Axial (PC Fan) Vented Growbox's

[phr3d0m2gr0]

If your cabinet/grow box is vented strictly by axial or PC Fan's could you post up some pictures and give a quick explanation/review of how it's working. This is for ventilation not for cabinet's with just a PC Fan for circulation around the plants.

I'm thinking of building a couple of boxes and I would like to try to use just axials to be as quite as possible. The only problem is I'm not sure how to setup odor control.

Looking forward to pics!

-Phr3

 

[SativaDreams]

I'll post my pictures when I get new batteries for my camera.. I just installed a 34 cfm axial PC fan in my 2 x 2 x 1 foot dresser..

I'm currently not growing anything but I am doing temperature tests.. right now testing without fans, then with fans.. then with lights on .

I don't know how well it will cool, but I'm pretty excited either way, it's one outtake fan and no inputs (2 x size passive intake)
I'll let you know

 

[DarkLance]

120V Axial Fans

120V Axial Fans

I got my hands on three 18W 120V axial fans and one 36W'r


I have a dr80 tent and I use 6" duct to exhaust it (even though the holes are 130mm[5in]).


What I did with the duct is to cut it, then attach the ends to either side of the fan with duct-tape (and gorilla tape in key locations for strength). This makes the axial fan into an inline fan. Turns out both fans are more than powerful enough to create negative pressure, so I cut the 36W out and use only one 18W.

The fans have two power leads, neither is distinguished from the other. I am not sure if the load & neutral(sorta like dc polarity) matters, the fan does not appear to run different in either configuration. My assumption is that the transformer handles the issue. I did not wire the ground, do so at your own risk

 

[FreezerBoy]

While axials move the most air unimpeded, they move the least air when forced to deal with back pressure such as scrubbers. I used a 76 cfm axial that could handle a DIY odorsock but, the odorsock was VERY limited in what it could handle. The carbon filter pads got me through half a Destroyer grow, the remaining pads finished the grow. But, my 8Mile over whelmed the odorsock on day 3 of a 90 day flowering period.

Maybe SugarBears MicroScrubber is for you.

 

[phr3d0m2gr0]

DarkLance: Do you you have two 18W fans inline with each other?

FreezerBoy: After reading through the Ventilation 101 thread by redgreenry, it seems that you can do a couple of fan's inline and this will help build up negative pressure. I think doing this would allow the use of a more robust carbon scrubber, but certainly nothing like a can filter.

 

[FreezerBoy]

phr3d, thanks for watching out for me. In a smaller enclosure, that might be the way to go. I went with an S&P mixed vent. Now where near the sucking power of a centrifugal but, nowhere near the noise either. Handles my new DIY can filter well.

The 4" S&P has a 6" dia whereas a 4" Vortex has a 12" dia. I could afford to surrender 6", no way would I have surrendered a foot.

 

[solarz]

While axials move the most air unimpeded, they move the least air when forced to deal with back pressure such as scrubbers. I used a 76 cfm axial that could handle a DIY odorsock but, the odorsock was VERY limited in what it could handle. The carbon filter pads got me through half a Destroyer grow, the remaining pads finished the grow. But, my 8Mile over whelmed the odorsock on day 3 of a 90 day flowering period.

Maybe SugarBears MicroScrubber is for you.

Freezer Boy...do you run your 8 miles high to 90 days? Or am i reading that wrong...or were you simply referring to something else? I'm asking b/c i run 8MH (from Mandala) and i read (as well as acted on it) that it was to be taken WAY earlier than 90 days. Like 60...?? Just thought i'd ask.

thanks in advance,

solarz

 

[ScrubNinja]

I'm nearly done constructing a cab that uses 4 x 120mm 12v pc fans inline. Check out my thread as it's way too long to explain here, but I did some heat runs and posted them up, where I blocked 4 of the 6 intakes to loosely simulate a carbon filter. Should have the carbon filter finished in the next couple of days if you want to look in then. It should give you an idea of what to expect anyway. In a way, I've actually built a powered carbon filter, so the whole grow section is passive.



