DIY LEDs - The write-up

[Soundwave]

Alrighty. As promised, updated pics.

Please excuse some of the mess. I am battling bryopsis at the moment and I upped my magnesium. I also moved some rock around which disturbed the sandbed. This has created a kind of cascade effect. Mag is killing bryopsis which is putting nutrients into the water which is creating cyano which makes me mad. I'm working on cleaning it up and doing water changes so, hopefully, soon, I'll be back to prettyville.

FTS

Bonsai

Mix of stuff

Check out the commensal crab!

Purple Digi - I've accidentally broken some arms off it but the growth is still pretty obvious.

Orange/multicolor Digi

Yellow Scroll

Moon

Tri color Acro??? Can't wait to see what this thing does!

 

[Soundwave]

Also, I think I've found a limit to LEDs. It seems that I am unable to keep purple monti caps. I had an idaho grap the grew for a short time then just RTNd almost over night. Then I had a larger purple cap that was not the idaho and it was fine for about a week then just up and RTNd within two days.

Those are too expensive to keep trying.

 

[lilmonster]

That looks great!

 

[Soundwave]

Lemme put the digi sequence together so you can see...

And this is one of the beauties I lost...

 

[bigbus]

Just a quick question, what drill and tap size did you guys use to get the stars on? This is the recommended way of attaching the stars to heatsinks right?

 

[Soundwave]

I used a 6-32 tap. I don't remember the drill bit size but I think it was a 5/32". Could be wrong.

I switched to Arctic Alumina epoxy because I didn't want to drill and tap holes for 48 LEDs.

 

[bigbus]

Ya, I am debating that because I figured for a 110 tank, I am gonna need near 120 led's. 60 cw and 60 rb. Thats way too many for drilling. Do you think this is enough for the tank? I havent really figured how i'll space them though, I need them to fit in under 55" or so length heatsink by 8.5" wide.

 

[Soundwave]

What are the dimensions? I would say that it's more than plenty. I'm running 60 right now with no optics and you can see my results above.

 

[scaryperson27]

The only thing that i would have changed in your first DIY LED build, is the cooling design. I would have bent one metal shroud that went across both of the heatsinks, and installed fans on the middle of the shroud to pull the air evenly from the ends of the shroud. You would have also had to have put a piece of metal on the bottom center to make it somewhat air tight. I'm going to read through the rest of this thread seeing as how i'm only on like pg13 of the first split.

In the meantime, I am interested in doing actinic spotlights to target different corals. I am going to incorporate this into a hanging wooden hood I build. A couple of questions that I have are:

-What is the strongest LED, that will give the most pop in color out of the coral? I'm looking for something that when spotlighted can show through a 250w radium

-What kind of power supply do I need?

-How large of a heatsink do I need for these?

-I am looking for some type of swivel to mount these on. Any ideas?

Thanks!

 

[scaryperson27]

You did a terrific job going into this your first time BTW. Thank you for sharing your work.

 

[Soundwave]

Thanks. As for your questions, read past posts. You'll see that I did enclose mine to help with cooling, as well.

 

[bigbus]

<a href=showthread.php?s=&postid=15297489#post15297489 target=_blank>Originally posted</a> by Soundwave
What are the dimensions? I would say that it's more than plenty. I'm running 60 right now with no optics and you can see my results above.

Its about 60 L 18 W and 24 H, I'm pretty sure I'll have to go 120 led's with optics? But the led's are spaced about 2" apart, so at a 60" length, I can fit in about 30 and 3 rows of it or so, so 30x3, 45 cw and 45 rb? I probably would round it down to 26x3 for easy usage with the meanwell's.

 

[noahm]

Just FYI. Cutting aluminum is probably done safest on a bandsaw. Just use some lube to keep it from galling to the teeth. Also use a pretty aggressive tooth pattern with a lower tooth count for the same reason. I can't remember what,s on mine, but its gotta be < 10 tpi.

You will get a cleaner cut on a table saw and it will basically do nothing as far as dulling a normal carbide blade. No need whatsoever for a special blade, just use a combo blade and you will be fine. The table saw is just a bit more dangerous with flying chips etc. so use protection/guards and a featherboard if at all possible. You can even use a circular saw if you clamp the Al to a solid surface.

