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Leeguana
08-01-2008, 01:38 AM
We had a microwave that died a few years ago, and today I decided to experiment. I pulled out the fan, connected the two wires coming out of it to an old lamp cord, plugged it in, and voila, it works!

I've been looking for a cheap exhaust fan for my grow cabinet (4'H x 2.5'W x 2'D) and I'm wondering if this just might work. The fan blade is only 4.5" across, but the whole thing must weigh close to 2 pounds. It blows like a mini-jet propeller, and from googling the CFM of microwave fans, it's probably pushing around 200 CFM.

Does anyone have any experience using a microwave fan for their exhaust? From reading on ROI, I've got some pretty decent ideas for a DIY odor control filter, but any tips on how to mount the fan would be greatly appreciated (since I'm severely challenged in the area of electronics). Are there any safety issues I should be concerned about? (for example, when I plug it in, I'm afraid to touch any part of the motor, for fear of being electrocuted, lol). Here's a couple pics of the fan (the 3 screws on the back are where it was mounted inside the microwave):

anbesol
08-01-2008, 02:25 AM
i would say fuck it and buy yourself a real fan. You will probably end up starting a fire with that or electricuting yourself like you mentioned before.

Leeguana
08-01-2008, 02:34 AM
i would say fuck it and buy yourself a real fan. You will probably end up starting a fire with that or electricuting yourself like you mentioned before.
Yeah, lol, I was actually more worried about burning down the house than self-electrocution. It's just that this little baby pushes so much air, I hate to let it go to waste. :stoned:

TheMetal1
08-01-2008, 04:34 AM
I hate to let it go to waste. :stoned:

Yeah, wasting parts from an old junk microwave really sucks...........
unless it ensures you'll never come home to a local fire dept. tutorial on how to put out an electrical fire :wtf:

I would suggest you either:
1) Do a lot of reading or watch videos on wiring
2) Wait for an expert to come blow your mind w/ a simple solution
3) Buy a new fan (my favorite :thumbsup:)

Not saying you can't wire up a fan, but considering you are afraid to touch any part of the fan/motor might be an indication that you should go w/ door #2. Have fun!
Stay :D Keep :jointsmile: and Be safe :hippy:

Leeguana
08-01-2008, 05:24 AM
I personally like option 2 the best since it's the easiest, but that probably won't happen:). I might shoot for option 1. Just to satisfy my curiosity, maybe I'll waste a little money on some ducting and try to rig something up.

Since the screws on the back of the fan that attached it to the housing of the microwave were exposed, I probably won't get jolted with juice. But maybe I'll try plugging it in again, and then toss a live ant or some other bug on it and see if it survives, lol.

I think I can shape a metal bracket, screw it onto the back of the fan (using the holes and screws where it was originally attached to the microwave), and then attach the bracket to the inside ceiling of the cabinet up against the exhaust hole.

Then affix a piece of ducting over the whole thing (for the "housing"). And on the outside/top of the cab, I'll have to cover the exhaust hole with screen or something so no one gets their fingers caught in the fan blade, lol.

I'll definitely post some pics if I do this, cause if nothing else, it should be a "unique" looking exhaust sytem.

stinkyattic
08-01-2008, 02:48 PM
You're lucky as shit that fan is directly connected to a transformer, and you got the whole thing... It's STILL not grounded right, though.

Get a real exhaust. Seriously. That thing is not only a fire hazard, but uncaged fans are DANGEROUS. International Cannagraphic Magazine Forums - The perrills of uncaged fans....lol (http://www.icmag.com/ic/showthread.php?t=95489)

TheMetal1
08-01-2008, 02:55 PM
That thing is not only a fire hazard, but uncaged fans are DANGEROUS. International Cannagraphic Magazine Forums - The perrills of uncaged fans....lol (http://www.icmag.com/ic/showthread.php?t=95489)

LOL @ unintentional grow room security. :stoned:

Leeguana
08-01-2008, 07:14 PM
I better get a real fan after this grow is done (assuming the house doesn't burn down). They've only got about 3 weeks left in flowering before I harvest them.

I ended up not making a carbon filter yet, since the wife said I could use our room air purifier (it's got a carbon filter, a hepa filter, etc.). It takes care of the smell unless you are standing right next to the cabinet.

I just took some scrap sheet metal from the bottom of the junked microwave, cut a couple pieces to size (I bolted the two pieces together to make a double layer cause the metal didn't seem very sturdy), drilled holes in the metal, and screwed the fan into it. I was going to cut a round hole in the top of the cab for the exhaust, but since this is a temporary fan, I just attached the fan to the hole on the side/top. There's another hole just like it on the side/bottom. I built this cabinet back in the early 90's and kept my Iguana (Joe) in it, so it already has two vent holes (except they're both on the same side of the unit, and they're rectangular shaped, covered in 1/2" wire mesh).

The temp was reaching 90+ and I was having to leave the door open a bit to keep them cool, but with the fan installed, the temp is now topping out at 80 degrees.

Note to self: Get a real exhaust/scrubber system, and remodel lizard cage so it's more suitable for growing.

