Question about improving LED efficiency.

[CobKits]

how thick is the bottom of it?

 

[Jeremy Pivens]

how thick is the bottom of it?

only about 1/8th of an inch.

 

[CobKits]

thats less than ideal. if you can scab it with something a little thicker it would be suitable for cobs

 

[Jeremy Pivens]

thats less than ideal. if you can scab it with something a little thicker it would be suitable for cobs

Would my big inch and a half thick piece of aluminum be good for cobs? Its 1.5" thick, 7" wide and 3 foot long. It isn't ribbed like a normal heat sink.

 

[CobKits]

on a heat transfer basis from the cobs itself it would be good. on a heat transfer basis moving heat from the block to the air it would be poor due to lack of surface area

 

[Jeremy Pivens]

What if I drilled 1/4 inch holes in a series across the entire panel except where the cobs will be? I would also use 2 PC fans to cool it down a bit.

on a heat transfer basis from the cobs itself it would be good. on a heat transfer basis moving heat from the block to the air it would be poor due to lack of surface area

 

[freemanjack]

can you open it up and look at the drivers?

ill send you better chips for free

Fuckin top man!!!! yer a super star @CobKits this is wot makes growin weed different from any other goddamn capitalist shite; feeling!

 

[Jeremy Pivens]

Fuckin top man!!!! yer a super star @CobKits this is wot makes growin weed different from any other goddamn capitalist shite; feeling!

Indeed. The cannabis community has done alot for me and my girlfriend since her brain injury, after she came out of her coma she has been in pretty much constant pain, the only thing that offers relief is CBD and THC. There are a few companies that have donated cbd products to her since they knew about her condition and realized we were quite poor. You never hear about big pharma donating cancer meds to people in need, that's why I love this community!

 

[freemanjack]

What if I drilled 1/4 inch holes in a series across the entire panel except where the cobs will be? I would also use 2 PC fans to cool it down a bit.

look on fleabay in the pc section, you will often find listings for boxes of second hand cpu heatsinks with fans, most cpu's put out around 100w of heat so just about any cpu cooler will be more than adequate to sink one of Cobkits 40w cobs, they usually go for pennies. As far as conversion, I get yours is a 'discreet diode' rather than cob design but this vid might help;

 

[Jeremy Pivens]

look on fleabay in the pc section, you will often find listings for boxes of second hand cpu heatsinks with fans, most cpu's put out around 100w of heat so just about any cpu cooler will be more than adequate to sink one of Cobkits 40w cobs, they usually go for pennies. As far as conversion, I get yours is a 'discreet diode' rather than cob design but this vid might help;

If I'm going to build another light I will buy one of the 185's off cobkit's website and do it right, I will keep this one whole to start seedlings under.

 

[CobKits]

if thats the case ill send you 4000k 80 chips let me know

 

[Jeremy Pivens]

if thats the case ill send you 4000k 80 chips let me know

Thank you so much man! I really appreciate it and so does my girlfriend, these lights are ultimately going to help keep her out of pain and we are very grateful. I will send my address to your inbox.

 

[coreywebster]

Nice work cobby!

 

[Jeremy Pivens]

Great video man, appreciate all of your feedback! I've been on eBay now for the last two hours checking stuff out. I also have a bunch of copper sheeting I could make a pretty badass heatsink out of maybe. Are they decent for cobs too? I know some PC heatsinks are copper.

look on fleabay in the pc section, you will often find listings for boxes of second hand cpu heatsinks with fans, most cpu's put out around 100w of heat so just about any cpu cooler will be more than adequate to sink one of Cobkits 40w cobs, they usually go for pennies. As far as conversion, I get yours is a 'discreet diode' rather than cob design but this vid might help;

 

[freemanjack]

Great video man, appreciate all of your feedback! I've been on eBay now for the last two hours checking stuff out. I also have a bunch of copper sheeting I could make a pretty badass heatsink out of maybe. Are they decent for cobs too? I know some PC heatsinks are copper.

Copper is a good conductor but ally is better at dissipation, some cpu coolers use a copper plug in the middle of ally fins for the best of both worlds. CPU's have a heat output of around 100w's those cobs were approx 40w @ about 50% total thermal efficiency giving us 20w of heat to dissipate, you can see those heatsinks are nothing fancy but that unit runs cool as a cucumber, if anything the heatsink/fan combination is a touch of overkill on those cobs, passive would have sufficed.

 

[The Dawg]

 

[Jeremy Pivens]

What movie is that from? And as per the quote, are you saying a copper sink will save me more dough in the long run?

 

[nfhiggs]

You never hear about big pharma donating cancer meds to people in need

Actually, they do that quite often. My wife got a year supply of free Humira Rheumatoid Arthritis medication worth about $20K direct from Abbot Labs back in 2010 when I was out of work for 6 months, then another free years supply again in 2013.

 

[Jeremy Pivens]

Wow that is pretty awesome. They need to publicize these things more so people stop hating them so much. I have personally never heard anything positive said until your comment.

Actually, they do that quite often. My wife got a year supply of free Humira Rheumatoid Arthritis medication worth about $20K direct from Abbot Labs back in 2010 when I was out of work for 6 months, then another free years supply again in 2013.

 

[nfhiggs]

Yeah, all of the big pharmaceuticals have such programs, they get very little press because (IMO) it just doesn't sit well with the media's "evil big pharma" narrative.