COB holders - the basics

^^This looks super intriguing. Is this in production yet or is this just pre-production data? Also it looks as though these are solderless? I have super shaky hands and I've wrecked far too many LED arrays, fucking stupid fingers. Its says "Easy pre-assembly by LED fixing lugs" and has the image underneath which pulls up "Single pushwire terminals" so I wasn't quite sure if this refers to the LED connector or the physical wiring of the LED itself.The latter seems to refer to wiring the LED, but I'm not to proficient with engineer jargon. I like this thread, hopefully someone starts using this stuff before I get the chance. I don't really have much free time until the end of next month though

IlovePlants

test the BJB connection, run perfect and easy to install and interchange...
they push evenly over the chip without distortion,ideal it's to use 0.5mm solid core copper cable...
but in other configuration i use a 1mm solid core cable with a little bit of force to insert and run without problem.

......
Instead of tapping ,alternative is ...'punching' !

stardustsailor said:

......
Instead of tapping ,alternative is ...'punching' !

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Nice, Stardust, what are those called and where did you source them? I had asked in another thread about the possibility of self-tapping screws, any thoughts on those? I'm thinking aluminum is soft so selff-tappers should work if I can find them small enough for those holders....??

GroErr said:

Nice, Stardust, what are those called and where did you source them? I had asked in another thread about the possibility of self-tapping screws, any thoughts on those? I'm thinking aluminum is soft so selff-tappers should work if I can find them small enough for those holders....??

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Google " M3 Threaded Metal Inserts" ..
Found them at local tool store ..
( Furnace Black - Zinc Plated -Inox )

Self tapping will probably do also ..
Haven't tried it ..
Why would not work ,actually ?
Try it on a piece of aluminium scrap / old - salvaged heatsink..


Cheers.

stardustsailor said:

Google " M3 Threaded Metal Inserts" ..
Found them at local tool store ..
( Furnace Black - Zinc Plated -Inox )

Self tapping will probably do also ..
Haven't tried it ..
Why would not work ,actually ?
Try it on a piece of aluminium scrap / old - salvaged heatsink..


Cheers.

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Thanks for the quick reply, I found some #4 self-tapping screws, think I'll try them. Like you said, can try them on a scrap piece or somewhere on the sink that doesn't matter if I have a small hole. Thinking they should be easy to tap into aluminum and save trying to tap/thread them in. Not like they need a lot of force to hold these COB's and I'd probably screw up a tap. This would just be mark, drill a smaller diameter hole, and just screw them in...

One more COB newbie question if anyone has experience with these Ideal COB holders. I don't want to f/up my COBs by putting too much pressure or bending them.

What is the most efficient way to insert the COBs into the holder. I understand the two contact points and where they need to touch the holder. The small plastic/wiring "arms" are somewhat bent downwards so I'm having a hard time visualizing the best way to insert the COBs under the contact points on the holders. Wondering what the best method is to mount the COBs on the holders, e.g. Bend those contact points up a bit and slide it in, or go in from a specific angle and slide it under the contacts? Hope I'm making enough sense here to understand what I'm asking... if not give me shit and I'll try and clarify

Put the COB on the heat sink and put the holder over the COB. I can't see how to get it in from the top.

Thanks guys, sounds like (usual) I was over-thinking this, sounds pretty straight forward, cheers.

Didn't watch the video cap'n posted but there is an "arm" on the opposite side of the positive connector and you place the chip against that, (negative side) and you'll notice a "+" in the back of the holder, letting you know what goes where. Push down towards the arm to get the chip in the lip and then press down softly/firmly (all at once, I know) till its seated. Shit will pop out on you if it's not in all the way so be careful.

zangtumtum said:

for CXA30XX it's possible to use
BJB///OEM-LineSpotlight connectors for COB LED modules
I'm waiting some piece to test, the wheelbase to secure it is the same as the IDEAL model.
I overlap the 3D and just change a few tenths.

View attachment 3178836

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Where can one find cob holders?