SAP420
08-02-2008, 01:16 AM
Look man, there is a right way to do things and a wrong way. I'm not one with lots of money either but I would rather purchase a fan filter combo which you can get for less than $200 if you shop around..htgsupply.com. hint hint. I don't think its worth the risk of using a fan that is not designed for what you are wanting to use it for. Plus duct fans are specially designed for perfect airflow to get that hot air out as fast as possible while providing a good suction of air to come in. I just bought everything little by little and now my setup is as follows:

1 HPS 400 watt S51 type ballast with reflector and bulb.
1 3x3x6 hydrohut mini
1 170 cfm inline fan with elf filter scrubber
4 GH waterfarms
1 sunleaves 4 outlet air pump for lift systems
4 single air pumps for reservoir airstones
floranova grow
floranova bloom
6" clip-on fan for air movement on plants (still on the way)
1 heavy duty digital appliance timer for fan and light

Leeguana
08-02-2008, 03:57 AM
Sounds like you've got a super sweet operation going on there Sap, I'm jealous. But like I said, I've only got like 3 weeks until harvest, and then I'll be doing some upgrading. This is my first grow and I didn't feel I had the knowledge to justify spending a lot of $ in case things didn't work out.

I didn't really pay for anything in my setup, since it was all stuff I already had (except for CFL's, some light sockets, and a $5 bag of soil). I admit I'm a bit of a cheapskate, but I also kind of get off on the DIY way :).

I'll definitely be changing things up in 3 weeks, but there is NO WAY I'm gonna spend anywhere even close to $200 for a fan filter combo. Maybe $20 or $30 for an inline fan, and probably about the same for a DIY carbon filter. I'll spend the leftover cash on more and better lights, since I can't make those from things laying around the house. :rasta:

Let me know if you starting a grow journal, I'm very interested to see what the hydrohut setup looks like.

PottyBear
08-02-2008, 08:08 AM
OK, honestly, I HAVE to ask. Am I just getting REALLY damn old or does $200 for ANYTHING, particularly a simple hobby-type grow like this, sound absolutely RIDICULOUS? Am I the only one? Anyone? Bueller?

$400 is NOT cheap unless it is a car.

$200 is NOT cheap unless it is a major appliance.

$100 is NOT cheap unless it is a 27" television.

$50 is NOT cheap unless whatever it is is going to perform sexual favours all night long.

I am completely amazed at how people here seem to think that whipping out $200-500 for individual items to grow a few plants is somehow economical. If I am growing for medicinal purposes, it isn't making me any money, and EACH of those items at that price would buy me a couple months worth of stuff at the rate I need. Seriously - who has this kind of money to just pull out and spend? That's groceries for a family of 4 for a week or two.

Now, that said, your fan probably does not run on 110V and that is why the transformer is on it. If the transformer had been elsewhere in the case, the odds are you would have already had need of a fire extinguisher unless you were REAL lucky and it just fried and died fast leaving that wonderful ozone-burnt-circuit smell.

I'm all for MacGyvering things if you know what you are doing, and I do stuff like that all the time. But, that's a shock hazard if you touch certain parts on the transformer, and throwing a bug on it won't tell you squat. Microwaves have ground plugs for a reason - to stop the electricity from going through YOU and instead into the ground in case of a fault. A bug on the transformer or fan motor would not be providing a path to ground like you would when you pick it up, so its survival means nothing. That fan attached to metal and not using a 3-prong plug to ground it gives me visions of you coming back here one day telling us you now must use speech recognition software to write your posts because you fried your fingers when a fault developed in that transformer. Mmmm. Crispy, burnt flesh smells. That's subtle. I'm sure that it won't get anyone's attention.

IF you are really determined to use it, and I am not saying it is a good idea, you need to make a box out of a non-conducting material, AND you need a 3-prong plug with a wire connected to a ground location on that assembly (such as where the bolts connected it to the MW chassis - possibly - hard to tell from the pics).

It is only 50cfm (but I have a small space), but a small bathroom exhaust fan only costs $20 and it is HELLA safer to wire up to a plug (although I'd still use 3 prongs to be safe). It is also square which means it is easy to rig up any number of different things for filtering (like using the air filter you are thinking about, or cutting up an odour-controlling furnace filter or blowing it through a box of aquarium charcoal or SOMETHING)...

I'm not going to say I am an expert, but I used to work as an electrical contractor's assistant, I've rebuilt dozens of electrical motors (including fans) and power supplies, and I have a lot of experience working with both AC and DC-powered items.

All I can say if you won't listen to anyone is that I hope you have neither kids nor pets - at least none that you value.

tinytoon
08-02-2008, 10:34 AM
you can get a 4" inline fan from Home Depot for about 20 bucks and it sits right next to 4" duct work in there heating isle, can regulate speed with a dimmer switch same as done in the DIY dryer box

SAP420
08-06-2008, 10:57 PM
I just have to say that it is alot smarter to invest in your own shit rather than buying your smoke from the streets where you have no idea where it has been plus you know what is in your plants. It really does save you money in the long run. Especially if you grow hydro cuz hydro is hella expensive shit when you buy it on the streets. And no worries about flakey drug dealers chincing on your stuff and taking you for your money plus trying to find someone who is reliable on supply. We got stuff one time that smelled like gasoline straight up. Just can't trust anyone nowadays especially in the U.K. with ppl putting pieces of glass in the weed to fool ppl into thinking its good stuff. Just safer to grow your own.. and if you do grow your own, isn't it worth it to put the best effort forward into getting good results????

stinkyattic
08-07-2008, 01:57 PM
OK, honestly, I HAVE to ask. Am I just getting REALLY damn old or does $200 for ANYTHING, particularly a simple hobby-type grow like this, sound absolutely RIDICULOUS? Am I the only one? Anyone? Bueller?