In my opinion, (almost) forget all about CFMs when deciding on axial 12v pc fans for carbon scrubbers. The scrubber is a restriction and if you restrict a pc fan by resting it on the ground blowing upwards, how much does it blow? Pretty much zero which is all the good CFM ratings will do you without paying attention to the important ratings.

"Pressure" usually measured in mm-h2o indicates exactly what we need to know; how well it is going to push through a scrubber. You could have a 1000cfm fan, but it's not gonna do anything if you have no pressure. Sure it's a good idea to look at the CFMs at this point once you have verified it's got a good amount of pressure.

The Amps rating will also give you a good general idea of how strong a fan you're dealing with.

 

[FreezerBoy]

Freezer Boy...do you run your 8 miles high to 90 days?

D'oh. Ya got me. I transposed numbers in my head. 60-65 days of 12/12 after 30 days of veg for 90 days total. Still, they stunk real good real fast and my little odorsock was helpless. Maybe if I'd wrapped it in double/triple layers ...?

 

[camo]

These fans can vent up to about 250watts max

These fans can vent up to about 250watts max

These delta fans are a bit rare but are some serious fans.

Model number is the big number in the first pic

Hook em up to a 12 volt adapter. With these fans speed and voltage run together. To adjust speed either hook up these fans to a lower voltage, 10,8,5, or run a rehostat of some kind to lower the speed/voltage with a switch. For silence build an insulated box around it and push though a bit of insulation and handymans cloth. They can stand up to the heat of long term pulling through a filter a and light since there designed to cool server equipment.

On a side note these types of fans rarely just die. They will usually give one advanced warning through squeaks and clicking giving you lots of time to replace it.

 

[phr3d0m2gr0]

These delta fans are a bit rare but are some serious fans.

Model number is the big number in the first pic

Hook em up to a 12 volt adapter. With these fans speed and voltage run together. To adjust speed either hook up these fans to a lower voltage, 10,8,5, or run a rehostat of some kind to lower the speed/voltage with a switch. For silence build an insulated box around it and push though a bit of insulation and handymans cloth. They can stand up to the heat of long term pulling through a filter a and light since there designed to cool server equipment.

On a side note these types of fans rarely just die. They will usually give one advanced warning through squeaks and clicking giving you lots of time to replace it.

That thing looks crazy! I searched around for it, about $45 or so for a fan and they ship very slowly. It got me searching around computer building sites though for fans and there are quite a bit out there. Anyone have any particular favorites?

When I was into computer building I usually order from these three sites:
xoxide.com
zipzoomfly.com
newegg.com

They all seem to list the noise level and cfm of the fans. Sometimes even the mm H20, which is useful when thinking about scrubbers.

-Phr3

Edit: I found this chart which may be kind of useful for comparing the dB levels of fans to other objects.

Sounds.....................................................dB
Rocket Launching..........................................180
Jet Engine....................................................140
Thunderclap, Air Raid Siren 1 Meter...................130
Jet takeoff (200 ft)........................................120
Rock Concert, Discotheque..............................110
Firecrackers, Subway Train..............................100
Heavy Truck (15 Meter), City Traffic...................90
Alarm Clock (1 Meter), Hair Dryer........................80
Noisy Restaurant, Business Office.......................70
Air Conditioning Unit, Conversational Speech........60
Light Traffic (50 Meter), Average Home...............50
Living Room, Quiet Office..................................40
Library, Soft Whisper (5 Meter)..........................30
Broadcasting Studio, Rustling Leaves...................20
Hearing Threshold.............................................0

Edit Again: And another chart from redgreenry's thread "Ventlation 101":

 

[phr3d0m2gr0]

Here's a link to check out grainger's line of axial fans. They have quite a bit of variety and have plenty of fans that are 115V.

http://www.grainger.com/Grainger/wwg/productIndex.shtml?L2=Axial&operator=prodIndexRefinementSearch&originalValue=dayton+axial+fans&L1=Fans%2C

I'm also starting to look around for fans for my next build and here's some interesting one's I've come across at the 120mm size:

• http://www.newegg.com/Product/Product.aspx?Item=N82E16811999127
• http://www.newegg.com/Product/Product.aspx?Item=N82E16835226013
• http://www.newegg.com/Product/Product.aspx?Item=N82E16835103061 (This one is especially enticing with a fairly low price tag and a 5.5 year rated lifespan)
• http://www.xoxide.com/thermaltake-120mm-cat-fan.html

-Phr3

 

[ScrubNinja]

Check my sig now bro, there's a good discussion on these. The 120s you listed are very weak. It depends on the level of stealth needed though. If you can afford to make some more noise, there are much better choices.

