Introducing CobKits.com - specializing in DIY and Citizen COBs

PhotonFUD

Well-Known Member
sure if holder and heatsink costs for one chip are the same as 2 in your setup
Using an aluminum bar as heat sink/frame capable of handling 4, 6, 8... emitters. If the aluminum bar cost the same as two heat sinks and a number of holders then it would likely make sense to pass on the 2 1818s and go with the 4 1212s and even more sense for 3 or more 1818s. Plus there is still more room on the aluminum bar for expansion and you could get better coverage provided by more light sources.

This assumes that there is no cost difference for the same performance from the required drivers. And don't mind an extra bit of labor.

Will you be adding anything red region focused to your line up in the foreseeable future? Wanted: many of 620-650nm, more of 635-700nm, most of 680-700nm.

Can also be run with some 2700k providing some lighting effects appropriately, and hopefully in time, for halloween. If not, they would also work for winter holiday season. Feel free to use the aforementioned as justification to purchase the chips.
 

CobKits

Well-Known Member
does the Ideal 50-2100AN reflector
have the same size holes as the 1212 cob? description says "Can be used with or without 50-2300CR holder"?
it clears the chip, here it is on a light engine without the holder. see the two screws underneath the adapter? thats the two corner screws on the chip itself (soldered in this case)

upload_2016-9-7_21-18-1.png

even with an ideal holder it doesnt attach to the holder. just like the crees it mounts to whatever is underneath the holder right thru the open slots on the holder
 
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PhotonFUD

Well-Known Member
been trying to get some of
@welight 's linear pcbs for a while now i think hes travelling
The strips, yeah, have been watching those and the samsung ones. Both are very useful for getting light in tight spaces and the thermal impacts are very manageable.

I have also seen rectangle cobs. Eventually we will have LES on film surfaces and can roll it out like reflective material. Can't wait till those discussions come up.

CoBs are great for cutting down on labor. It is far easier to work with a few 50w CoBs than 30-50 3w emitters to get the same radiant power. (edit) or predone strips like you point out.
 

weed-whacker

Well-Known Member
it clears the chip, here it is on a light engine without the holder. see the two screws underneath the adapter? thats the two corner screws on the chip itself (soldered in this case)

View attachment 3775684

even with an ideal holder it doesnt attach to the holder. just like the crees it mounts to whatever is underneath the holder right thru the open slots on the holder

hey thats awesome! i don't need optics for my cab so was gonna solder and bare-back them to the he stink but i was going to build a high CRI lamp for my fresh water tank so might just grab 2 extra citizens and save a few bucks by skipping holders for that too.

is there any precautions i should take when running cobs in parallel? like is it nessisary to use a driver with adjustable voltage to limit the thermal runaway? (u have the 184-H 48 listed)


and also any chance you have a B version 200w driver to get rid of?
 
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Really liking these less expensive Citizen cobs. I've just been reading, watching and waiting up to this point. 0 experience with cobs.

Leaning toward the 1212's @ 20~40 watts each. Probably <30 watts ea most of the time. I'm undecided on CRI and temp/spectrum. I was thinking mixed spectrum with 3-3500k and 6500k at a 60/40 ratio. I'm estimating fixture height at about 18" or less. Going to veg and flower under the same light.
If wired in series I would be adding 36v with each cob so 4 would need about 144v, 5 would need about 180v, etc?
Probably going with the HUSA single bar extrusion. Either the 4.9" or the 5.886". Either 2' or 2'-6" long depending on # of cobs. I will probably build a shroud with a hole in the center to accept a 4" duct.

My Hortilux blue 6500k MH pretty much set the bar when it comes to veg as far as plant response goes (Tightest nodes, fastest growth). I'm just not experienced with the newer DE's, CMH, LED's etc. Then again I was vegging at about ~80 Watts per sq ft in DWC with them and I doubt most people do that.
I was thinking the Citizen 6500K for veg would land somewhere between 6500k t5's and 6500k Horti blue, obviously better than t5's. Can it match or exceed the MH?

I know Cob efficiency and lifespan greatly exceed that of the Hortilux blue, but that spectrum is just, dam I dono but it really kicks ass for vegging.

What combination of cobs would you guys use if you were trying to match this spectrum for veg? I've seen flower results here on RIU with the 3-3500k cobs and they seem fine even for full grows.
 
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Freddie Millergogo

Well-Known Member
it clears the chip, here it is on a light engine without the holder. see the two screws underneath the adapter? thats the two corner screws on the chip itself (soldered in this case)

View attachment 3775684

even with an ideal holder it doesnt attach to the holder. just like the crees it mounts to whatever is underneath the holder right thru the open slots on the holder
Can you guys add list of exactly what to buy for one of your kits on the web site?
 

emepher

Well-Known Member
How do I remove something from my cart? I'm definitely not stoned and still can't figure out how to edit my cart on cobkits.com after mistakenly adding too many of an item. I guess I could clear my cookies, but I only thought of that just now and surely there's an easier way to change your mind. I see no delete button or method for adjusting quantities.

EDIT: I can wait though, and I've found your eBay store anyway, so no big deal.
 
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JorgeGonzales

Well-Known Member
How do I remove something from my cart? I'm definitely not stoned and still can't figure out how to edit my cart on cobkits.com after mistakenly adding too many of an item. I guess I could clear my cookies, but I only thought of that just now and surely there's an easier way to change your mind. I see no delete button or method for adjusting quantities.
Does your shizzle not look like this?

image.jpg
 

CobKits

Well-Known Member
you can also type a new number( including zero) for any product (or use the up/down arrows) and then select "update cart"
 

emepher

Well-Known Member
Thanks guys, but I swear, I see no up/down arrows, no red X's, and no way to "update cart." Maybe it's just me, and I'll try my tablet, but there is literally no way for me to change quantities in my cart right now.
 

emepher

Well-Known Member
Does your shizzle not look like this?

View attachment 3776512
My shizzle looked mostly like that but was missing some shizzle, even after reloads. But my shizzle is currently correct.

Must be some weird DB glitch, I guess. Anyway, the CLU048-1818 is intriguing, as well as the CLU058-1825, of course. I can't wait to try these new Citizen chips.
 
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emepher

Well-Known Member
shizzle glitch''z :hump:
Fo shizzle da glitchelz, but cobkits.com has some great gear at fantastic prices. I was actually just pricing stuff rather than being in a rush to buy, but I'll definitely be going back there soon. Having appropriate holders, heatsinks, and drivers readily available is very conducive to successful DIY projects.
 
Can you guys add list of exactly what to buy for one of your kits on the web site?
I wouldn't say that it's a bad idea to list some basic kits if they could do it without risking any liability. No ones really inspecting our assembly for example.


If anyone's doing a mixed spectrum with these which 2 did you use? Looking at the 1212 80 cri spectrum chart, 4k and 3k looks like a good mix. It's too bad they all go so low at around ~480. Not saying that's bad just comparing to hortilux blue par because that' all I have experience with. Such a high price for that spectrum though because the bulbs don't last long, are expensive and make a lot of heat. :wall:
 
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