new design for first grow box

[highharry]

Hi all,

here's the new idea for my first grow box.

After pricing the timber for the frame(way to expensive, it would have used up all funds), i have decided to go with a nice thick refrigerator box with a thin wooden frame inside for support. 600mm x 750mm x 2000mm. There are three reasons for this height, a) there is a AC frame at this height, so it will be attached to that for overall stability, b) I live in the tropics, so am betting that humidity and temperature will be a big issue, which i'm hoping the raised ceiling will help to control. (like it does in architecture design), and c) i have to allow for the pot height and a space at the top for the internal gear, so all told the available internal height is 1500mm.
Intake fan(100mm) on the bottom left, out-take fan(150mm) on the top right, 2 fans internal at the top and 1 at the floor.
I have calculated that it will need between 12(6,720 lumens psf)-14(7840 lumens psf) 42 watt CFLs. Is this around the correct number? too many?
They will be arranged: 7 bulbs in a horizontal frame able to be raised and the other 7 around the sides of the box vertically. I was thinking of using the longest bulbs i could find on the sides, with the frame being hung between and raised as needed.

Any suggestions greatly appreciated,

Cheers, hh

 

[The Hemp Goddess]

Highharry, pay greenough no mind. He is simply a cheap spammer that is somewhat illiterate.

I guess that my first questions is, if framing timbers would have taken all your money.....how much money do you have for this project?

I believe you can probably make the box work if you can make some way to access it, but also be able to keep it totally dark when you get to flowering.

I would rethink using CFLs at all. Twelve to 14 42W CFLs are going to create an incredible amount of heat and small axial fans will not even begin to keep things cool. In fact, keeping that many CFLs in that small a space cool may prove impossible without pumping A/C dirdctly into the box. In addition, 42W CFLs are going to take 504W and give you around 33,600 lumens. Compare this to a 400W HPS that will give you 50-55,000 lumens--about 33-40% more light for 20% fewer watts. In addition a 400W in a cool tube would make cooling things a whole lot easier. For your space, even a 250W HPS (which puts out about 28,000 lumens would work). But, IMO whatever light you get, you really need some kind of air coolable hood.

Heat and humidity are going to be your problems. An intake fan is not necessary. But a good quality centrifuge type exhaust fan is a must. And a small oscillating fan will move the air around. You may also need a dehimidifier.

 

[Hushpuppy]

I would add something here but The Goddess has it covered exactly. Trust this lady, she won't steer you wrong

 

[budz4me]

hey harry, as a newb myself I started (and am currently using) with CFL's. THG...as usual.....is correct. I am simply using them to veg while I gather funds to upgrade my setup.

Even at a meager 22k lumens, I am finding it hard to keep my 2x2x5 box below 79*F. So venting must be a priority, regardless of your light source.

Best of luck and good mojo friend!

 

[highharry]

thanks for the great suggestions,

the timber was going to cost around $100, not a large amount I'll agree, but was around 1/2 of my funds. I'd rather put more into the lights to be honest.

I have read that the minimum amount of light required is 3000 for vegging and around 5000 for flowering, if i reduced the amount of bulbs to just above that, say 4500 for veg and 6000 for flowering, would that be a reasonable reduction in heat?

I thought about putting vents on whole left side of the box, then flywire over these for the critters, then hood the whole side to block the light. Would this work? I can't put AC into this, the AC frame is just there but it doesn't unit doesn't go, however, a trick I have seen is to place a large block of ice on a tray at the bottom and run an oscillating fan over it. Works in a hot humid bedroom here, so it should cool down the box, right?

Cheers, harry

 

[buddogmutt]

It doesn't sound like you can afford to do this the "right" way..IMO you're setting yourself up for disaster...and with summer here...as stated above..heat
/humidity are going to be issues...I'd save my $$ until I can afford decent hardware..or wait til summer ends and temps to cool for this box idea at least...

 

[The Hemp Goddess]

You may find it hard to put a grow together for $200.

I don't see the ice thing working (this is basically how a swamp cooler works). In fact, it will probably add a lot of humidity to an already humid condition. But, there is more than just the heat. You are going to use about twice as much electricity to get the same lumens from CFLs that you get from HPS. In addition, the CFLs do not have the penetrating power of CFLs. How much are you spending on your CFLs--bulbs, cords, reflector, sockets? Like I mentioned earlier, I don't see those fans as being adequate for your purposes. Axial fans really do not move much air.

 

[N.E.wguy]

Htg has a ballast and hps light for like 70$ would be better then the CFL speaking from experience and THG is a 100% read my thread you will see