COB LED DIY Build Journal
- Thread starter PDX Joe
- Start date
VegasWinner
Well-Known Member
For my 3x3 I used 8 cxb 3590's with 2-185H-C1400B drivers for 400 watts. I like lower amps for lower watts and a ppfd of about 900
PDX Joe
Well-Known Member
I'm thinking I'll probably add a couple more COBs and drive everything softer when I get a chance. I'll get the fixture up into the 900ppfd range.
VegasWinner
Well-Known Member
for your door seal look for an exterior door seal kit and install similar as your tape. A soft gasket seal will do wonders. Place a guard on the inside of one of the door leafs and that will seal the inside from the outside easily and hide the seal too.
PDX Joe
Well-Known Member
I upgraded my light this weekend. I added two Vero 29 SE 3000k run at 1400 mA. The light now pulls 440 watts at the wall with the potentiometers at 100%. I'm getting everything ready for my winter grow. This will get me to 50 watts per square foot max... well over my goal of 40 watts per square foot.
Humanrob
Well-Known Member
Very nice. Are all of your heatsinks passive, or just the new ones (I don't recognize the other four sinks)? I originally built my lights with fans, but over time moved them all over to passive. I still keep a fan blowing at the light level of the tent though, to keep the air moving over the heat sinks - they can get hot.
What kelvin are the other 4 cobs? Are you using this light for veg and flower?
PDX Joe
Well-Known Member
The four Cree are on Arctic CPU fan cooled heat sinks. These four fans keep the air churning inside the light enclosure, so I think they will help a bit with cooling the passive heatsinks. The Cree are 3500k. I use the light for veg and flower. I added the 3000k for a bit more kick in flower and a bit more to the red side then the 3500k.
Tim Fox
Well-Known Member
Way cool that's exactly where i want to take my light setup , i have all the parts , but i need one more driver to have full dimming , i really like the idea. , Looks great pdx
Humanrob
Well-Known Member
I've looked at the charts and they vary a bit between brands, but I've found that 4000k seems to have the best spread if I am going with one light start to finish. I have grown with just the 4's, and it went very well. Truth is, it seems like you can grow good weed from lots of parts of the spectrum, I've known and read about people (some making their living from it) who grow with HPS start to finish. I find the different choices we make interesting, there are lots of ways to go about this. The one benefit of 4's through veg is less stretch, which is nice when vertical space is limited. My current blend is 4000 mixed with 3500, although I have one set up that is 5000k and 3000k. I've never done a side by side light comparison with the same strains, because I have been switching strains up every run. Now I'm starting to breed, so it's possible I'll have the same plants under different lights in the next few runs... but the reality is that in real time that will occur over the course of years. This hobby is not digital photography... it takes time.
Humanrob
Well-Known Member
sorry about the double post, seems to be a ghost in the machine
DrBlaze
Well-Known Member
I hope it works out well, but I think its going to run pretty hot. It looks like a lot of hot air will be trapped inside the case. It'll eventually spill out, but I bet everything will be 10-15 degrees c warmer than it would be in open air. The pin fin sinks will only be cooling from the sides, so the center pins will prob get very hot over time.
PDX Joe
Well-Known Member
The heat sink fans pushed air out the sides of the case really well on the last grow and temps stayed pretty low in the case. So, I'm hoping the fans take care of the additional heat. There is a 1 inch gap between the heatsink pins and the case (hard to see in the photos), so there should be some air circulation above the heatsink. But I may add another computer fan if it heat up too much.
Humanrob
Well-Known Member
@PDX Joe -- I'm looking forward to updates. I'm on my third grow in my 3x3. The first I used a 600w HID light with a pair of 120w Optic (4000k) COB lights, and in the end it was too much light. The next run I did with just 4 Citi 1818's running at a total of about 320w (or about 35.5w/sf), and that run was with SIPs. My plants were really thin branched, and I don't know if it was the strains, the SIPs, or if the plants were stretching because I could have used more light. At any rate, it will be fun to see how your girls do over time. There are so many variables between grows and techniques that comparisons are difficult, but all the data is interesting.
Humanrob
Well-Known Member
How's the grow going?
I can't believe that in my detached garage, I'm STILL running the AC during the day! I did not expect that, I guess the insulating I did is working and COB lights and a dehumidifier running at night makes more heat than I realized.
Looking forward updates
PDX Joe
Well-Known Member
What did you use for insulation? Did you go with rigid foam or did you use some type of batt insulation? It's good you created such and efficient building envelope. Even though my closet is indoors, I lined the inside of the walls with 2" of rigid insulation. I find it helps keep a more consistent climate in the room.How's the grow going?
I can't believe that in my detached garage, I'm STILL running the AC during the day! I did not expect that, I guess the insulating I did is working and COB lights and a dehumidifier running at night makes more heat than I realized.
Looking forward updates
I did a quick test climate check with my light in the closet to see what my new temps would be with a 445 watt fixture. The closet gets up to 82 - 85 F with my exhaust fan on high and my outside room temps at 70F. I replaced my house furnace and it has warmed up my basement to 70F, which is awesome for my finished basement, but effects my grow closet a bit. I would like to dissipate the heat coming off my light a bit so I don't have to run my exhaust fan on high all the time. That way I can keep humidity in the closet and save some energy by not running the fan constantly and exhausting valuable warm air. So, I am going to add a couple computer case fans to my light to blow air across the pin heatsinks of the two new COBs. I think that might reduce heat build up in the closet and reduce the amount of time I need to run my exhaust fan. My goal is to make the mods after Thanksgiving and then get growing right after that.
I'm also on the fence about how many plants to grow this time around. I've thought about maybe growing four and not doing a SCROG or I might stick with two plants and run it the same as the last grow in order to see the difference in results between the 250 watt light and the 445 watt upgrade. If I do the SCROG again I think I will keep the screen at least 12" from the top of the pots and maybe more. I didn't have enough room below the screen the last grow to be able to really clean up and prune the plants. I need to get rid of all the lower crap and reduce the number of colas and laying on the ground to do that sort of sucked.
Tim Fox
Well-Known Member
Looks like we are all pushing up the cob power , I am deep in rebuilding my cob panel going from 250 Watts up to 375 Watts in my 2x3 cab