DonPetro
Well-Known Member
Thats what is kind of if-y for me. I like the .3" base but the cost of the 2.08" is very attractive.
Heatsinks for DIY LED lamps
- Thread starter SupraSPL
- Start date
churchhaze
Well-Known Member
There may be some cases where a thinner base would be preferable.
For instance, lets say you had something ridiculous like a 12" thick base, then 1" tall fins at the top. Thermal resistance is linearly proportional to length. A longer path of aluminum means higher thermal resistance, so a 12" increase in length will actually increase thermal resistance significantly.
A thicker base plate is good for spreading heat, but the less you have to spread heat, the less benefit you get out of a thicker base plate. You may not get much benefit of a thick base plate for vero 10, for example, in fact it may actually be a disadvantage.
In practice, it's hard to go wrong with 0.30" thickness
For instance, lets say you had something ridiculous like a 12" thick base, then 1" tall fins at the top. Thermal resistance is linearly proportional to length. A longer path of aluminum means higher thermal resistance, so a 12" increase in length will actually increase thermal resistance significantly.
A thicker base plate is good for spreading heat, but the less you have to spread heat, the less benefit you get out of a thicker base plate. You may not get much benefit of a thick base plate for vero 10, for example, in fact it may actually be a disadvantage.
In practice, it's hard to go wrong with 0.30" thickness
Positivity
Well-Known Member
Heres some info on the cpu coolers I tested. These numbers are off a CXA3590 2700k running at 1.75a, just about 150w off of one led. Temp probes were simply mounted on the same heatsink surface as the COB. All of my measurements have been nearly the same whether off of the Tc spot on the
CXA itself or simply placed off to the side. Ambient temp. 30c
Dynatron R24. Only one fan speed recorded at 7.5v. Any higher voltage was way too loud. A little louder than the sunon at 7.5v. Maintains 45c
Sunon LM310. Fan upgraded to a 92mm dual ball bearing run at 12v. The included fan didn't control temperatures well at all. Maintains 44c
Sunon for the win. Its relatively quiet and has a nice flat area for just about any led. There are unnecessary holes in the thermal contact area but with a little TIM filled in it should work well enough. Numbers were higher than the 39c I measured the first time around. Holds steady at 44c.
It would have been nice to run a rosewill alongside but i didn't have one available
CXA itself or simply placed off to the side. Ambient temp. 30c
Dynatron R24. Only one fan speed recorded at 7.5v. Any higher voltage was way too loud. A little louder than the sunon at 7.5v. Maintains 45c
Sunon LM310. Fan upgraded to a 92mm dual ball bearing run at 12v. The included fan didn't control temperatures well at all. Maintains 44c
Sunon for the win. Its relatively quiet and has a nice flat area for just about any led. There are unnecessary holes in the thermal contact area but with a little TIM filled in it should work well enough. Numbers were higher than the 39c I measured the first time around. Holds steady at 44c.
It would have been nice to run a rosewill alongside but i didn't have one available
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DonPetro
Well-Known Member
So on a 10"×18" hsu slab i could do many more than 5 vero10; more like 8-10. But for what its worth i may as well use 2 vero18s. Ugh, decisions, decisions.
Hello ,
dunno if it was post ( if it was than sorry for repeat )
There is a lot heatsink solutions for lot of COB , start ect , and display by series , bridgelux vero ect , cree cxa , citizen ...
http://www.led-heatsink.com/
I think to cool the vero29 I'll purchase
I will grab this one http://www.led-heatsink.com/seepricesandbuy.php?subcate=675
dunno if it was post ( if it was than sorry for repeat )
There is a lot heatsink solutions for lot of COB , start ect , and display by series , bridgelux vero ect , cree cxa , citizen ...
http://www.led-heatsink.com/
I think to cool the vero29 I'll purchase
I will grab this one http://www.led-heatsink.com/seepricesandbuy.php?subcate=675
Bueno Time
Well-Known Member
I forget for sure but I think your plan was 300mA for the Vero 10s, so 10 would be roughly 77w dissipation more or less depending on vF (I used 25.5vF which is what I measured my Vero 10s at 300mA in testing.) On 10" HSU profile x 18" long you could run much more than 10 Vero 10s at 300mA, I believe if I recall correctly POS is using 10" x 24" long and has 400w of 3070s running on it with two 120mm fans.
And I would run more Vero 10s vs less Vero 18s but thats just me, should have a better light spread.
DonPetro
Well-Known Member
Hmmm. Thinking i might just grab a bunch of Vero10s since i want to build a few fixtures for around the house anyway.
Positivity
Well-Known Member
Looks like it'd work. Never personally used them before though. Maybe put a T strip in the middle and add a fin directly over it.
If that dosen't cool enough, a small, quiet, 60mm fan strapped on top would do the trick. I'd do both personally since I like them as cool as possible.
Dloomis514
Well-Known Member
I would have the edges pointed up too allow any convection to proceed efficiently
Ace Yonder
Well-Known Member
After watching this video
rob333
Well-Known Member
i have a shit load of psu maybe about 6 lol i wanna look into running some leds off it but how would be the question
Ace Yonder
Well-Known Member
Same here! I've been building computers since the 90's, if I could find a way to re-purpose all the old parts I have lying around I could light a stadium haha.
Abiqua
Well-Known Member
constant voltage not constant current, ...that is why you would have to run CC bucks to power led's [would even have to get creative here, by wiring multiple 12v rails into a series. Their efficiency coupled with the efficiency of the PSU is going to go downhill fast.....
FrozenChozen
Well-Known Member
Completely unrelated side note,
I saw a guy run automobile 75w HID ballasts with 3500k bulbs first using a trickle charger then a computer psu.... Did a well enough grow with it in an old "A-team" van to get himself a thousand watt hps and some other gear...
As @Abiqua said.... you want constant current not constant voltage,
I saw a guy run automobile 75w HID ballasts with 3500k bulbs first using a trickle charger then a computer psu.... Did a well enough grow with it in an old "A-team" van to get himself a thousand watt hps and some other gear...
As @Abiqua said.... you want constant current not constant voltage,
alesh
Well-Known Member
You can use ATX PSU to run you fans and LEDs. Fans can easily go off +12V rail. For LEDs you'd need a buck converter (could be 95% efficient - strings up to 12V - no COBs) or a boost converter for longer strings (even less efficient - about 90%). Older PSUs are also not very efficient - under 80%. Of course there are some 80Plus certificated PSUs but they are not exactly "cheap way to get a lot of power". Another con is that some PSUs need some load on +5V rail in order to have +12V on the other one.
In the end you'd end up with overall efficiency about 70% or less - effectively defeating one of the reasons people use LEDs.
Yeah I got a lot of ATX supplies lying around too.