How to seal a plastic container? And will a passive intake let smell out?

The thread title actually should say "How do I calculate passive air intake size?"


I will be using a container just like this one to make a stealth drying box. View attachment 2415837
for the air intake, I will be making a passive air intake, but I have heard people recommend anything from 1-3 times the size of the exhaust hole as the intake to achieve proper neg pressure, and I was wondering, does the CFM of the fan determine the size of the cut outs more than the physical size? I need this box to have no smell leaking and
I don't want to bottleneck the fan by creating LOTS of neg pressure, but on the same token, I can't afford to have smell just wandering out of the intake because the pressure is too low...That would defeat the purpose of a stealth box lol!

Thanks as always!

Come on, that's like getting a puppy and keeping it in a 5 gallon bucket. You can't hollow out a dresser or closet or use anything more than 2 feet tall? By the time you add a light and dirt, they'll barely be room for a plant.

tibberous said:

Come on, that's like getting a puppy and keeping it in a 5 gallon bucket. You can't hollow out a dresser or closet or use anything more than 2 feet tall? By the time you add a light and dirt, they'll barely be room for a plant.

Click to expand...

It's not for a living plant man

I think you just hook up an exhaust fan at the top, run it to a carbon filter, and put a couple holes in the bottom. It's going to suck in air, if you made it airtight, it would be a mold box, and smell like mold (although only when you opened it) Dunno how much your drying, but you might be able to use these as cheap shelves (http://www.ebay.com/itm/Mainstays-Home-Sweater-Drying-Rack-Folding-Mesh-Hanging-Clothes-Flat-Dryer-Net-/350643155527?pt=LH_DefaultDomain_0&hash=item51a3f5f247)

Keep in mind, if your using a ductable fan, there rated for rooms / tents much larger than that box. If you create too much outflow, it will be like putting your bud in a food dehydrator. Drying nets typically take 4-5 days and even then then it's not super-dry. Maybe get something like this and use a dimmer / fan controller to adjust the speed? http://www.homedepot.com/h_d1/N-5yc1v/R-100073963/h_d2/ProductDisplay?catalogId=10053&langId=-1&keyword=4"+duct+fan&storeId=10051#.UKsHb4ZNedA

ive done this with an exhaust fan and a passive air intake. I made the intake adjustable and no, you wont need to seal the top, the air will go the least resistant path. even if you drill holes to knot the string through you'll be fine. i liked the closet+coathanger method more tho. edit: passive air will let smell out but wont make it a less smelly end product. if your'e worried about odor then yes, you need to seal your box. this means figuring out how many times the air should be refreshed per hour and then meeting it. It also means having everything airtight with a carbon filter. if the exhaust creates enough negative pressure the smell shouldn't permeate as bad

Thanks for the posts guys. Let me tell you how I'm planning on setting it up, so that there isn't any more confusion.

This will be in a temperature, and humidity controlled room. The box will have holes drilled/poked through, and I will be running string across like this: View attachment 2415980
Then I will seal up the holes with hot glue, and cut off the excess string. I plan on running only one 120mm fan @ 69CFM & 20dB, and would like to keep it that way. It will also be pulling the air through a filter like this: https://www.rollitup.org/attachments/cfl-fluorescent-lighting/559554d1253894626-pc-case-fan-3inch-dyi-box-02.jpg So, I believe that the fan I will be using will be more powerful than the one that was shown in that thread. So, I don't think it will be straining to keep up on the scrubber.
P.S. I will be sweating them in a different container.

I'm not so worried about losing the dank smell, (although that's a plus ) But, it's the escaping odor I can't afford to deal with. So, I'm mainly asking for help how to figure out how to get the right amount of negative pressure to keep scents contained. Running on a system of 1 pc fan, and that carbon scrubber I linked.

Also, when I calculated the cfm, and checked it with a grow space cfm calculator, for a box that's 3 x 2 x 2,to fully exchange air every minute, I have to have 7 CFM's is that accurate? But again, I'm mainly asking for help how to figure out the right amount of negative pressure, and right size intake to keep all scents contained.