Building a cob light!

What is a cob you say? Cob stands for chip on board. They have several rows of individual leds on a ceramic board with a negative and a postive. You attach these to a heatsink and then to a driver and voila, light.

im gonna be building a 6 cree cxb 3070 light ran @1050ma (2015 tek😉) l i will be taking as many pictures as i can and get into as much detail as possible for you guys! Then later ill be adding 2 more 3070s to the build to show you guys how to replace drivers and add onto your light!

Well. Lets get started!
First off i have my heatsinks. Im doing passive cooling using 105mm black pin heatsinks from HLG.

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Picking the pieces is the hard part. What spectrum(s) did you go with? Going to use holders, lenses or reflectors? Each individual or are you going to build a frame? I love my CXB 3590s 4@1750mA on a single 5.8 extruded heatsink with active cooling.

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Got my popcorn ready…

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Subscribed! Please post links to the parts!

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3500k because most cultivars will veg and flower great under it im using ledil angelina reflectors. And im building a frame with aluminum L angles.

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Sure thing moog. Ill edit that when i get gome and post links to every piece i bought. For chips and drivers etc go to www.findchips.com

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When spacing your heatsinks you really want everything as even as possible. I like to use a solid ruler and space everything depending on which chips youre using, how many, your space, what reflectors etc. Since these 3070s are a bit smaller then the 3590s im going to space them less then a foot apart.

with the 3590s i would do a whole foot space in between each heatsink.

Make sure to get them spaced how you want before marking your drill holes.


Remember, measure twice and cut (er well drill) once.

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Got a ticket for this show :wink:

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@lotus710, exceedingly interesting thread!
I have been on the fence regarding LEDs, for various reasons, one of which is the cost.
If you would be so kind as to break down the cost of the different components used in your build, I would be greatly appreciative.

Will the links you provide(I hope)show pricing?

Thanks much for this illuminating thread😄!

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I can always add the prices dude!:slight_smile:

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When spacing your cobs you want them about a foot apart. Give or take. So break out your drills and get drilling.

make sure to measure everything properly or youll end up with holes in wrong spots.

you wanna make sure all your predrilled holes are lined up the same. So your solderless holders look neat.

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Keep up the work, can’t wait till it’s done and all lit up! I have pictures of my COB build around somewhere if you want me to post them here I can :smile:

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You could post them over here:) id love to see it

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so for solderless connecting we use a holder by ideal. Its the 50-2234c. It using a technology called “chip-lok”. This is a little spring on the negative side of the holder that holds your cob in the holder making it easier to install thermal paste and to get it right where you want.

On the positive side there will me a little +. Line it up with the + on the cob and insert. You have to use a little force so be careful not to crack the ceramic.

Once insterted into the holder you want to apply a little bit of thermal paste. You wont need much at all. Spread it thin and as even as possible.

Now line it up with the holes on the heatsink and screw them in. PLEASE PLEASE dont use any pressure. Ideal says to only use 2.5-4.5 inch-lb. Which is basily no pressure. Screw each screw intill its almost touching the holder then do one turn on a screw then one turn on the other and repeat untill you feel the slightest tension then stop. Check the screws after the lights been running for a bit to see if they got loose from the grease spreading out.

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after you get your cobs on the heatsink were gonna use some reflector adapters from ideal. They are made for the ideal cob holders and ledil angelina reflectors. These are simple to install. Slip screw in the holes. Line the positive marks. And screw in gently. Dont do it tight because once again, ceramic chips. and then you can easily twist on the reflectorsim using ledil angelina-w f13402 reflectors. I got silver ones because the white was out of stock.

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What angle are those reflectors @lotus710? They look like 120…

Great job by the way…

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Thanks man. And its a 57

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Look at U go Brother Grower. Colour me impressed to be sure. Seriously impressed and appreciative too. I’m thinking about ordering this exact setup myself as soon as I’m able to purchase in Canada. I’m working on my latest project of 5 Candy Cane Auto Flower Femz from: Crop King, I know I know Lotus without getting into the whole horrific last 2 months of my life aka Grow. I’m happy to say that I will be sharing this Grow with Overgrow. I’m truly happy to see you are still here and sharing the COB aka the future of Grow Lighting I’m looking forward to seeing my new COB Light in action with these Autoz

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