To Cooltube or to not cooltube

Landragon

Well-Known Member
I went with the 400 cause i have about 5 sq ft of tent to grow in. That is still over 80w per sq ft. As long as I keep the light close I should be able to get close to a gram per watt from my 18 plant sog.

600 is my next step though. Will have to move first. :)
FYI, CO2 will be a limiting factor and make that much light a waste, without supplementation or plentiful ventilation sources from outside the house (or you leave windows open), if your grow is 5 sq ft (2'x2.5'). If it is that small, asking 80 dry grams per square foot is probably a pipe dream. But again, and sincerely, good luck, and put up a journal on that grow.
 

doogleef

Well-Known Member
Hi Dragon,

Thanks for the comments. A gram per watt is probably a pipe dream but a fun one anyway :mrgreen:. I am only growing personal so 1/2 that would probably do. I looking in to the PL stuff and it is pricey. I saw a setup on craigslist last month when I was broke:-?.

It sounds like you know your stuff and are a fan of experimentation and scientif method which is a big bonus in this game:hump:. See you around man.

Check out my grow. Just gathering supplies at the moment but we all gotta start somewhere!:mrgreen::mrgreen:
 

Landragon

Well-Known Member
it is somewhere in my notes, but what I do remember was the difference in hotspots. The internal one lit the hell out of the four closest sensors and was respectable at the sides, but was weak at the ends and corners. The external reflector was barely dimmer up close, but much more even, and imo, put out more useable light. I've seen lots of pics of cooltube grows with the internal reflector, and many seem uneven in growth throughout the canopy. Are you using a dr60 tent? A 400 is major overkill in that space. Look into ceramic mh bulbs, as they throw way less radiant heat. They also produce squat, dense plants. I have nor used one on a grow yet, but have one and have played with it. I think these two factors make them ideal as small tent bulbs. I talked my girlfriend into a new grow space foe Xmas. I used the " honey you could get your closet back, plus we'd have a place for the vaccum." argument. I know her too well. :) I get to build a space out of drywall, properly insulated and professionaly wired. Two 4x4 spaces for flowering, a 3x3 test flower, a seperate 5x6 veg space, and a mini split a/c. :) :) And an arangement at my grow shop allows that I will know in a year the hyperbole behind much of the grow equipments claims. Ceramic mh, uvb supplementation, & extended dark periods at the end of flower are the first myths to slay. I get to be the mad scientist my momma always feared I'd become.
 

doogleef

Well-Known Member
That sounds like so much fun! I would love to create a space custom for my garden. My tent is 36x20x62 so a 400W (55k lumens) will give me almost 10,000 lumens per sq ft. Maybe a little overkill but better to be over than under. That is the primary reason I went with a cooltube so I can et rid of the heat issue and set the light a few inches of tops. Should make some tight nugs:hump:
 

Landragon

Well-Known Member
Sounds good just make sure to acclimate the plants to being so close. Too intense of artificial light can cause stress and odd things to occur.
 

7th1der

Well-Known Member
Cooltubes and their ilk suck. It's on of the worst designs ever. As stated, re internal reflector is a joke, but putting on an external reflector is only marginally better. In order for much of the light to reach your garden, it must pass through the bulbs glass, the cool tubes glass , off the reflector, back down through cooltube glass, and past the bulb through the cooltube again. Pretty cappy since that glass takes 10-20% each time, as well as slightly altering spectrum unless your cooltube happens to be made of tempered low lead glass, which it isn't. Cooltubes do one thing good, cool, everything else about them is subpar. There are much better ducted reflectors on the market. I know it's too late for this grow, by next time factor in geometry and physics into your purchase. Lots of people will tout how awesome cooltubes are, but science trumps anecdote anyday.
And I appreciate the post. +rep! You mind taking a look at my cab and telling me whats best for my situation? I have the cool tube thing in mind but I always wonder'd how much is actually being lost because it would be just to good to be true to be a "cool light" kicking out that much energy? My cab is in a closet and QUIET, COOL & ODORLESS are my priorities. I was thinking about doing a cooltube/carbon scrubber combo. Only, problem is that like a fews bux and wasted hours later... am I gonna regret that shit? lol

Thanks in advance!
 

Willy Nilly

Active Member
Pull the air through, do not push... pulling is more efficient. Go with a cool tube, it controls temp better, and will probably make it cheaper than running the AC while improving plant yield.
 

GypsyBush

Well-Known Member
Pull the air through, do not push... pulling is more efficient. Go with a cool tube, it controls temp better, and will probably make it cheaper than running the AC while improving plant yield.
I disagree...

Pushing cool air is better than sucking hot air....

Putting your cooltube fan BEFORE the light.... will allow it to work with cooler air...

Cooler air is denser, allowing the fan to move more air...

Cooler air is also beneficial to your fan's longevity... running hot air over your electric motor will cause premature failure...
 

Picasso345

Well-Known Member
I disagree...

Pushing cool air is better than sucking hot air....

