For most of the history of industrial electronics, solder has been pretty boring. Mix some lead with a little tin, figure out how to wrap it around a thread of rosin, and that’s pretty much it. Sure, flux formulations changed a bit, the ratio of lead to tin was tweaked for certain applications, and sometimes manufacturers would add something exotic like a little silver. But solder was pretty mundane stuff.
Then in 2003, the dull gray world of solder got turned on its head when the European Union adopted a directive called Restriction of Hazardous Substances, or RoHS. We’ve all seen the little RoHS logos on electronics gear, and while the directive covers ten substances including mercury, cadmium, and hexavalent chromium, it has been most commonly associated with lead solder. RoHS, intended in part to reduce the toxicity of an electronic waste stream that amounts to something like 50 million tons a year worldwide, marked the end of the 60:40 alloy’s reign as the king of electrical connections, at least for any products intended for the European market, when it went into effect in 2006.
You’ll often hear about some study in the media and then — on examination — find it doesn’t really apply to your situation. Sure, substance X causes cancer in rats, but they ate 8 pounds of it a day for a decade. That’s why we were glad to see [Chuck] post a series of videos about 3D printing air quality based on his practical experience. You can see the summary video, below.
[Chuck] is quick to point out that he isn’t a doctor or even a chemist. He also admits the $100 meter from IGERESS he is using isn’t necessarily high-quality test gear. Still, the data is a good guideline and he did get repeatable results.
If you are a maker, chances are that you will be exposed to unhealthy fumes at some point during your ventures. Whether they involve soldering, treating wood, laser cutting, or 3D printing, it is in your best interest to do so in a well ventilated environment. What seems like sound advice in theory though is unfortunately not always a given in practice — in many cases, the workspace simply lacks the possibility, especially for hobbyists tinkering in their homes. In other cases, the air circulation is adequate, but the extraction itself could be more efficient by drawing out the fumes right where they occur. The latter was the case for [Zander] when he decided to build his own flexible hose fume extractor that he intends to use for anything from soldering to chemistry experiments.
Built around not much more than an AC fan, flex duct, and activated carbon, [Zander] designed and 3D printed all other required parts that turns it into an extractor. Equipped with a pre-filter to hold back all bigger particles before they hit the fan, the air flow is guided either through the active carbon filter, or attached to another flex duct for further venting. You can see more details of his build and how it works in the video after the break.
Fearless makers are conquering ever more fields of engineering and science, finding out that curiosity and common sense is all it takes to tackle any DIY project. Great things can be accomplished, and nothing is rocket science. Except for rocket science of course, and we’re not afraid of that either. Soldering, welding, 3D printing, and the fine art of laminating composites are skills that cannot be unlearned once mastered. Unfortunately, neither can the long-term damage caused by fumes, toxic gasses and heavy metals. Take a moment, read the material safety datasheets, and incorporate the following, simple practices and gears into your projects.
When you’re soldering, smoke rises from your iron. That smoke is full of a variety of chemicals, depending on what type of solder you’re using, but it’s almost certainly not good for you. That’s why you can buy fume extractors to suck smoke away.
But benchtop extractors tend to suck, and not in the way they’re supposed to. It can be hard to get the extractor to pick up all the fumes, leaving fumes that float into your face.
Over at Other Machine Co., they built up a custom downdraft fume extractor to solve this problem. The downdraft extractor is a table that you work on, providing downwards suction that grabs the fumes. Their table uses a standard MERV13 air filter that’s rated to trap particles as small as 1.0–0.3 μm. Cooling fans provide the airflow, and a piece of perforated sheet metal acts as a work surface.
The table works great for soldering, and is also helpful for working with other chemicals like adhesives and solvents. DXF files for the frame parts are provided, and everything else can be sourced from McMaster.
A good soldering station and fume extractor is a must for anyone interested in hacking and modding, but not everyone can afford the expensiveprofessionalmodels on the market. This How-To and the tips within it will guide you through the process of building an inexpensive homebrew fume hood complete with built-in time and temperature controlled soldering station and all the soldering tools you need.