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Budget COB DIY

Ifbleaf

Well-Known Member
I'm not sure if it's within the realms of the sponsors to hear about my as yet unproven take on a set of cob powered lights...
Basically I took a cheap blurple 100w cob with a plastic diffuser lense siliconed around it. You may well have been offended by the claims they make amoungst the rest of the spam type distraction from the browsing the top end Samsung/ bridgelux. So I have bought a blurple w cob lamp as described, then whilst drawn into a sales site through the amazing coincidence that they were offering exactly what I have been looking into. Suprise phishing or something like massive amounts of data and logic wired for sales. Anyway there's a offer of a cob mains power compatible little bulb/ chip board. So when I get it you could have knocked me down with a feather,,, it's only a couple of screw's and solder 2 cables and the blurple is now a 50w 3000k 120-180° beam angle. A minor issue for the light performance I am hoping to see. The original blurple lights come in single, double, & even triple chip versions and I am not sure if using the original 100w in the white colour will be too much heat unescasarrily. I'm thinking that 50w each unit is about right with the plastic diffuser lense and the wafer thin heat sink
Still thanks to advertising and' wish' marketing offering me a mains power,20/30/or50 w cob chips for less than a UK pound about a dollar at present rates. So I am sucked in to buying a remnant of the products that I was drooling over and stone me,,, it's only the best thing one could have done for the blurple watt flood light. Now sports a lovely warm white flowering shade of grow. Infact I'd say from recent additions of 100w CFL bulbs to my babies,& I cannot look at the 50w cob, it is far too intense were as I have problems with other lights whereby I end up with the light in my eyes more than I am happy for. The cob is just a simple you don't/ can't do it. Still I'm waffling like a bad journalist. Aha. I'm not sure but I've high hopes for my DIY discovery. It isn't rocket science although it is some science of electronics, and there is an element of ongoing mortal danger of electrocution and the Chinese original manufacturer of the light unit are making so many things that are potentially electronic hazards.
 

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Ifbleaf

Well-Known Member
Fkt I have been and got about 300w of the AC cobs coming for about£20 ?? All meant to be a 2800k to 3200k I'm going to get a heat sink and screw them on. Also have 50w of 12v DC festoon cob bulbs in 6000k . Going to put them in a basic barn hood reflecter and short the wiring and power supply. Series/ parallel and the best brightness.
 

Ifbleaf

Well-Known Member
Sorry about the picture quality, I've tried to show the way I am using the decent gauge steel strip, that is the backbone of the original reflector. I've cut the dimpled aluminium down the centre and folded it over to expose the steel that I hope to mount the cob chips on to. I'm stuck with how to get the right kind of diffuser lense. Infact, about 2weeks ago I was going through WISH shopping maize of the most over engineered,under quality pieces of sale items!!!!!!;;!!!!! And having ordered a few more cob chips was stunned to see the plastic diffuser lenses exactly the same as the ones that are on a choice. If they're all over the market here then it must be with you on the other side of the' pond' as it were, look.
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Ifbleaf

Well-Known Member
Also I have included the vendors pitch at the lights ability and power
Notice it's claim to be 600watt. It's either 300or 150w each cob is 100 watt AC in the famous term"FULL SPECTRUM" surprisingly this one actually admits to being a pink colour in the sale spumph. Back to the point, the lenses were £2 each. I was hesitant as I didn't know that I have the funds to cover the purchase. Can I find it again. Of course not.slightly gutted . I'm not wealthy and I know that it is easy to purchase the whole thing and change the chip as I have done with the single chip version of the light I have been so nice about. On the camera screen, the light waves are so distinct and separated by a slightly wider looking darker wave. This surely is the same as being in stripes of 50% shade and obviously 50% light,, actually it's more like 60/40 , with 60 being the shade...
Despite the chips being unbranded Chinese,and the AC lack of consistency of the light. I'm going through with the motions and hope that using a larger wattage than the intended led being cheaper to run at least provides the extra light spread I will be needing, God willing.
I have one of the single chip lights that I have replaced the blurple with 2,800k to 3,200k 50w. Cob. I've got it propped up against one end of the light AC hood with 250M/H in . I've moved my now 2 week old regular seedlings under this along with the 3feminised girls already basking in it. Joy. They all love the light ( no surprises) the 50w cob puts a distinct peachy orange shade across the whole MH lights footprint. It's hard to say that the cob source attracts the girls and the 10 regular mix of unknown strains just all indica dominant and all short flowering strains. Of course they are. I cut everything down on Day 65 regardless.:yummy::meatballs::snowboating::adore::kiss:no I don't. They never get to day 65. As yet. .
 
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Ifbleaf

Well-Known Member
2 of the cob 50w chips arrived bent in half, almost folded over ffs. I got an instant refund after sending this picture to the chinese supplies. Well I don't have a picture anymore and can't take another one as I've straightened them out . Still life goes on, I've just been surfing online and found 100w dc 3000-3200k 36v chips. I've bought 3 for£8.80!! Going on to research drivers now. Then I will be looking at combining some epistar far reds and some UV range LEDs. To make this a serious effort.
 

