Kifthief''s NEW Cfl Server Grow

[KifThief]

Hey guys, I am moving my grow from my speaker case to a new server case I picked up. The dimensions are about 20x20x10 inches, and it was free there was a computer place down the street that was closing down, and the manager just let me have it. I am going to use the power supply to run 5 80mm fans, 3 exhaust and 2 intake.

I am sort of stumped on the filter though, do you guys think the fans would be able to blow through some carbon prefilter material? ( http://www.iallergy.com/product228/product_info.html )

Oh, and the best part is the case has a built in lock

 

[Crake]

One of the PC growers was under the assumption using that pre-filter material would be enough. I can't remember the thread but it didn't work at all and he ended up fabricating a scrubber out of some steel mesh or something.

The problem with scrubbers is that they require about an inch of carbon to absorb the odor, and a regular PC fan can't push or pull air through an inch of carbon that's only, say, 120mm square. You just need to have more surface area.

I would kick around the idea of making a 1 inch thick reservoir of activated carbon that's 20 inches tall and 10 inches deep that slides into the back of your case, then pull the air through that entire sheet and out the back, like this:

@ = fan, * = carbon

____________
@.*........|
@.*........|
|.*........|
|.*........|
|.*........|
|.*........|
|.*........|


Unfortunately you'd be losing about 3 inches of depth to your case, but you wouldn't have odor issues--there would be enough surface area for the static pressure those shitty PC fans create to pull the air through.

Also, scrap your intake fan idea, you'll just be creating higher static pressure inside the case and end up blowing a lot of unscrubbed air out of air leaks. Use some passive intakes totaling twice the surface area of your outtakes.

 

[KifThief]

Hmmm, makes sense to me. Do you think three exhaust fans would be enough though? plus another problem is that im using a computer power supply, which obviously includes a fan.

What would you think of the idea of having two fans to pull air through the filter/reservoir and somehow creating ducting to run from the power supply to outside the case to keep it nice and cool?

Ive also been toying with the idea of just using odor-absorbent gel. Ive heard of people using this in their micro grows with some (seemingly) good success, but what is your opinion on that? Or any other forms of odor control?

 

[Crake]

It's hard to say what would be enough because there's no real way to know what the actual CFM of the fans will be after adding all that drag from the scrubber. But I feel pretty certain having an upright layer of carbon like that with your two or three fans would get you enough surface area to keep it cool enough to grow inside there.

With regards to the ducting, I think anything you can do to isolate heat from the growing space is a smart idea. I don't know why you're using a power supply though--those things get hot. If it's for the fans, you ought to just grab a transformer with enough amps to power your fans. (Your fans will say, like, 0.8A. You'd need to get a transformer that outputs enough Amps that the sum of the all the fans amps would be less than or equal. E.g. if you had three 0.8A fans, you'd need a transformer that outputs 2.4A to power them all at full speed.) You can grab transformers at thrift stores or whatever, and they don't produce nearly as much heat.

Odor-absorbent gels, kitty litter crystals, etc only mask the smell with a more overpowering odor. Carbon is the only way to go in my opinion.

 

[KifThief]

What about forgetting the dc fans and just shooting for this?

http://www.homedepot.com/webapp/wcs...googlebase-_-D26X-_-100073963&locStoreNum=175

That way i could get rid of the power supply, and not worry about the other fans and push air through some activated carbon. It will definately take up a good amount of room, but compared to having a power supply and an entire section of my box occupied by a carbon screen, I feel like it could be pretty low profile.

Let me know what you think

 

[KifThief]

If i were to use the duct fan this is some mock-up of how i would set it up, its not proportional, but i think it would work and fit, assuming the fan performs well dealing with the pressure of pulling air through the carbon


Let me know what you think

 

[microbox]

I would use fans only for exhaust, and that one is junk. They make AC PC fans that plug right into the wall so you dont have to deal with a power supply.

 

[microbox]

I just seen your drawing. Its best to have yuor exhaust on the top besides heat rises.

 

[KifThief]

i know heat rises, but like i said the picture is not proportional, so the filter would actually be drawing air from the top of the box. and the way my pc case is configured, theres pretty much no other space-saving configuration i could use with a fan that big

the problem with a/c pc fans is they dont deal with pressure well enough to pull air through a carbon filter efficiently

 

[Crake]

What about forgetting the dc fans and just shooting for this?

http://www.homedepot.com/webapp/wcs...googlebase-_-D26X-_-100073963&locStoreNum=175

That way i could get rid of the power supply, and not worry about the other fans and push air through some activated carbon. It will definately take up a good amount of room, but compared to having a power supply and an entire section of my box occupied by a carbon screen, I feel like it could be pretty low profile.

Let me know what you think

I think that's a decent idea, but that inline is going to sound like a helicopter. If you used something like a whisperfit 50 you might be able to get the kind of air pressure you need to pull through a tiny scrubber like that. It would still sound like a jet engine.

Believe it or not you're treading into some pretty new territory. By now you've probably spent a lot of time researching PC case grows on the forums and realized that there are almost no cases that completely achieve the following four desired characteristics: masked odor, growable temperatures with desirable lighting, unnoticeable sound levels, normal appearance. Nearly every case on the forums that I've seen makes sacrifices on at least one of the four.

