DIY LEDs - The write-up

[bebereef]

Much better looking anyway!:eek2:

 

[rEd86]

Stu,

I have been wanting to ask you for more details on this:

Is it more just to protect the LED from accidental splashing? You also mention you don't use any heat-sink besides the star mount. It that mainly because you're not running them at full power or were there other considerations?

I just ordered a lot of LEDs from Evil's power by on Nano-Reef and I am now starting to design my "fixture" and I am leaning towards something similar to what you did. I am placing 48 blue LEDs at various locations around my 700g tank to supplement the MH lights. (24 locations in pairs) I want to minimize their footprint so they don't interfere with the primary lighting, plus I want the fixture to be simple to build, install and maintain. That's why your device caught my eye.

Any more info on your approach?

Thanks!

--Ed

 

[dogstar74]

Good Stu, I was wondering if I had done my fixture wrong, as I am using 6 of the LEDs that Soundwave directed us too, and my 10 gallon is barely reaching that type of lighting level. So when you had much more light in a large tank with less wattage.... well I was a bit worried.

Aaron

 

[stugray]

rEd86,

The LEDs are driven at 750mA with no heatsink other than the Starboard.
The stars are glued to a strip of acrylic using JB-Weld epoxy.
JB-weld has metal filler so it is a decent heat transfer material, but not as good as epoxy specifically made for thermal conductivity.

The strips are glued to the dome using silicone.
The dome is held to my light rack by clamping with the nylon screws.

I made the domes from ~1/8" acrylic.
I used a hole saw & cut a hole ~1-1/2" dia. in a piece of formica.
I then drilled & tapped a hole in a piece of starboard to fit a pneumatic nipple.
Then I attached my compressor and a regulator to the nipple.
Set the regulator on zero pressure, lay the square of acrylic on the starboard then heat the acrylic with a heat gun.
Be careful to not heat it too much, or you will bubble the acrylic ( you can seen some bubbles & dimples in mine ).

Once the acrylic is hot enough, place the formica with the hole on the acrylic with the hole centered over the pneumatic nipple & clamp ( work quickly ).

Then SLOWLY apply pressure using the regulator.
You can continue to heat the dome with the heat gun as it forms, just be careful.

I blew out the first one I tried.

Stu

 

[dantimdad]

Question(s):

I am ordering 2 ea. blue and white to use on a desktop nano.

Should I just get the 700ma buckpuck or a 1000ma?

Also, does anyone know where to get a smaller 24v power supply? The one being used in the original parts list would be comically overkill.

One last thing: what is the spacing of the leds in the original post? The tank is 12x12x12. I was thinking about ordering 5.375"x 6" heatsink or should I go larger?

Thanks,
dantimdad

 

[james3370]

<a href=showthread.php?s=&postid=14949429#post14949429 target=_blank>Originally posted</a> by dantimdad
Question(s):

I am ordering 2 ea. blue and white to use on a desktop nano.

Should I just get the 700ma buckpuck or a 1000ma?

Also, does anyone know where to get a smaller 24v power supply? The one being used in the original parts list would be comically overkill.

One last thing: what is the spacing of the leds in the original post? The tank is 12x12x12. I was thinking about ordering 5.375"x 6" heatsink or should I go larger?

Thanks,
dantimdad

mine are just for moonlights & t5 shimmer, but they are over a 30" long tank & spaced 5" apart

power is provided by a 20volt/1amp wall wart off ebay. just add up what yours will do, add 10% & see what you can find on ebay as far as a laptop or printer power supply....should be more than adequate

mine has (5) 1watt blues on a 350ma dimable buckpuck & power supply noted above. there are (5) 1watt white on a 500ma buckpuck & another power supply noted above. they are attached to a piece of aluminum bar stock available at lowes....i'd think for just a few LEDs that would be plenty for a heatsink

quick vid of them still in mock-up form, but you get the idea. they are STUPID bright lol
http://www.youtube.com/watch?v=1Bb7zon3lXQ

previous recap post in pre-split part of thread:
http://reefcentral.com/forums/showthread.php?s=&postid=14835287#post14835287

 

[stugray]

dantimdad,

I would just use the same driver that I used on my night lights.

It is the OS Driver WH-L241-700 ( http://www.osdriver.com/PDF/OSL241-700 L242.700.pdf )
They output constant current @ 700mA up to 8 series 3W LEDs.
They operate from AC input, no need for separate PS.

I got mine from http://www.etgtech.com

They dont show the product on their website, but they will give pricing if you email them.

Stu

 

[dantimdad]

Great! Thanks for the input.

I will get the bar stock after I order the leds and buckpuck.

If this works as well as I think, I just might pony up on an all led system when I build the big tank when I start building the new house next spring.



dantimdad

 

[dantimdad]

stugray,

I was replying when you posted. I might go your route on the driver.

Thanks,
dantimdad

 

[james3370]

<a href=showthread.php?s=&postid=14949838#post14949838 target=_blank>Originally posted</a> by dantimdad
Great! Thanks for the input.

I will get the bar stock after I order the leds and buckpuck.