With the $2,000 you spend on enough gear to set up a very very good hobby-sized grow appropriate to about a 5x5 footprint, properly lit and ventilated, that will grow you a POUND of the finest herb you have ever smoked every 2 months...

Yeah. It's cheap. I get fabulous prices for my area and I'm paying $2600 for a pound of Canadian imports. And their medicinal value is debatable... I don't know how they were grown, but I assume in all cases that warehouse crops are treated with floramite.

If you go through a pound a year, which is 1.2g a day, or about a quarter-ounce a week, you get your investment back probably close to ten times over the first year. If you are averaging about $350 an ounce for medicinal grade stuff, you're throwing money away by not growing your own.
Your FIRST HARVEST under a 1000w lamp should yield you, CONSERVATIVELY, 600 grams, or 21 ounces. That's at the 0.3 multiplier; experienced growers use 0.5.

21 zips. for which you'd be paying $350 each, are worth $7350 when you're done, or if you are buying QPs at a time, you MIGHT end up spending $5k on the pile. If you're lucky.

Subtract out the $2000 you spent on your lights, media, fans, and nutes, and you realize that you have saved between $3k and $5k- JUST FROM ONE CROP.

"Bueller" says... it's worth it. Good gear is the difference between a failed harvest and a bumper crop.

It's called investment, but what do we know about that?
Originally Posted by PottyBear http://boards.cannabis.com/images/buttons/viewpost.gif (http://boards.cannabis.com/growing-information/159336-contradictions-seriously-wtf-2.html#post1892006)
I know - you're a bunch of stoners, I should not expect much in the way of comprehension, right?


I'm finding the rants entertaining, BTW.

SAP420
08-08-2008, 05:28 AM
Yeah... people that rant on here are bunch of pissy winey bitches who need to appreciate the fact that such a board as this exists. Its not like they have to pay to be a member and most of the ideas and suggestions that I have come across thus far have been very good ones. Granted everyone has a particular way they grow but if it worked for them then there is no reason why they can't share their successful methods of growing the finest herb. I wish I had become a member of this board a long time ago cuz there is so much I have learned on here as well as possibly helped others to become great gardeners. I kinda played it by ear the first time around and off of my 400w hps I was able to get damn near 3 oz. off my first grow and that was just one plant. So I am eager to grow over and over again. So thanks to Stinky and everyone else that has been so eager to help others in this great learning experience! :thumbsup::D:hippy:

Testament
08-08-2008, 06:09 AM
With the $2,000 you spend on enough gear to set up a very very good hobby-sized grow appropriate to about a 5x5 footprint, properly lit and ventilated, that will grow you a POUND of the finest herb you have ever smoked every 2 months...

Yeah. It's cheap. I get fabulous prices for my area and I'm paying $2600 for a pound of Canadian imports. And their medicinal value is debatable... I don't know how they were grown, but I assume in all cases that warehouse crops are treated with floramite.

If you go through a pound a year, which is 1.2g a day, or about a quarter-ounce a week, you get your investment back probably close to ten times over the first year. If you are averaging about $350 an ounce for medicinal grade stuff, you're throwing money away by not growing your own.
Your FIRST HARVEST under a 1000w lamp should yield you, CONSERVATIVELY, 600 grams, or 21 ounces. That's at the 0.3 multiplier; experienced growers use 0.5.

21 zips. for which you'd be paying $350 each, are worth $7350 when you're done, or if you are buying QPs at a time, you MIGHT end up spending $5k on the pile. If you're lucky.

Subtract out the $2000 you spent on your lights, media, fans, and nutes, and you realize that you have saved between $3k and $5k- JUST FROM ONE CROP.

"Bueller" says... it's worth it. Good gear is the difference between a failed harvest and a bumper crop.

It's called investment, but what do we know about that?
Originally Posted by PottyBear http://boards.cannabis.com/images/buttons/viewpost.gif (http://boards.cannabis.com/growing-information/159336-contradictions-seriously-wtf-2.html#post1892006)
I know - you're a bunch of stoners, I should not expect much in the way of comprehension, right?


I'm finding the rants entertaining, BTW.


wow. awesome post man, i enjoyed reading it and learned a few things.

jkalb42
03-07-2009, 10:44 PM
wow. awesome post man, i enjoyed reading it and learned a few things.

stinky isnt a man lol

denialisback
03-07-2009, 11:06 PM
stinky isnt a man lol

thats true but if she was she'd be a mate anyways! :Dhehehe


Peace,
denial