4x4 Tent COB Frame Size

Hi all,

Putting together a 12 COB light frame for my first grow in a 4x4 tent. Looking for recommendations on the axis lengths of the frame. I am sure this is discussed somewhere, but for some reason I am not finding it.
40x40?
38x38?

Should the lights be more toward the outside or more in the center of each area they are supposed to illuminate?

Thanks

if its going in a genuine grow tent with reflective walls and its 4x4 you got 12 cobs their spacing is recommended at 12 inches
thats going to be 4 across and a total length of 40-41 inches depending on heatsink radious. and 3 deep at a length of 31-32

420Barista said:

if its going in a genuine grow tent with reflective walls and its 4x4 you got 12 cobs their spacing is recommended at 12 inches
thats going to be 4 across and a total length of 40-41 inches depending on heatsink radious. and 3 deep at a length of 31-32

Click to expand...

I wasn't getting any responses so moved forward with the build. Bought the lights from Timber and was trying to replicate their framework for the same size just using a little bit less material. COBs are spaced about 12 inches apart on each section, but 16 inches between the 3 rows. Do I need to fix that?

Thanks

for a 4x4 sounds perfect

Thanks Barista!

I would think approx 3x3 frame with 12" on centre spacing one way and 18" the other would give the best coverage. No need to have 42" bars unless you had say a 5x5 tent.
3' bars would give 6" spacing on either side which is about ideal IMO.

I can move the lights in on each section, so the spacing is closer between the groups of 4, but the 16" inches between the 3 sets is fixed unless I tear it apart.

This is from Timber Grow Lights, it's supposed to be 300w, will this do good in a 4x4 orca tent? And if so, what temp should i choose, 3500k, 5000k, 6500k???

Tuanis said:

View attachment 3939252
This is from Timber Grow Lights, it's supposed to be 300w, will this do good in a 4x4 orca tent? And if so, what temp should i choose, 3500k, 5000k, 6500k???

Click to expand...

When it comes to light, you get out of it what you put into it. In my case, I have three 200 watt kits, pulling close to 650 watts at the wall. This was the recommended amount of light per Dan @ Timber in a 4X4, maybe a little overkill being that it's supposed to be 1000w equivalent. I am not sure a 300 watts would be good for more than veg. Light temp depends on what you want to do, 3500 would be good for veg and flower.

Tuanis said:

View attachment 3939252
This is from Timber Grow Lights, it's supposed to be 300w, will this do good in a 4x4 orca tent? And if so, what temp should i choose, 3500k, 5000k, 6500k???

Click to expand...

No. It won't.
Traditional lighting standards say 600w HID for veg and 1000w HPS for flower in 4x4 tent. After you take LED efficiency and directed photons into account you can get away with less that those wattages for your lights, but not that much.
Orca is nice stuff, but the reflectivity of the walls won't give you much relief from producing the micro moles you need for a great grow.
Timber makes a nice product, but there are more cost effective ways for you to light your tent if you're willing to do some work. I would suggest building a 12 or 13 COB fixture using 1400ma dimmable drivers with passive cooling in a 3x3 frame. I recommend the 1400B drivers since they are the lowest amperage that can be dimmed to off.
For 12 COBs go with 3 rows of 4 COBS evenly spaced.
For 13 COBS go with 3 2 3 2 3
Cree CXB 3590s have been the go to COB for a while but technology has moved on. If you're up for the challenge, look at the Luminus CMX22 at cobkits.com They do a great job at 50w and are less than half the cost of the Cree chips. With 133mm pin heat sinks you'll never have a heat problem.
If you're up for the challenge, here's a search link to start with featuring Growmau5 posts and videos https://www.google.com/search?q=growmau5+led&ie=utf-8&oe=utf-8
Just so you know I've put my money where my mouth is here's my 16 COB fixture in a 5x5

Nice setup! I will definitely be checking those out. I am using Citizens on my setup.

Citizens are good too ... I just think in their current generations the Luminus chips have a slight advantage. And for perspective, those are 7 gal pots
I have the drivers and other electronics mounted outside the tent

I'm in 5 and regret it. I'll be moving my drivers outside for the next run. What temps you running?

77F at the top of the tent @ 55% humidity I haven't bought an IR gun to measure the canopy but I'm guessing about 80-82F when 12" from the lights. I know I can put my hand on the heat sinks and while I wouldn't want to use them as a hand rest they're perfectly safe to touch.

I have read that temps should be higher for LED, plus I have an Exhale bag which also calls for increased temps. Been trying to keep mine in the 80-86 range during the day. Agree on the heat sink temps, good way to put it.

No. It won't.
Traditional lighting standards say 600w HID for veg and 1000w HPS for flower in 4x4 tent. After you take LED efficiency and directed photons into account you can get away with less that those wattages for your lights, but not that much.
Orca is nice stuff, but the reflectivity of the walls won't give you much relief from producing the micro moles you need for a great grow.
Timber makes a nice product, but there are more cost effective ways for you to light your tent if you're willing to do some work. I would suggest building a 12 or 13 COB fixture using 1400ma dimmable drivers with passive cooling in a 3x3 frame. I recommend the 1400B drivers since they are the lowest amperage that can be dimmed to off.
For 12 COBs go with 3 rows of 4 COBS evenly spaced.
For 13 COBS go with 3 2 3 2 3
Cree CXB 3590s have been the go to COB for a while but technology has moved on. If you're up for the challenge, look at the Luminus CMX22 at cobkits. They do a great job at 50w and are less than half the cost of the Cree chips. With 133mm pin heat sinks you'll never have a heat problem.
If you're up for the challenge, here's a search link to start with featuring Growmau5 posts and videos
Just so you know I've put my money where my mouth is here's my 16 COB fixture in a 5x5

Hey man thanks for your kind words. My problem right now is, i gotta make it work like this because of budget but maybe later i will upgrade and do the whole 12 cobs, for now this will have to do. I wish i could make it bigger and slicker but yeah man, money is a problem right now...

Assuming you're going to pay $569 for a 300w Timber, think about a 9 bulb Luminus fixture for about the same money you could expand inexpensively in the future.

nunoob said:

I have read that temps should be higher for LED, plus I have an Exhale bag which also calls for increased temps. Been trying to keep mine in the 80-86 range during the day. Agree on the heat sink temps, good way to put it.

Click to expand...

Unless you're in a sealed environment, CO2 won't do you any good unless you provide enough light to exceed your plant's photosynthesis capabilities without more CO2 to process. I would be shocked if you're even close to that photon level. Of course if you just want the mushrooms, that's another story.

Some of the "bag" CO2 options come with spores to grow mushrooms once they stop generating the gas.

nunoob said:

When it comes to light, you get out of it what you put into it. In my case, I have three 200 watt kits, pulling close to 650 watts at the wall. This was the recommended amount of light per Dan @ Timber in a 4X4, maybe a little overkill being that it's supposed to be 1000w equivalent. I am not sure a 300 watts would be good for more than veg. Light temp depends on what you want to do, 3500 would be good for veg and flower.

Click to expand...

Thanks!