Non-Venting grow box - Aluminum

I was wondering if anyone here has knowledge of the heat transfer capabilities of aluminum.

Say for example, if one side of a grow box was a sheet of aluminum instead of wood - I'm thinking of avoiding exhaust fans for cooling and letting a sheet of aluminum roughly equal to 1/4 of a grow box surface act as a giant heat sink / heat exchanger helping to bring the temperature inside of the grow box in line with the temperature outside of the grow box.

Think heat sink on a computer processor.

Any thoughts on what type of aluminum would have better heat transfer properties? I know you can sheets of aluminum at any hardware store, I'm wondering of some will exchange heat better?

you would need supplemental co2 if you had no vents

Yea I know, I wasn't asking about that, I was asking if anyone knew about aluminum, or had any experience, ideas, or knew what types might suit my purpose.

I dont think the heat tranfer would be fast enough personally. Unless your room is cold as shit...

If Aluminum was a great heat sink then why do all metal cabinets need to be well ventilated for a sucessful grow?

The heat transfer from the inside of the cabinet through the aluminum skin and into the ambient air outside is nowhere near enough to cool the inside of the cabinet when dealing with any significant heat source from a light.

I doubt those metal cabinets are made of aluminum - at that thickness it would cost a fortune - and you could pick up an 8 foot cabinet with 1 hand.

It is a good heat sink, that's why if you look into your computer you can see grey things with spikes on them, on top of all the processors that get hot. It's even often used on the ballasts themselves as a heat sink.

Again, anyone with experience, I think there are different kinds of aluminum alloys, wondering what kinds to get, avoid, if anyone knows - talking about the local hardware store stuff.

Thanks

use a watercooled system man that would do it

tomatofarmer said:

I doubt those metal cabinets are made of aluminum - at that thickness it would cost a fortune - and you could pick up an 8 foot cabinet with 1 hand.

It is a good heat sink, that's why if you look into your computer you can see grey things with spikes on them, on top of all the processors that get hot. It's even often used on the ballasts themselves as a heat sink.

Again, anyone with experience, I think there are different kinds of aluminum alloys, wondering what kinds to get, avoid, if anyone knows - talking about the local hardware store stuff.

Thanks

Click to expand...

Good luck with your science experiment. Let us know what happens.

haha ok, this is crazy - first post and answers about everything I didn't ask.

And defumidiers aswell, And carbon scrubbers. We all get high dude it's ok

P@ssw0rd

ok, saying foil does not transfer heat - I seriously hope you were high when you wrote that...

the reason it's cool to the touch seconds after is that it is so good at transferring heat it cools to room temperature in seconds (and in fact will cool your food quickly).

You'r basically talking energy - hot or cold - to remove heat or add heat, it works both ways. If you have a small aluminum sheet in a room thousands of times the size of the sheet, the shift to equilimrium is seriously and greatly going to be rapid towards room temperature - hence my initial question.

If you have ever seen those miracle 'defrosters' that defrost meat in sminutes not hours, they're usually just a coated aluminum or copper slab.

Anyway, back to my question, anyone have experience or knowledge of types of aluminum you can commonly buy?

I was looking at copper sheets too, apparently it's heat trasnfer capabilities are almost double that of aluminum.

When you said people were off topic, i think they were just trying to point out that exhausting also controls humidity levels and fresh CO2. If you did this you would need to basically do everything that you would in a CGE (closed grow enviroment) enviroment minus the AC. CO2 will alos let you run slightly higher temps. I think it may work depending on your heatload. You would also need to keep the room immediate are around the cabinet cooler, wheather you do that w/fans or AC i guess would be preference. You would need goo internal circulation to have the heat inside hit the side walls.

I definitely want to see you try it. I personally just wouldnt due to the cost involved and mine would look like shit..lol. Alos i build my cab out of two 2x3x6.5
steel cabinets and decided to insulate them to eliminate my air pump, bubbler, ballast, and internal air circulation fan noises. You may not have this problem if you go dirt. I just found that the metal cabinets didnt block the high frequency noises as well as prior wood cabinets i have had in the past. Being that thinner aluminum will transfer heat and noise better I would try to eliminate all sounds in the cab. Oh...Ill sell you this plasma gun i have collecting dust that i used to make my cab...lol

Guess it just comes down to cost financially and in other enviro factors vs. you being able to run without a ari cooled hood and small dehumidifier or an exhaust fan.


copper is better at heat than aluminum, sivler better thn copper, diamond is better than silver. Depends on your funds bro. Bling Bling

Good luck

Consider this, if you have no ventilation system, and enclosed box, Your plants will WREAK of weed when they flower. You cant make it air tight, even if adding supplimental c02 the gasses have to go somewhere. There are alot of other factors then heat that detrimentaly affect growing.

Plus I hope your room NEVER reaches temps in the 80s where it will match the heat output of the t5 (HID out at this point) or your box will acually absorb heat, have you considered aluminum works both ways?

Hi, thanks for the input. I guess you're right that aluminum works both ways...but I'm guessing that it will try to reach an equlibrium, and will always try to get to a temperature in between inside and outside the box.

So if the external temperature is, say 80 degrees, and the inside of the box is 70, I imagine the box will absorb heat. Once it does get over 80 degrees inside the box however, I'm thinking that the equilibrium will force the hotter inside the box (which would be above 80 at this point) to try to get back down to the external temperature.

I'm not trying to make the whole cabinet out of aluminum but that's for the plasma gun offer - I'm going to do the back wall, which is equal to about 1/4 the surface area of the cabinet. I'm not going to put aluminum reflectors over the lights, the inside box will be white melamine paint. So I'm hoping the aluminum on the back wall will act as a reflector as well, and be the primary draw of heat off the lights, in the way that an aluminum reflector and casing is for a typical light fixture - only instead of disipating that heat back into the cabinet when it absorbs it from the lights and air temp, I'm hoping it will dissipate it to the outside room.

Odour will be a concern - I was thinking of those gel's that others have talked about inside the box. I'm also thinking of not makingn it 100% artight - but about 95% and almost totally light tight, by using a small amount of bent ducting. You're right there will need to be some gas exchange at some point. I'm sure it might work (the plant in a pop bottle science experiment comes to mind) with even opening it up daily or a few times a week, but I think some small exhaust will be necessary.

Smell control will be a challenge, I'm hoping loading up on that gel (I think it's called ona) can take care of it.

My goal is that the only thing that relies on electricity is the lights - everything else I'm hoping to control passively without electricity being required - smell, heat dissipation, even co2 (I read how to make it on here naturally) so in the event that anything electrical does stop working, the 'stealthness' of the box isn't affected.

Could be done. Worth it? not sure.

A finned heat sink wall on both sides might work.

Might need a double wall with fins inside and configured with a convection design where the hot air rising creates a flow.

Gonna need a LOT of surface area for an air-air heat exchanger.

Good luck.