Custom COBCRETE

Fine $28 then. Can't get CXM22 from Digikey or Mouser since they don't actually seem to sell them, so the only alternative I see would be $17 plus twice or triple the shipping cost and 25% import duties from a European perspective. CXB3590 still the easier choice.

Does an 1818 really beat a CXB3590 at 61.5W and lower?

Id call em equal down to about 25W, CXB pulls ahead ever so slightly way down low

CobKits said:

1818 out performs it as does the $17 luminus cxm22

not sure where cxbs are $27
$30+international shipping at cutter
$28+paypal fees+international shipping from kingbrite
$38 domestically at rapidled

$17 vs $32-$38 is pretty significant

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The cxm22 has my attention. what about heat sinks? what about the question from another member above about being able to use constant current drivers and serial wiring? Even after watching hours of Growmau5 you tube I can't get my head around these COB fixtures and I want to be sure I choose WISELY

Can you experts compare gram/sqft between 66W/sqft HPS and 37W/sqft COBs?

waveman said:

The cxm22 has my attention.

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waveman said:

what about heat sinks?

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as for pin fins, 120mm up to 50W, 133mm up to 75W

waveman said:

what about the question from another member above about being able to use constant current drivers and serial wiring?

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there are slight advantages and disadvantages to both series and parallel wiring. any cob can use either you just need to select the proper driver

waveman said:

Can you experts compare gram/sqft between 66W/sqft HPS and 37W/sqft COBs?

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depending how hard you want to run them, id reccomend 40-45W of cobs per square foot to match 66W of HPS

anyway, i want to answer your questions but i dont want to hijack welights thread anymore than we have, prob best to start your own thread or pm/email me if you need help with anything

CobKits said:

Id call em equal down to about 25W, CXB pulls ahead ever so slightly way down low

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Ah thanks. That chart shows them rather equal over the whole range though. Crossover is around 45W?

Also, for some reason the 1812 and 1818 generally seem to come out more expensive than the 1212 and 1825 for the same amount of light at equal efficiency. Maybe I'm calculating it wrong, but I get the feeling their pricing is slightly off.

Overall, Citizen COBs just seems to go up in price while Cree prizes are coming down. So the gap is also shrinking a bit over the whole line.

Was trying to help someone find the right COBs for his room and the Citizen's just didn't really seem to save much money. At least not on the 181x models. In the end he went for 1212's (with free shipping and no paypal fees) and that did come out much cheaper. Better light distribution too of course.

Too bad the cxm22 and othe models is so hard to find over here.

waveman said:

Can you experts compare gram/sqft between 66W/sqft HPS and 37W/sqft COBs?

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One will yield about a pound, the other about 16 ounces.

will the real cobcrete standup

30 XP version or 60 up XQ version, 60 up Deep red XQE should be an arse kicker, standard 28mm Citi footprint
Cheers
Mark

it looks like only the 60ups would use holders without interfering with diode layout.

welight said:

will the real cobcrete standup

30 XP version or 60 up XQ version, 60 up Deep red XQE should be an arse kicker, standard 28mm Citi footprint
Cheers
Mark

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These appear to be similar to other cree and epileds boards that are rated from 10-100w. I think it is a nice idea to have some good available colors like Far red, Deep Red on two channels, IR and Royal Blue on two channels, etc. Small footprint can be used as ancillary lighting for additional effects. Must be nice to have the ability to flow diodes.

VegasWinner said:

These appear to be similar to other cree and epileds boards that are rated from 10-100w. I think it is a nice idea to have some good available colors like Far red, Deep Red on two channels, IR and Royal Blue on two channels, etc. Small footprint can be used as ancillary lighting for additional effects. Must be nice to have the ability to flow diodes.

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Try not to rip it off and then demand respect for your open source, k.

looks good built

Any voltage, current ratings?

goofy81 said:

Any voltage, current ratings?

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This deep red version is approx 36V at 700ma, will depend on what led type and mix
Cheers
Mark

welight said:

This deep red version is approx 36V at 700ma, will depend on what led type and mix
Cheers
Mark

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can you make a chip like that swapping a third of the deep reds with a range of UVAs and actinic blues (365, 390, 410nm 420nm etc) ?

PurpleBuz said:

can you make a chip like that swapping a third of the deep reds with a range of UVAs and actinic blues (365, 390, 410nm 420nm etc) ?

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yes, actually got request last night to build 4 just 390nm, what ratio of what do you want?
Cheers
Mark

is 390 the lowest wavelength of reasonable cost/efficiency?

CobKits said:

is 390 the lowest wavelength of reasonable cost/efficiency?

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there are more players now in 365nm but still an expensive chip, would make one of these probably >$300, 380nm may be a bit more reasonable, but right now 390nm is the boundary for relatively low cost vs eff/radiant flux

Can I take one of my cxb3590s off a series of 5 and put a parallel of one of those in instead? I'm pretty sure my c1400 driver has an output of 179v . Which would be enough

**off topic**
@welight why I can choose only 4 ledil angelina reflectors as an option with your CXB359-LHA8-36VKIT considering there are 8 chips and 8 reflectors holders with this kit?