In this thread I will document my build of a poor man's fume hood. It may not look like it yet, but this cardboard box will become a functional fume hood in few days.
Cut out a large window into the box through which you will perform tasks inside the finished fume hood. It does not need to reach all the way to the bottom.
Cut out a hole for the exhaust in the opposite side, situated closer to the top so that rising fumes can be extracted.
Cut transparent plastic foil (it needs to have some thickness, cling film is insufficient) to fully cover the working window from side to side, but leaves the bottom 10-15 cm uncovered, and use adhesive tape to fix it to the fume hood on three sides (not the bottom).
The exhaust needs some more work and will be shown in the final post.
Meanwhile I've also built this contraption as a side quest before I finish the primary exhaust. The paper tube was cut crosswise about 12 cm deep from one end. The resulting segments were bent to fit a 12V computer fan and the pipe has essentially become a converter from round to square cross section. The fan was hot-glued into place and the gaps were sealed with adhesive tape. It is fugly as hell but it kind of works, however the fan is too weak and does not provide the expected air flow. I am unlikely to use it for the fume hood but it will do its job to extract fumes when doing soldering work on some electronics, for instance.
I'm thinking you are not going to make your recommended 100ft/minute air speedyou would, of course, need 100 cfm to achieve 100 fpm in a 1'x1' opening. Just thought I would toss that out there when you are window shopping and day dreaming about fume hoods, that's what you are trying to shoot for. Less and an energetic reaction will exceed the capabilities of the hood. That's just what was beamed into my head. Don't take my word for it🫨
Told you that the cheapest solution is 50 euro (yeah now its 60 or so) 500 m3h 150mm fi PP made vent.
it has another plus. so its 2 birds one stone,, you can multiply them like 2-3 pieces so you have exhaust in many places then you can connect them into 3 pipes splitter (dont know the name) and it can be sucked by pressure vent that puts this air into filter (no loses from any vent)
I'll get to that point later. Until then I'll finish this improvised build using things I already have and learn from experience what I really need to get and improve.
This. This is the exact opposite of a fume hood. This is a laminar flow cabinet . It blows air OUT of that 24x24x11.5 Neuclear certified HEPA filter. Under the top housing is...a squirrel cage blower out of a furnace. A fume hood protects you from the chemicals, but this protects the stuff from you mushrooms, but plants are often cloned in front of one and pharmacists and microbiologist use them . The 99.997% percent efficiency of the filter blows air at way faster than laminar speeds, to displace atmospheric air that could be contaminated with mold or bacterial spores. This thing served me well for 10 years practically 100% success. After 10 years, I sold it for the $200 I built it for. Laminar is just a catchy phrase, laminar flow in atmospheric air is a fairytale. , not to mention laminar flow is not a thing, it's a measurement and the unit of measurement is called the Reynolds number.
I think a better option instead of using a cardboard box and some hot glue, would be a a small grow box with an akf + extremely oversized ventilation. And I suggest to blow out the air of the outlet out of the window.
If you working in the tent, of course you'll need normal protection gear (A2B2E2K2-HG-P3 filter mask !!).
But instead of buying a real fume hood, this would be the option I'd use.