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Sure, that can be done, as well. The C22s that I built years ago had 2x8" darkroom louvers on the side opposite the exhaust and 4 x 4" louvers running the span on the floor, mounted low on the back of the cab. Saddled with a 600HPS, the box easily maintained 1-2F above ambient and yielded 2-3oz per square foot (dry/cured).
That's the beauty of being able to configure a room to one's environment. As long as one understands the idea, the rest is downhill.
Simon
J23
Member
thanx for the tip hoosierdaddy.
I opened a new thread for my box: http://www.icmag.com/ic/showthread.php?p=3189941#post3189941
I opened a new thread for my box: http://www.icmag.com/ic/showthread.php?p=3189941#post3189941
Alright. Frustration. I know I've read it before in this thread but now the "search this thread" function isn't working and my google searches are coming up empty.
Can someone remind me what happens when you stack axial fans?
I have two Dayton 100 CFM fans that I am thinking of stacking to ventilate my cooltube (400W). I know on paper that 100 CFM alone would work, but the lantern globe I'm using is hourglass shaped and I'm a little worried about the constriction where the air passes over the bulb in the narrow part of the passage. I'd rather over-ventilate it than underventilate it, but I'm trying to figure out what CFM I might be dealing with and how the psi is affected by stacking axial fans.
Thanks and sorry I can't find it on my own. This thread is pretty big!
Dig
Can someone remind me what happens when you stack axial fans?
I have two Dayton 100 CFM fans that I am thinking of stacking to ventilate my cooltube (400W). I know on paper that 100 CFM alone would work, but the lantern globe I'm using is hourglass shaped and I'm a little worried about the constriction where the air passes over the bulb in the narrow part of the passage. I'd rather over-ventilate it than underventilate it, but I'm trying to figure out what CFM I might be dealing with and how the psi is affected by stacking axial fans.
Thanks and sorry I can't find it on my own. This thread is pretty big!
Dig
ITryToGrow
Member
Dignan: Stacked fans handle static pressure better.
One on top of the other equates as a better ability to overcome pressure. Such as pulling across a high static pressure surface such as a carbon filter.
When fans works side by side supposedly you add together the CFM rating's as long as they are ventilated SEPERATELY, otherwise its just stacking intakes.
When fans works side by side supposedly you add together the CFM rating's as long as they are ventilated SEPERATELY, otherwise its just stacking intakes.
gdbud
Member
Run a funnel around your passive intake. You wouldn't run a light without a reflector, why run your fan without the same priniciple.
Are you referring using a bell-month opening?
I have incorporated two of these in my cabinet one on the Cool tube inlet and the other on my fan inlet by using round diffusers. works great!
Are you referring using a bell-month opening?
I have incorporated two of these in my cabinet one on the Cool tube inlet and the other on my fan inlet by using round diffusers. works great!
Dignan, the bottleneck in your setup is the glass itself. The smallest diameter in the pathway is what dictates how much air can pass.
Stacking the fans, as mentioned, will increase the pressure it can overcome yet not increase the CFM. Even if you provided the two fans Y'd into the glass, it would still be at the mercy of the smallest orifice and you would not be able to increase the CFM to what the two fans could create if they were not hampered by the small bottleneck.
Stacking the fans probably won't make much more difference than a single fan, but it won't hurt anything.
If you want to increase the cooling ability of the setyup fast and easy, replace the hurricane globe with a cylinder. You can get them at any hobby lobby (and online) for cheap. They have a larger diameter than the hurricane globes do.
Stacking the fans, as mentioned, will increase the pressure it can overcome yet not increase the CFM. Even if you provided the two fans Y'd into the glass, it would still be at the mercy of the smallest orifice and you would not be able to increase the CFM to what the two fans could create if they were not hampered by the small bottleneck.
Stacking the fans probably won't make much more difference than a single fan, but it won't hurt anything.
If you want to increase the cooling ability of the setyup fast and easy, replace the hurricane globe with a cylinder. You can get them at any hobby lobby (and online) for cheap. They have a larger diameter than the hurricane globes do.
Run a funnel around your passive intake. You wouldn't run a light without a reflector, why run your fan without the same priniciple.
Are you referring using a bell-month opening?
I have incorporated two of these in my cabinet one on the Cool tube inlet and the other on my fan inlet by using round diffusers. works great!
Yes thats what i'm referring to People spend lots of money on reflectors to extract the best footprint of light for their given wattage i.e. most efficiency possible for given situation. At least in most case
So why wouldn't you do the same thing when it comes to your fans and setting up your ventilation properly. This allows you to use smaller holes vs. one's without the bell shaped.
