, but damn does it solder well. They may be onto something is all we’re saying. But on a serious note, for a communal space like this one, a great air quality plan makes the place a lot more pleasant, if not safer at the same time.

The build uses a regular boost fan for its main suction and pulls the fumes out to a place the members aren’t. Knowing hackerspaces that could be anything from an empty alley to vents on the building’s roof. It’s actually an interesting challenge to solve in a rented space (please share your own solutions for “daylighting” to the outside in the comments).

The frame is made from ducting and dryer hose. Since there aren’t really fittings for this. Most of the joints were designed in OpenSCAD and 3D printed. At each end of the tube a computer fan provides another little boost of airflow. We like the stands to position each end of the hose at the fume source. All of it is powered by a distribution box of their own making with the juice being fed with repurposed Ethernet cables to the fans at the ends of the hose.

It’s a nice build and likely extended the life of a few of the more electronically active members in the space. Especially if the retired radio enthusiasts decide to do their fifty year anniversary garage cleaning and gift upon the space their findings.

22 thoughts on “Hackerspace Takes Fume Extraction Seriously

  1. The flexible vinyl hose is only allowed for venting bathroom fans now. Dryer duct must be aluminum for fire protection reasons.

    There are lots of operations that require ventilation besides soldering. So a workspace that doesn’t have an exhaust system is a major fail. I once saw exhaust ducts on grinders in an oil company research fabrication shop. When I expressed surprise it was pointed out that they didn’t want the grit getting on the machine tools. Many cutting operations generate dust which must be collected and removed. Then there’s welding fumes, solvents and lots more.

    As for solder, anyone not using lead solder because of the health risks is completely daft. Almost every activity in life is more dangerous. At least if you have the sense to *wash* your hands before handling food. I am constantly amused by people who think hand sanitizer is a substitute for washing. I wash the steering wheel and shift lever of my truck after I’ve been using pesticides or herbicides. Even though I was wearing gloves and took them off before driving.

  2. Seconded on making these metal ducts only. Probably also cheaper to buy commercial metal fittings than print them. Burning vinyl is going to be both a bigger acute fire hazard as well as a source of phthalates. These fume extraction hoses really should be metal. Probably aluminum. It can be pretty thin and flexible but get ones rated for flexing. $12 for 10 ft or so. Make sure to ground it, static will quickly be generated by it if there is much of any airflow at all.

    Also, use a decent sized metal blower with this unit. As in at least a HP or so. Can still be 120V.

    Would also be nice to have air vent blast gates that can be closed to concentrate the air to only the stations in use. These are commonly available and fairly cheap, a few bucks each for common 4″ duct sizes.

    Lead fumes are not good for you or anybody else in the work space and are an additive health risk. Better policy is to implement this as well as a lead free solder policy.

    1. Regarding the “metal ducts only”:
      Flexible PVC melts at 325 F. Do you have any proof that the fumes from soldering are coming out hotter than that? I don’t mean to be condescending, I just think before we dismiss this hacker space’s fume extraction system, we should actually know some facts. Lets not confuse the tip temperature with the fume temperature.

      But I’m glad to see a hackerspace taking these things seriously. Lead oxide fumes, flux fumes, 3d printer fumes, solvents, wood dust, etc are all hazards. It’s one thing to be exposed to them occasionally, but if the hackerspace has staff or regular members then these things should be treated as occupational hazards.

      I use a tip extraction system on my soldering iron. The $800 was hard to spend, but I’ve had it for 5 years now and do not regret it.

      1. Static charge issues. The reason the vinyl duct was discontinued for use with dryers is due to dryer lint and static charge buildup in the tubing. Put those two together and you have a house burning down. Obviously not much flammable about solder fumes but static discharge can be an issue around the electronics that are being used and worked on. Make do solution would be to run a conductive wire grounded at both ends through the vinyl tubing.

      2. I’ll remain to be see how well the ducting holds up, but in the short-term we’re seeing no degradation of the vinyl at all that we can see. The airflow isn’t huge, it’s just enough that it pulls the fumes away from soldering really effectively and exhausts them out the window.

      3. Solder tips achieve well past 325 F in use and are very likely to accidentally come in contact with the hoses in a multiple station, publicly open maker space environment at some point in time. The fume temperature is likely to be lower than the melting temperature but the concern isn’t the fume temperature here. It’s the flammability and meltability of something being used in close proximity to a soldering iron tip. Use a nonflammable, metal hose. They are not expensive. Every time somebody argues that PVC pipe is safe for air pressure because it is slightly cheaper, the same arguments are made. Use the right material for the application.

    2. Lead-free solder fumes are much worse than leaded due to the more aggressive fluxes. Flux is the only component of fumes at normal electronic soldering temperatures.

  3. Adopting a lead-free solder policy is the way to go. I made the switch a few years ago across the board and haven’t found a situation where it limited me in any way. I build circuit boards that are regularly handled by children as a standard use case and childhood lead exposure is nothing to mess with. It’s long past time we moved beyond toxic metals whenever possible as a community, especially when the only real argument is convenience and resistance to change. I don’t buy tin whiskers actually effecting 99.99% of projects, but feel free to enlighten me if you have personal expierience with such a failure.

    1. I think the fume extraction is mainly needed for flux fumes and not because the solder has lead in it. Some RoHS solder alloys need more aggressive fluxes so might be even more important to have fume extraction.

      1. You are right that it is the FLUX fumes which are being extracted. Lead vaporizes at 3180 degrees, much much hotter than soldering temperatures. The hazards associated with lead based solder involve holding the solder in your mouth while working so as to free both hands, or failing to wash up after handling solder before handling food. In other words, ingesting solder is dangerous, but the fumes from soldering aren’t lead vapor, and while rosin flux fumes can be irritating, they aren’t a lead poisoning hazard.

      1. Word.

        I have a roll of lead free solder, that I use for products that require RoHS compliance. All personal projects and work are done with good old 63/37 though. I have a shelf of “old solder” that I’ll continue using till it’s gone. If I get any indication leaded solder is gonna be phased out… I’ll try to do enough of a final buy to last me till the day I die!

        All the money spent, and unreliability introduced… Over what? Hyped up environmentalist fears, that aren’t even based in reality… Ugh… /)_-

        Thanks for linking those.

  4. I know 8 points probably seems OTT, but the soldering workshops we occasionally put on are somewhat popular, and when you have 8 people who are learning to solder at the same time, it’s nice when you can make sure they all have local fume extraction

  5. Also, a lot of “lead free” formulations stress delicate components such as LEDs, in fact its better with these to use lead solder simply to reduce the chances of a failure. I’ve found that with the typical 0603’s lead based solder paste has about 100% success rate whereas the lead free (SnAgCu formula has about 75-80%. On the same diodes!!

  6. Nice space! Obviously nothing gets past a cold trap if it is cold enough, but the old “bin o charcoal” will trap most things too. Put it through a cyclone then HEPA filters to eliminate particles first.

  7. Do the small fans at the working end of the hose actually do anything, except blocking some of the airflow? If you have that large boost fan at the end of the hose-system pulling air, the small fans can’t just “accelerate” that air more. Maybe it looks that way, since the little fans make the working end a bit tighter (venturi effect) but they don’t really have the power (static pressure) to increase the air flow volume of the system. I’d say it would be better to ditch these little fans and make a better nozzle for the workplaces, maybe even one where you can adjust the flow or close unused intakes. Since you have 3D printers, it should not be that hard to make something yourself.

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