For me, after messing around with one ideal holder, the advantages of no soldering and interchangeability were outweighed by the PIA it was to tap and thread the heatsink. Plus it meant more tools and my time.
I can see how the holders would do well in some applications, like a large LED panel with multiple COBs.
I make single COB modules and hard mount the COBs to my Arctic heatsink fan combos. since I get those for under $10 dollars I just lump that in with the COB cost and consider them a single item that will all go away whenever that COB dies. I've been using thermal adhesive on my last few, but like Supra said thermal paste does just fine as well and that means the cob remains removable. This IMO is a more K.I.S.S. solution than using holders.

DarthBlazeAnthony said:

Where can one find cob holders?

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I'm in Canada and had few choices, got the Ideal holders through Digi-Key.

How well did the #4 self tapping screws work for you GroErr?

GroErr said:

I'm in Canada and had few choices, got the Ideal holders through Digi-Key.

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How much were they and could you link it?

Staxxx said:

How well did the #4 self tapping screws work for you GroErr?

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Got them, and will be trying self-tappers for the bracket I'm making for the drivers as well, but haven't started the build. Decided on a re-design, I've ordered another 3 heat sinks, 2 COBs, and 2 drivers to make 4 smaller 50W panels and 1x100W. Since they'll all be basically the same and I get side-tracked easily, I'll be building them all in one go over a couple days, like a mini production line. I'm expecting no issues using the self-tapping screws through, not like there's a lot of pressure applied to hold them and aluminum is quite soft so should be an easy way to avoid tapping. Once I try them I'll post back the results.

DarthBlazeAnthony said:

How much were they and could you link it?

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Looked up the price, it was Newark where I got the holders, COB's through Digi-Key. Heres a link to the Newark part number and pricing, they're like $2.27 CAD each. I'm going with thermal grease with the holders, that'll make it easier to change out/modify/repair whether it be COB's, drivers etc. Initially I was going with the holders to avoid soldering but there are a few benefits like above that will make maintenance easier imo.

@GroErr How many watts would your optimal COB setup draw to cover a 4x4 tent? I wish there was a comprehensive guide with parts list.

@GroErr I'll be down to build as well and compare notes. thanks for the info man.

DarthBlazeAnthony said:

@GroErr How many watts would your optimal COB setup draw to cover a 4x4 tent? I wish there was a comprehensive guide with parts list.

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I'm not the guy to ask as I'm trying a build for the first time but there are certainly enough more knowledgeable folks in here that can chime in on your questions.

The coverage question is a good one I'd like to see some opinions on. It depends I think, many are driving these COB's at lower amps which gains efficiency at the cost of wattage output but higher efficiency. So for example if you built 400W running them @700ma, my understanding is each COB would put out approx. 25W (16 COB's) but at higher efficiency and run cooler so should provide longer life. Would that provide greater coverage or simply efficiency/life than say 8 COB's @1400 ma?
If they were my only lights and I was trying cover a 4x4 I'd tend to go with 500-600W. Question would be say 500W being driven @700ma perform/produce better than 600W being driven @1400 ma? Or being so efficient, would 400W being driven @700ma cover this area well?

The parts list also depends on a few factors like my comments/questions above and everyone's designs have variations that can change the parts involved. e.g. Whether you'll be active or passively cooling them has variables. The most common seems to be active cooling using CPU heat sinks and CPU cooling fans. This is likely the lowest cost as the CPU heat sinks & fans can be purchased relatively cheap. But with active cooling you're now having to also power those fans, so you're into more parts and operational cost/overhead for powering those fans.

I'm going to try passively cooling them with big-ass heat sinks. This drove my up-front cost higher but I don't have to deal with active cooling components. Just a preference I have and want to attempt. It comes from dealing with computer CPU fans and power supplies over the years and seeing many of them fail. I didn't want to depend on, power, or monitor a bunch of small CPU fans so I over-enginneered (and paid for!) on the heat sinks to reduce the complexity and dependence on CPU coolers. I likely won't save anything on operational costs for cooling as I expect I'll have to blow some air across them but if needed I can use a larger (or a couple), more reliable fan(s) to do that which is easier than keeping an eye on a bunch of small CPU fans. I'd be Ok with that as it would remove the risk of a failed CPU fan causing COB failures/overheating.

Haven't built them so too early to post a detailed build/parts list but once I settle on the final design and build them I'll post a build including a parts list.