Modern solder flux are scary. Period. Once, I ordered a professional flux and a quick read through the ‘consequences’ of it’s usage looked like a damn curse to me: Cancer, birth defects etc. You don’t have to be Ph.D. in biology to get that this flux must be a hell of a mutagen, so I decided to put it somewhere far away. Anyway, rosin was and is my flux of choice. It’s much safer, but still not ideal. You do have to filter the smoke anyways from their selection, unless you are fond of headaches. So, this project was just asking to be done:
To make such a scary thing you’ll need:
- A good AC fan. A go a couple of nice 220v fans from china.
- A dust filter. Local hardware store has them, Chinese wholesale shops have them. Guess where’s cheaper.
- Carbon filters. China again.
- М4 bolts (12 pcs, good old Soviet stock)
- М4 nuts (4 pcs, good old Soviet stock)
- Screw tap, М4 (yet again some good old Soviet stock)
- 3d-printer (or a friend with a 3d-printer) to print a few parts.
I started out by measuring the parts and making this scary shit in OpenSCAD:
And added a cap, so that the carbon filter won’t fall out..
The structure of the whole thing is as follows (Just in the same order the air flows through it)
- Dust filter. Dust will settle down here, you’ll need to clean it really often
- The fan itself
- Carbon filter in the plastic 3d-printed enclosure
- The cap, that holds the filter there
- Yet another dust filter
I added the second dust filter at the very last moment. There are small pieces of carbon filter left inside that tend to fly out when you turn on the fan. The last dust filter just keeps them there for you.
The assembled thingie looks somewhat like this: 
That’s it. You can use a relay to switch this on and off, but that’s another story 😉