A tiny sugabear scrubber like the one in your design is just not going to work (I don't even think it worked for sugarbear, if I remember correctly--he later scrapped it I think? It's been a while since I read that thread). By all means, spend time figuring that out on your own--I know I did. In fact I ended up making a pretty great micro scrubber for my PC case that kind of worked. I still had to make significant sacrifices to lighting inside (23W eventually, I think) and still had temperatures that were 12-15 degrees above ambient. It was fun as hell engineering the case, but it only ended up being a fraction of what I wanted it to be. I was happy to scrap it and chock it up to lessons learned.

If I were to do it all over, I'd do exactly what I drew out up above. It's so damned simple and easy. A layer of easy to make, easily changeable carbon. Something I could slide out quickly, change the carbon and slide back in. No disassembling cylindrical scrubbers for carbon changes or whatever. Maybe stick some reflective material between it and the plants. I feel like I'd be able to throw 100 watts into a case that size no problem with three output fans sucking through that carbon because the drag would be so little. Not to mention I'd really be sacrificing relatively little growing space.

the problem with a/c pc fans is they dont deal with pressure well enough to pull air through a carbon filter efficiently

P.S.: PC fans are perfectly capable of pulling through carbon of adequate surface area. A 50CFM PC fan that is only obstructed by 20% would still be pulling 40CFM, which is a ton of air changes for a 10x20x20 box.

 

[KifThief]

hmm, that seems do-able.

but how should i go about making it airtight against the walls and the the door?

 

[Crake]

hmm, that seems do-able.

but how should i go about making it airtight against the walls and the the door?

Weatherstripping. That hollow rubber stuff works well for getting a snug fit. You could also make a frame for it with some 10" sticks/rails/something fastened to the case like this:


* = frame, @ = fans, || = carbon layer
________________
@.*||*.........|
@..||..........|
|..||..........|
|..||..........|
|..||..........|
|..||..........|
|..||..........|
|..||..........|
|..||..........|
|_*||*_________|

So it could just slide in and out in an exact place. Just an idea.

 

[HighDesertJoe]

What about forgetting the dc fans and just shooting for this?

http://www.homedepot.com/webapp/wcs...googlebase-_-D26X-_-100073963&locStoreNum=175

That way i could get rid of the power supply, and not worry about the other fans and push air through some activated carbon. It will definately take up a good amount of room, but compared to having a power supply and an entire section of my box occupied by a carbon screen, I feel like it could be pretty low profile.

Let me know what you think

You guy's think you can hook this fan up with like a dimmer
switch? I don't need a scrubber

 

[KifThief]

Im starting to really like that idea, Crake, thanks so much for the advice. Im going to build the frame of the filter out of wood and sort of modify the idea of having the sliding screen, im going to build a frame on the inside that the filter could couple up with. Pictures to come

 

[The Hummus Monk]

This sounds interesting!

I have built a cab about 30x25x20 hxwxd and have 4 pc fans in a cube as in diagram above. I've used right angle guttering elbows pointing downwards from the fans/holes outside the box.

To scrub I was going to suspend beneath each bit of guttering pipe a bit of stocking material with carbon in.

Hmmm...screen idea sounds good too!

I have 3x105w cfl's in there

 

[Sgt.Stedenko]

For a PC/server case, one exhaust fan is all that's needed. DO NOT use intake fans. Just have twice the intake area of the exhaust (i.e. one 4" dia. exhaust = two 4" dia. intakes) like Crake said.
Put the exhaust fan and scrubber on top exhausting out the PSU opening. Get one large CFL bulb (65w-105w) and place it parallel to the scrubber on top.
Intakes are best placed on the bottom floor of the case. Get a small screen and elevate it no more than 1" off the floor. This is what your grow container will rest on allowing cool air to enter from beneath. Cover the intakes with the carbon pre-filter to keep out nasties. You may have to build a small light baffle to keep light leaks down. Foamcore, white glue and foil tape will suffice for a DIY baffle. Paint the inside black to absorb light.
Ditch the PC power supply and use a DC wall transformer. The less voltage you throw at the PC fan, the slower it spins. A 12v transformer will run at full speed. A 6v unit will run less. I wouldn't go below 6 since you are trying to scrub as well.

 

[KifThief]

Well heres what I did for the filter:

Im using it as a partition between where the plants are going to be and where the electronics are. I have it set up so each chamber is sealed off and lightproofed. Air flows pretty well and the temps seem to stay pretty low with the lights on, im going to let it stay on for a few hours and leave a thermometer in there to see where theyre at

 

[Crake]

Well heres what I did for the filter:

Im using it as a partition between where the plants are going to be and where the electronics are. I have it set up so each chamber is sealed off and lightproofed. Air flows pretty well and the temps seem to stay pretty low with the lights on, im going to let it stay on for a few hours and leave a thermometer in there to see where theyre at

Looks alright man. Let us know how your temps turn out, huh?

If you're thinking you're airtight, a good test is to throw a bottle of vanilla extract in there with the cap off and see if you can smell any odor coming out of the fans.

 

[KifThief]

Ive actually done alot since i took those pictures, ill post new pictures when im done light proofing and everything

 

[Crake]

Ive actually done alot since i took those pictures, ill post new pictures when im done light proofing and everything

Rad. Can't wait to see how it's turning out.