It's not neccesarry if your running huge holes to fit your fan, but this allows some of us with limited space to get away with smaller holes. I use two 4" holes on my stealth cab for a 6" even though its only pulling about half power through a scrubber.
robbiedublu
Member
big ballen,
The diameter of your exhaust dictates the diameter of the intake no matter the orifice configuration at intake. All the shape of the intake does is allow a given amount of CFM to flow with less resistance. A 250CFM duct fan will start to feel the need to pull harder with say a plain end duct as opposed to the bell mouthed duct and the cheap fan will labor to push the 250 CFM. A better fan with a better rating at 250CFM may not realize the increase of resistance and the fan may not labor at all pushing the same 250CFM.
Although modifying the intake orifice will indeed allow a fan to work at any given CFM with less resistance, it will not change the physics that determines your intake orifice size.
If you have a 6" exhaust, you still need to have an intake at least 10% over that size.
Note in the drawing they show the same amount of arrows going in, just in a different path with different turbulence's.
The diameter of your exhaust dictates the diameter of the intake no matter the orifice configuration at intake. All the shape of the intake does is allow a given amount of CFM to flow with less resistance. A 250CFM duct fan will start to feel the need to pull harder with say a plain end duct as opposed to the bell mouthed duct and the cheap fan will labor to push the 250 CFM. A better fan with a better rating at 250CFM may not realize the increase of resistance and the fan may not labor at all pushing the same 250CFM.
Although modifying the intake orifice will indeed allow a fan to work at any given CFM with less resistance, it will not change the physics that determines your intake orifice size.
If you have a 6" exhaust, you still need to have an intake at least 10% over that size.
Note in the drawing they show the same amount of arrows going in, just in a different path with different turbulence's.
The only thing i was really trying to state was that your minizmizing your vena contacta losses by using the bell shaped vs straight. I think i was too stoned while writing, all these papers are starting to get to me, thank jah for spring break next week.
Less resistance is gonna mean you can use the same space as before more efficiently with less loss which is my main point, i probably went to far as to say it cut's down the amount of intake size drastically. Think of an individual intake runners of an engine, if you change the shape of the runner from a bell shaped to a flat wall your gonna lose some of the power since the engine can't pull the same amount of air as it was prior to the modification. This is my main reason behind the way i'm thinking.
Less resistance is gonna mean you can use the same space as before more efficiently with less loss which is my main point, i probably went to far as to say it cut's down the amount of intake size drastically. Think of an individual intake runners of an engine, if you change the shape of the runner from a bell shaped to a flat wall your gonna lose some of the power since the engine can't pull the same amount of air as it was prior to the modification. This is my main reason behind the way i'm thinking.
windsoft
Member
I think I read around here that this was supposed to be similar to a 465 dayton blower.
Do any of you know with any certainty how much heat is generated by a 400W HPS bulb?
I am trying to figure out if I can use a certain plastic for the coupling at each end of my new cooltube. Specifically, I am hoping to use two of these:
They would allow you to easily access the lamp to change bulbs and also to dust/clean the inside of your tube.
My guess is that, with a 100 CFM fan exhausting the cooltube, temps might be in the 120F range. But I'm also concerned about fire in the event of the fan failing.
If it's a hairbrained idea, I will head back to the drawing board.
I am trying to figure out if I can use a certain plastic for the coupling at each end of my new cooltube. Specifically, I am hoping to use two of these:
They would allow you to easily access the lamp to change bulbs and also to dust/clean the inside of your tube.
My guess is that, with a 100 CFM fan exhausting the cooltube, temps might be in the 120F range. But I'm also concerned about fire in the event of the fan failing.
If it's a hairbrained idea, I will head back to the drawing board.
That looks to be a clothes dryer vent, which should take a good deal of heat to begin with.
I would think it a similar thing to venting the heater coils of the dryer.
They may not be as light proof as you want though....
A tinker could always take a duct flange and bend the tabs out so he could screw it to the dryer vent flange (or the box for that matter) and use aluminum flex duct.
If you are interested, I show how I do the flanges in the Stanley Blower DIY thread. Instead of screwing it to the side of the blower, it would be the box in your instance.
I would think it a similar thing to venting the heater coils of the dryer.
They may not be as light proof as you want though....
A tinker could always take a duct flange and bend the tabs out so he could screw it to the dryer vent flange (or the box for that matter) and use aluminum flex duct.
If you are interested, I show how I do the flanges in the Stanley Blower DIY thread. Instead of screwing it to the side of the blower, it would be the box in your instance.
