DIY LED Array build

[sphil876p]

Here we go........

[wesley6610]

How are the corals growing under the LED's?

[sphil876p]

Originally Posted by wesley6610

How are the corals growing under the LED's?

I am trying to dig up/take some comparison shots, but in the meantime...
I believe based on my experiance so far, I have mounted the LEDs too close to the frag rack so most of the corals have grown very light colored. I am still observing growth though, most of the acros have encrusted their bases well and the aussie duncan polyp has sprouted three new baby heads while living under the LEDs.

PICS to follow

[Cracky]

I would like to build one for my 10 gallon.

[sphil876p]

Originally Posted by Cracky

I would like to build one for my 10 gallon.

The small six LED lamp should be plenty of light for a 10g....
It appears to me that they put out enough light to keep my clam happy.
Happy as a clam

I did kind of detail the build process starting a couple of pages back.
If you have any specific questions I will try to help....

[sphil876p]

This is an acro I picked up right after finishing the array...



little while later....



This weekend moved it under the Halides in my Display tank.....

[wesley6610]

Yeah, it does look like the LED's might be too bright or close and bleaching out the coral. I have a pink birdsnest that is doing the same and I have moved it down to sand level for that reason.

[sphil876p]

Here is another one.....
Right after I finished the Array..



a little while later.......



My 2 year old son was helping Daddy with the corals one day while I was not around and fragged a branch off for me, though you can see it has encrusted the superglue base I stuck it into

[wesley6610]

Now I wonder, if the coral is still encrusting and growing, but has lost all of its pigment, how much longer can or will it really be able to survive? I have several corals that the same thing is happening too, but my only options would be to reduce the current from 700mA to like 500mA since I can't lift my array up. Any thoughts or similar scenarios happening to anyone else?

[der_wille_zur_macht]

If it's still growing, I really wouldn't worry about it. Rather than having lost something important, it's probably just displaying a new set of pigments due to the new lights. I've had corals that *completely* changed colors when moved from one tank to another - pink to orange, green to blue, purple to orange. . .

Granted, as hobbyists, when we see something that's pale like that, we immediately assume it's bleached and dying - but given that it is still growing, I wouldn't worry. Corals develop pigments for all sorts of reasons that I wouldn't pretend to understand, and IMHO we are a little too used to jumping to conclusions about their health based on what we perceive to be the "correct" colors.

Since you have two frags of it, how about moving one frag to a lower-light portion of the tank, as an experiment? Or put it in a traditionally-lit tank, or give it to a friend, and compare growth rates.

[sphil876p]

Many times I have purcased frags and the colors changed completely once the coral has acclimated to my lighting/water quality...
These corals were at the bottom of the Dealers frag tank approximately 24" deep under 20k lighting. I do not worry about the coral as long as it continues to encrust its base and exibit the same polyp extension as when I picked it up...
I have tried to keep several birds nest (stylophora) frags going and have not been successful to this point, they always seem to fade very slowly no matter where I place them.

[wesley6610]

Tonight I reduced my current from 700mA to 350mA to see if some of the pigment would return under less intense conditions. I will observe over the next few days and if I can, I will increase the current to 450mA over the course of 2 weeks.

[sphil876p]

I was just able to order three more of the Meanwell ELN-60-48D power supplies with out any problem from Powergate LLC.

The thermal transfer tape from Digikey turns out to be cheaper than I expected. Having read about it on the big LED thread I was expecting over 50$ per 10" x 10" sheet.....
That was LIST price when you order it online it is only 22$ plus tax and shipping....
Total was approx 30$ and enough transfer tape to easily apply 144 stars

linky... http://search.digikey.com/scripts/Dk...ords=BER159-ND

[sphil876p]

Got started on the next fixture this weekend.
I must say that the thermal transfer tape is awesome......
Assuming it does what it is supposed to do in moving the heat from the led to the heatsink, the tape makes layout and mounting a breeze. This new mounting technique saved me 4 to 6 hours and lots of headaches that I experienced with my first build.

[wesley6610]

Can you provide a pic of what it looks like so far?

[sphil876p]

Originally Posted by wesley6610

Can you provide a pic of what it looks like so far?

I cut the transfer tape sheet to width in strips with a razor knife and straight edge...
Then used scissors to cut the individual pieces to fit the star. I just left them square, did not feel like making all of the little cuts....

[wesley6610]

Looks good Phil!

[reeformadness]

The squares should actually help keep your circuits from shorting and keep you from having to strip your wires to close. Nice work.

[wesley6610]

How strong is the thermal tape once it settles in place? Did you need to clean the heatsink and LED before applying the tape?

[magnoliarichj]

dose some AAs

[nitjt]

Phil did you think the tape will be stong enough to hold the stars and optics in place better than skrews?

[nitjt]

Anyone know when we will be albe to the the new Cree XP-G?

[nitjt]

I have seen this kind of tape around on one of these threads pre cut to fit the stars any know where I can get that?

[Hesham]

Originally Posted by nitjt

I have seen this kind of tape around on one of these threads pre cut to fit the stars any know where I can get that?

Pre-cut tape for LED stars is available at;

http://www.luxeonstar.com/precut-the...rc-9-p-461.php

They sell it for roughly a dollar a square. Suggest comparing the material from this site to the material someone else on the thread is buying from Digikey (a great source for electronic components). Datasheet for the material above is at;

http://www.bergquistcompany.com/pdfs...00_12.08_E.pdf

The tape material is very strong - it can be used to hold heat sinks to CPUs. It is not as strong as thermal epoxy which can be considered a permanent mating.

Tapes are typically not as effective as thermal epoxy or grease as they do not fill the microscopic gaps between the two surfaces being mated as well as if you are to use the epoxy or grease. There are very high quality gap filling tape materials available including ones based on epoxy but these can be expensive and require specialized handling. Regardless, tapes are probably fine for our use in LED fixtures especially if we are moving air over the heat sinks.

The white paper below on the Arctic Silver web site gives a good overview of the surface imperfection issue;

http://www.arcticsilver.com/PDF/WhtP...ace_Basics.pdf

Whatever you choose, make sure that the surfaces being bonded are cleaned or else the thermal performance and adhesion will be poorer.

These materials do have a limited shelf life; check with the manufacturer.

[james3370]

Originally Posted by nitjt

Anyone know when we will be albe to the the new Cree XP-G?

found these in a quick google search, but didn't read too much of it LOL

http://www.cpfmarketplace.com/mp/sho...d.php?t=199888

http://www.cutter.com.au/products.php?cat=Cree+XPG