If this works as well as I think, I just might pony up on an all led system when I build the big tank when I start building the new house next spring.



dantimdad

yeah, seeing how easy it was doing mine & how much output there is, i keep looking at my biocube8 & thinking that i can get a gutted hood for it from nanotuners.com for $60.......lol

 

[rguyler]

I've been reading this thread and it seems that a primary issue is full coverage with good PAR but without spending a fortune. What appears to be a possible alternative is to use partial optics, providing good PAR in areas but provide good coverage for visual appeal. Maybe just use optics on the string that runs down the middle of the tank (lengthwise) and no optics on the strings in the front and back for example. Does this sound reasonable?

 

[kcress]

I'd say the opposite because without optics on the front and back you will be throwing a bunch of light onto the glass which is a waste.

 

[rEd86]

I am going to be trying a mixed approach. I will be placing LEDs in pairs around my tank. One LED will have an optic, the second will not. The theory is that the one without will give me a broad spread, where the one with the optic will pierce the depths and give me better par towards the bottom of the tank. In my situation, I will be using LEDs as secondary, actinic lighting to supplement my MH lights.

I'll post some pictures once the hardware gets in and I start to build it.

--Ed

 

[DeathWish302]

<a href=showthread.php?s=&postid=14948183#post14948183 target=_blank>Originally posted</a> by ReefEnabler
I did use a carbide tipped blade, something from Irwin. Not sure the exact blade I used, but no it did not seem to dull much. You definitely have to use extra caution and go extra slow when cutting thicker metal. Wouldn't want something that beefy to bind the blade. I've never cut any metal besides aluminum and this was the thickest aluminum I've cut.

I dont know if a tile wet-saw would be better or not. Hopefully somebody who has tried one on aluminum will know. Be careful either way.

A tile wet-saw just 'gummed' up with the aluminum shavings similar to using an angle-grinder (or any grinding disk) on aluminum. I've cut ALOT of aluminum up with my dad's work saws when I was building projects in college and had no problems. Honestly some hardwoods, such as hickory, are harder on blades than aluminum. If your in the finish carpentry biz, a little aluminum cutting on your 'good' blades is no problem.

 

[ReefEnabler]

Last night I managed to get 1 of my 3 LED heatsinks mounted and fired up on the tank (thats two strings of ~28v @ ~700ma). All wiring and optics are mounted so just have to attach the rest in the canopy tonight. It kills me to get so close to finishing everything and have to stop, but that's life with an infant

Very pleased with the shimmer they added with my T5s on, and the actinic pop of the royal blue LEDs is just awesome. Ill try for pics tonight

Question for soundwave or anybody else:

I know we discussed how Royal Blue LEDs have almost non-existant Lux (due to lux being most sensitive to green light), but does anybody have information on how a Royal Blue LED should compare to a White LED in terms of PAR? Soundwave, have you taken PAR readings with just the white and just the blue LEDs on to see what % of PAR is coming from where?
I know we expect a blue light to be slightly less, but how much?

 

[AJT]

OK this may be a stupid question but someone has to ask it.

I see a lot of LED lights that are fashioned like a regular lightbulb, it just screws int a regular socket. Obviously one of the reasons people do not use them yet is color combo & PAR.

The more I look online I am finding there are quite a few avail. I have even seen what looks like a SE Mogul but with LEDs mounted instead.

With this many people in the hobby, you would figure we could get a manufacturer to insert the color combos & type that we wanted.

Sounds like a much better longterm solution.

I applaud everyone here in there ability to make their own, however I would be a little afraid of burning my house down.

Very good thread, shows the direction that our lighting is going, finally something that will save a few bucks in the long run. This is coming from someone that has over 1000 watts of MH & VHO sucking electricity & making my chiller run.

Thanks
Andy

 

[therman]

I've been wondering about the use of PAR meters...

I'm not sure your average PAR meter is giving the full story with corals, as I suspect the chloroplasts in zooxanthellae are biased towards effectively converting blue light (since that's most of what light is reaching many corals). So to do a side by side comparison might not be giving the blues a fair shake.

Also, don't these white LEDs function by converting blue light with phosphors? Wouldn't there be some energy lost in the fluorescent conversion to white light? Therefore wouldn't the unaltered blue light being transmitted actually more efficiently transfer the energy to the corals?

I know there was an Advanced Aquarist article a while back about faster coral growth under 20k vs 14 and 10k, which would tend to support these conclusions.

Maybe this isn't the thread to discuss these issues though Thoughts?

 

[desertreeflight]

nice write up..

 

[Soundwave]

I tested just the blues and, if I remember right, they accounted for about a third of the PAR.

 

[fernandokng]

Do you guys put the fans facing up (to take the heat away) or facing down (blowing into the heatsink)? I believe someone said blowing away, but I want to get more opinions on what's most effective. I will be having (2) 120mm fans per heatsink.

Also, do the buckpucks get hot while they are on? I have 4 of them stuck into very small Radio Shack project box, and I don't want it to become a fire hazard because it gets hot, etc.

Thanks.