A recip saw or jigsaw with a carbide blade works very well too, but not as clean as a table saw. Again, use lube on anything thats not carbide or it will quickly get coated with galled aluminum.

Tile saw=no . will just gunk up the surface with galled aluminum and then you will have a useless blade for anything. The RPMs are too slow even if you use an abrasive (not diamond) blade.

A stand up belt sander works well for cleaning up rough edges. Just be aware, that running abrasives on aluminum will make it HOT. Wear gloves.

Just my input since I work with Al all the time.

 

[serhiyi]

You can buy same heatsink from ebay and have it cut any way you need.

http://shop.ebay.com/merchant/barrredboss_W0QQ_nkwZQQ_armrsZ1QQ_fromZ

The price is about the same as on heatsunkusa (probably same sellers), but he cuts it for free. This can save some people time and trouble cutting it at home.

 

[herring_fish]

HeatSink

HeatSink

I am an designer that always goes in a different direction. I have a concept that basically sets up LEDs much like track light system. I would like to ask some fairly rambling questions about heat sinks. I’m dyslexic and I can’t read all of this thread so you may simply direct me to the right date where my questions were already answered.

I would like to know what a safe minimum size for a heat sink would be for a 5 Watt Luxeon V? I definitely want to have enough heat drawn off to give the LEDs a normal life span but weight and space are issues that I must consider.

I would like to use a 1 or 2 inch cut of an aluminum extrusion for each LED. I don’t know how to calculate something like that. It seems like a common “U” shaped channel would work for just one LED. Perhaps I would need to use some door track that had a couple of extra vertical veins to pull off the heat. Do I really need to buy heat sink extrusion?

 

[Soundwave]

Seems like an awful lot of work. I had success with aluminum U channel for putting an edging on things like plywood. However, it probably wouldn't work for the higher amount of LEDs needed for larger systems. I'm very glad I went with the extrusion.

 

[dtech]

anj1204: I am not getting optics at the start, I may add 80deg later but not in the plan at the moment.
Soundwave: It looks great, I have a grape right now under the PC's, it's not growing but lookis ok for being under PC, I hope to keepit up high still and let it grow out up high.

 

[herring_fish]

It's True

It's True

I am a nutty designer but there is a method and a point to what I design and thinking outside the box has served me will. You can see some of my work on my web site. asaherring.com.
It really won’t be much more work than a standard build, if any. I will develop my design further once it is a little better hatched. This design wouldn’t be for everyone but some will find it interesting. But for now, if anyone would help me with my odd questions, I would greatly appreciate it.

 

[kcress]

herring_fish; Why does my web browser think that your link is a bonafide and reported site for attacking my computer? Your site has issues.


There is no way for us to know whether your proposed design will work, as the surroundings are JUST as important as the sink is. I could say yes, then find out you put it in wood box with a single hole drilled in it. Or mounted it immediately adjacent to four others that are all hot too.

Really the best bet is to try it. Make one - run the maximum current you expect to use thru the LED you'll be using. Do this after mounting it in the same orientation you want to use and as sheltered as you expect to be. Watch what happens.

Best results would be with a temp gun or temp probe held on the LED star or a pin on the LED where the manufacturer has denoted the temperature should be taken. See if it stays well below where the maker recommends it should be.

If you can't measure the temperature in any accurate way then see if you can put your finger on the aluminum behind the LED or next to it. Or try to estimate how well the heat is being removed from the LED.

 

[herring_fish]

A few weeks ago, my site was hacked. I was told, by a local reef web site administrator, that some German Reefers are trying to get into American reefer’s sites but I don’ know why. My software does not find anything now.

I understand that I have not explained the rest of the design. I am only asking about this limited area of interest, assuming normal access to air. I was wondering if there is anyone that actually knows the answer already or knows where I can get concise information on how to calculate this before I invest in parts.

One guy put it on a thin walled reflector and it worked. I have seen that some people have put LEDs on simple “L” shaped extrusions. Others have put them on square tubes. How fare away does the heat seem to spread? Is it warm only ½ inch away or is it still hot 3 inches away. I know that it is very subjective but a touch test, by someone that actually has done it, would save me a lot of work and expense.