Putting your cooltube fan BEFORE the light.... will allow it to work with cooler air...

Cooler air is denser, allowing the fan to move more air...

Cooler air is also beneficial to your fan's longevity... running hot air over your electric motor will cause premature failure...
Lol, have you ever actually calculated the difference in the density of air between 70º F degrees and 90º F? Have a go at that tell us how many cfm that translates to. And have you ever confirmed with a fan manufacturer that warm air will cause their fans to fail prematurely or are you just guessing?
 

GypsyBush

Well-Known Member
Lol, have you ever actually calculated the difference in the density of air between 70º F degrees and 90º F? Have a go at that tell us how many cfm that translates to.
No I have not... and I don't really want to know what the difference is...

The fact that there is a difference, is enough for me...:o

Why would anyone choose the less effective way???

Even if by a small margin, more efficient is more efficient... and that is the direction I want my op to go... more efficient....:weed:

And have you ever confirmed with a fan manufacturer that warm air will cause their fans to fail prematurely or are you just guessing?
I take it you have not been around a lot of equipment in your life (I could be wrong)...

Electric motors, or any motor for that matter, will fail prematurely if allowed to overheat all the time....

All else being equal, a motor that runs hot will not last as long as one that runs cool...

Hey man... it's all good... you can put your fan anywhere you like....:clap:

But when someone comes here and says it is more efficient... I call it BS...:spew:

Cheers...
 

7th1der

Well-Known Member
No I have not... and I don't really want to know what the difference is...

The fact that there is a difference, is enough for me...:o

Why would anyone choose the less effective way???

Even if by a small margin, more efficient is more efficient... and that is the direction I want my op to go... more efficient....:weed:



I take it you have not been around a lot of equipment in your life (I could be wrong)...

Electric motors, or any motor for that matter, will fail prematurely if allowed to overheat all the time....

All else being equal, a motor that runs hot will not last as long as one that runs cool...

Hey man... it's all good... you can put your fan anywhere you like....:clap:

But when someone comes here and says it is more efficient... I call it BS...:spew:

Cheers...
I'm thought about making a cool tube/air scrubber combo. In your opinion would it be smarter to put the fan inside the cab or outside the cab?
 

GypsyBush

Well-Known Member
I'm thought about making a cool tube/air scrubber combo. In your opinion would it be smarter to put the fan inside the cab or outside the cab?
It all depends on your growspace...

I mount my fans where they run cool not hot... so if inside of the cab is directly above the light, I would put it outside...

and....

I would stay away from the combo cooltube/exhaust fan....

Keep the cooltube on it's own... with a dedicated fan and no exchange of air with the tent....

You do not want the cooltube fan to go off when your exhaust goes off...

Keep the fans separate and hook up your exhaust fan to a thermostat....

Here is a very good drawing by Al B. Fuct...

 

Landragon

Well-Known Member
Even if by a small margin, more efficient is more efficient... and that is the direction I want my op to go... more efficient....:weed:



I take it you have not been around a lot of equipment in your life (I could be wrong)...

Electric motors, or any motor for that matter, will fail prematurely if allowed to overheat all the time....

All else being equal, a motor that runs hot will not last as long as one that runs cool...

...
I'll take this edit of your post one point at a time. If you were concerned with maximizing efficiency, you would not use cooltubes, especialy homemade from glass designed to bake bread not pass light. The physics and geometry involved show cooltubes to be inefficient, and my own tests using an Apogee Quantum meter, show the glass to bock the most light in the red and blue spectrums. Sorry.

All I my fans are rated for a max air temp of 140-160•F. And I have yet to measure temps hotter than 120•F within the duct at the intake of the fan. Therefore heat moving through the fan should be no issue to it's performance. This of course assumes you aren't daisy chaining multiple 1000w bulbs from one intake and you use appropriate cfm's moving through.

We aren't running our motors hot. On all my fans, the motor is centraly located and gets air moving over it constantly.

Furthermore, if you reseached that guys posts, you wouldn't be accusing Picaso of ignorance.


And lastly, all fans I own are designed to push or pull air. However, the turbine impellers work best pulling. I have tested this myself but you don't have to believe me.
 

GypsyBush

Well-Known Member
I'll take this edit of your post one point at a time.
Right on man... I appreciate you taking the time...:-P

If you were concerned with maximizing efficiency, you would not use cooltubes,
Well, in my situation, it works pretty damn good... there is no way I could be running a 600 HPS inside of my tent without air cooling... and as it happens, the cool tube fits the tent much better than my other reflector...

It is small enough to allow the ducting to bend and give me height adjustment...

especialy homemade from glass designed to bake bread not pass light.
I do have a cooltube from HTG... and plan on using a batwing...

The physics and geometry involved show cooltubes to be inefficient,
Could you elaborate?

and my own tests using an Apogee Quantum meter, show the glass to bock the most light in the red and blue spectrums.
I agree that there is a loss of light... but heat is an issue... and I would have to say I am not lacking in the light department, I think... 600 watts in 5 sq. ft.