 

[phr3d0m2gr0]

Thanks ScrubNinja. I had searched early but didn't find your thread that's why I created this one. For anyone reading this in the future head to ScrubNinja's thread instead:
http://www.icmag.com/ic/showthread.php?t=131842

-Phr3

 

[geopolitical]

Here's one with two 80mm fans with thermal resistors placed at the base of the socket & in the ballast to regulate temp.

It's been working fine for 4+ years now.

Here's the front.

Here's a construction photo showing the fans & filters (carbon mesh in a filter housing is replaced every week or so. A universal carbon filter replacement sheet from the hardware store lasts me months.)

 

[phr3d0m2gr0]

Very interesting setup geopolitical. Would love to know how you wired up the resistors.

-Phr3

 

[geopolitical]

I couldn't tell you the ratings of the resistors even if I could remember clearly that far back. I know they'll let the fans run full open at around 40c (remember, the resistors are placed by the ballast core & the bulb socket) and to nearly nothing by the time you drop down to 15c or so.

It was a very simple wiring job. I just cut the positive line to the fan, soldered in the resistor with a decent amount of wire, heat shrunk everything, and that was it.

You just need to find a thermistor (thermal resistor, etc) that has a rating that will work for your project. For instance, if you wanted to locate the thermistor at say, canopy level, you'd want to pick one that drops to zip resistance just above your target temp, so as temps rise, the fan keeps pace.

This is not an exact science and I think I tried out two or three fans before settling on the models installed. Some fans do very poorly at the reduced speed, some do well. I recommend testing such a system before committing to it.

 

[phr3d0m2gr0]

Ok sweet, I thought it might be that simple. I played around with some thermistors in a college electronics class and I was definitely interested in doing more sensor work. I think I'll start looking around for thermistors now, just to play around with.

-Phr3

 

[ScrubNinja]

The Thermaltake Smart Case Fan II I use has a thermostat feature except the range is set at 20 to 55 celcius. So at 20c the fans are at minimum, then slowly ramp up speed to 55c where they're on full. The sensor can be thermal-taped to a bulb etc and shifted around to find the perfect placement and that's pretty much your adjustment knob. I'm yet to use it in a cab but I think it has potential.

I just found this online which could make it more user friendly:

While using the fan I discovered a few things about these two different options. If you choose to use the thermal sensor, then your fan speed is going to be relatively low and cooling will not be that great. If you hook up the analog fan speed controller then you can control the speed of the fan by hand, but the cable isn't very long, so it would have to be mounted in a PCI card bay or maybe in a hole in the back of the case, which would take some effort. However, if you hook up both the analog controller and the thermal sensor, you can control the fan speed manually and whatever speed you set it to, the thermal sensor will adjust the fan about 100 or 200 rpm faster or slower, depending on how much heat is being detected. However, if you set the analog fan speed modifier to full speed then the thermal sensor will do nothing because it cannot push the fan to go any faster if it detects extra heat, so the thermal sensor becomes useless if you are running the fan at the full 5400 rpm.

 

[phr3d0m2gr0]

The Thermaltake Smart Case Fan II I use has a thermostat feature except the range is set at 20 to 55 celcius. So at 20c the fans are at minimum, then slowly ramp up speed to 55c where they're on full. The sensor can be thermal-taped to a bulb etc and shifted around to find the perfect placement and that's pretty much your adjustment knob. I'm yet to use it in a cab but I think it has potential.

I just found this online which could make it more user friendly:

So the smart case fan comes with it's own analog controller? Do you have this wired into your grow? If this is true then I may want to try to use these, it would be nice to make a panel of controllers for different fans. Would help get everything dialed in quickly.

-Phr3