Ifbleaf

Well-Known Member
I've got ten 5w cob 12v festoon style for automotive industry. 6000k thinking of looking for a decent driver and wire the lights in series or parallel, probably a bit of both, so I can get a good driver and use it while I save for a quantum board.
It's a plan. I've got an order for a number of other dc cobs on PCB design but dunno if I have the soldering skills to get them on a usable layout.. the 5w 12v festoon style cobs are blinding.
 

Ifbleaf

Well-Known Member
Actually I have 4 of the 100w cob chips. They're rated at vaguely 28v/ 34v pretty much. I'm up with series and parallel, with the wiring. I'm seeing people saying wire in series for better brightness. I think this is the better dc purpose built drivers. I think I have noted the high voltage range of some of them. I'm also thinking of putting the prototype inside of a small AC reflector hood. Making sure it's kept cool (4x100w cobs on a make shift heatsink) but I've used an old open barn hood reflecter as my heatsink/reflector. I've got nothing to focus or/ and diffuse the light source. But I'm thinking they are cheap 120°\180° light angle. It's not the same as Samsung LM top bin cobs. Actually it is. Cobs on a board like the quantum board style. I'm starting to get to the vision. Cheap high power cobs with some of the 180°light getting reflected by the traditional housing I've attached them to. I can get it done by running all 4 cobs in parallel and believe that the transformer I'm going to use will be able to power them nicely.
That's all I imagine to now. The blurple single double and triple lights I've been thinking of using are off the menu totally.
So are AC chips, dunno what I was on. I've got a nice array of AC lights for work bench lights though. I've got 10x 5w12v 6000k festoon style replacement cobs & I am shure they'll straddle a steel rule as a heat sink/mount board. They are really good lighting . Just one 5w dabbed with 12v is a blinder. They are nicely made with the festoon style big shiny metal festoon style fitting , making it harder to adapt their application.. enough. If it is getting done it's going to be now or an indefinite period of time.dundadaa
 

Ifbleaf

Well-Known Member
So ironically I have gone from consideration of the AC cobs with Thier strobing issues. To replacing a 400w ballast hid kit that doesn't make full wave rectification. The 400w sodium is strobing as well. So having bought a similar amount of DC cobs, I am now looking at replacing it with the dc cob chips and gonna put them in the air cooled hood as I ain't got no big cob heat sink. Or diffuser lenses. Hopefully 300w of 30v + cob at3000k will be good. May have to keep the distance between the light and plants as it's possible that the undifused light will be too much. We can hope.
 

Ifbleaf

Well-Known Member
I was thinking about building a board and adding cobs into it. Just thought id NEVER have the time to do it. Gonna follow along to see what you come out with
Welcome. My first true observer. I hope you see what I glue together and improve on my cack handedness.
 

HugePeckerhead

Well-Known Member
Welcome. My first true observer. I hope you see what I glue together and improve on my cack handedness.
Thanks. Make sure you use duct tape. Lots of it. :laugh: last week I was looking into building mine but after looking into it I realized it's a project that I'd never get done.
 

Ifbleaf

Well-Known Member
Thanks. Make sure you use duct tape. Lots of it. :laugh: last week I was looking into building mine but after looking into it I realized it's a project that I'd never get done.
IMG_20190912_201703.jpg

This is my prototype! I'm using the steel backbone of this old reflector as a heat sink. I'm putting the other side of the reflector back on, naturally, and have been thinking a good idea may be to fix a proper heatsink on the back of the steel plate I'm mounting the cobs on. In reality, I'm going to put it in a air cooled hood for now. I thought that I would be able to run them from an old printer transformer that was 30v . It cuts out. So I have got 3 100w constant current dimmable drivers coming from China. Cheap! Hopefully I will get the bits soon as I can't wait to test it out. You may have read that one of my HID ballast is a kit that doesn't perform more than halfwave rectification. It's DC but pulsing. I noticed this on the camera screen so I am hoping that I get the drivers soon as possible.waffle. the picture is basically 3 cobs with a small nut and bolt on 2 corners ( could be all 4) going to have heat insulation on the wiring directly from the lamps. Not sure how to deal with the 3 drivers. Heatsink paste which is cheaper from a plumbing supplies than a electronics supplies will charge.
The rest is yet to see. Will the lack of a diffuser lense be an issue. I'm hoping that the 300 w blasting out of the hood Will disperse and also reflect the light in a way that delivers an even light level onto the plants.
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Ifbleaf

Well-Known Member
The reflector hood is a bit over 400mm. So I have used 100mm centres for the chips. This at least put some uniformity to my pipe dreams. Funny how it's clear in my memory. I'm thinking the cheap ,yet 100w cob, boasting a 180° light angle is far from the 90° -120° angles Samsung boast. So if we ain't got an acute light source? There's not much to diffuse. Infact I'd hazard a guess that, just as a sodium lamp has a 360°light emission the 180° cob may be a sweet spot in a largish air cooled hood???. Hopefully I will be able to run the prototype for this grow. They have been on 12/12 for 2nights maybe 3 . Oh dear. Nah I'm sure it's night 3. Or 4.
 
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