Please, do not apologize...

I am dumb ass that comes here to learn...

It is just common sense to me that hot air is less dense than cool air and that if you blow hot air on your electric motor, it will not last as long as one that has cool air over it...

Regardless of application... grow room... front end loader... or whatever... an electric motor is an electric motor...

But I am sorry if I came off as a know it all, I am not.. in fact I am so dumb, I have yet to pull in a decent harvest...

But I do have a little bit of common sense... I think...:eyesmoke:

All I my fans are rated for a max air temp of 140-160•F. And I have yet to measure temps hotter than 120•F within the duct at the intake of the fan.
Sure... but the closer to the edge of the envelope you get... the closer you are to a premature failure...

You can run a motor at red line (temp wise) .. but I have a sneaky suspicion that if you cool it, it will last longer...

Therefore heat moving through the fan should be no issue to it's performance.
Ok... what can I say...?

This of course assumes you aren't daisy chaining multiple 1000w bulbs from one intake and you use appropriate cfm's moving through.
I am not now, but plan on... and I do have way overkill light and ventilation for the tent because of that...

We aren't running our motors hot. On all my fans, the motor is centraly located and gets air moving over it constantly.
Sure, and if you blow hot air over it...

Furthermore, if you reseached that guys posts, you wouldn't be accusing Picaso of ignorance.
I even said I could be wrong... I did not mean to insult anyone...my sincere apologies...

But I have been around equipment all my life, and your practices in daily operation have a great deal to do with longevity and performance of your equipment... any equipment...


And lastly, all fans I own are designed to push or pull air. However, the turbine impellers work best pulling.
Hot air is less dense than cold air...

I have tested this myself but you don't have to believe me.
Hey dude, I am not a troll.. I am not here to stir anything up...

I am a newb and I am here to learn...

But just because I only moved indoors last week... doesn't mean I don't know anything about anything....

I hope I am not pissing anyone off... That is the last thing I want to do... most of you have way more grwoing experience than I do.. so I come here for help, not to insult anyone...

Cheers...

Gypsy...:joint::peace:
 

Landragon

Well-Known Member
Kudos for not feeling beat up and responding to my post with eloquence and candor.

As for elaboration, the internal reflector offers very poor spread and near useless angles unless being used in the most constricted spaces, as you seem to be doing. They cool amazingly, such is why you get away with a 600 in there. The external batwing is worlds better than the internal sleeve, but still poses problems. Much of the light must pass through glass, hit metal bounce back through glass, gets partialy blocked by the arc-tube andthen passes through glass again. This cuts overall light quite a bit, and uv-b completely in the zones most effected. It's tough to wrap ones head around my verbal diagram I know. In my tests, the bakearound blocked 30% more red than the true hydro tubes and 12% more blue.

By all means, the cooltube has it's place. I think it holds great promise for small vertical applications.

I spoke with the engineers at Soler & Palau fans about the temp range I intended to run through their fans. Their stand was the max of 140•F was to insure the permanently lubricated bearing was not damaged. They said it would take a while at 140•F to damage anything, more like around 180•F for sustained periods. Their response about 120•F was to chuckle. I figured that was all I needed.

Cool air is more dense,and therefore gives more "bite" to the impeller. But this is negligble in the range we deal with. My 400 raise the air from 73•F to 88•F. When I also ducted my exhaust fan over to my veg side as well which uses 365 watts, the temp goes to 95•F. We aren't dealng with simar situation to "high and dry" for helicopters.

I tested using a crude but reasonably effective method to determine my fans pull better. I got a big card board box. I cut 100 2" holes all over it. I then cut visqueen to size of each panel. Next I taped all visqueen panels to form a "box bag". I inserted boxbag into big box, mounted a 6" flange and got super high. Then my girlfrien came home saw my contraption in the living room and just went in the bedroom shaking her head. Finaly I hooked a sixteen foot length of insulated Thermoflo brand duct to each side of the fan. The box went in the kitchen and my fanaconda stretched across my home. First the push, then the pull. The fan was turned on and the duct fitted over the flange. Stopwatch engaged right then by other half, and turned off when bag filled box. Similar test to deflate. Deflation was 15% quicker.
 

7th1der

Well-Known Member
It all depends on your growspace...

I mount my fans where they run cool not hot... so if inside of the cab is directly above the light, I would put it outside...

and....

I would stay away from the combo cooltube/exhaust fan....

Keep the cooltube on it's own... with a dedicated fan and no exchange of air with the tent....

You do not want the cooltube fan to go off when your exhaust goes off...

Keep the fans separate and hook up your exhaust fan to a thermostat....

Here is a very good drawing by Al B. Fuct...

I got a copy of that! I was trynna kill 2 birds with one 6" Soler & Palau fan. But If I just get a 4" fan, you think I can use one of these 70 CFM PC Fan's to exhaust into the carbon filter?
 
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