DIY LEDs - The write-up

[dtech]

Webbrage sounds like a sweet dal you got there congrats, also pics would be cool.I got my heatsink today, and ordered fans, and buckpucks on the way, need to save a bit more for the leds shouldn't be too much longer and I will be putting it together. Question on the optics again, where can I find the 80 deg optics? I may be wanting to run try them at some point.

 

[kcress]

<a href=showthread.php?s=&postid=15144445#post15144445 target=_blank>Originally posted</a> by qfrisco
Thanks, kcress. Great suggestion - I did just that and found exactly where it was. I'm wrapping up my project now - will post pics soon!

Excellllllllent x 2.

 

[jimnrose]

kcress: thanks for your input. Most extrusions are painted but I can't use them because the paint inhibits heat transfer to the aluminum as well as from the aluminum to the air. The mill finish has no coatings thereby ideal for a heat sink. I tried suppliers but the shipping costs are prohibitive. Thanks, Jim

 

[timmmysli]

I've followed this thread and a few other led builds over the years. It's exciting to see so many reefers helping each other out

Thought I would share my cree fixture:

20 white xr-e wc's with 20 deg optics
6 Royal blue xr-e

I'm actually looking to create a spotlight effect and have mounted the leds to suite my aquascaping plans.

 

[timmmysli]

Last lot of pics

Installed mono film screen to help reduce salt problems. The screen also locks in the air flow. I have two 80mm pc fans sucking air through some flat heat sinks, the air then travels down into the led chamber and then exits back up through the fans at the back of the unit.

 

[kcress]

timmmysli; Got any more pictures? I really can't figure out what I'm seeing.
What's the "heatsink"?
Is it just a flat plate?
Did you drill and tap all the holes?
What are your current controllers?
What's the outer frame made of?
What are the raise black do-hickies?

jimnrose; Maybe we are talking at odds. I have never seen extruded aluminum channel/tubing that was painted... Hardware stores often have extruded shapes. They've never been painted that I've seen. They are, however, anodized, usually clear or gold. Are we not talking about the same thing?

Here's an example: http://www.brunnerent.com/Tools/Por...ize=0&lngDisplay=0&jPageNumber=15&strMetaTag=

 

[jimnrose]

Kcress, aluminum is available in various finishes. Hardware stores carry both mill (no finish) and/or clear but in limited shapes and sizes & usually at a pretty high cost. Extruded aluminum that is marketed for storm windows/doors, screen enclosures are available in white or brown/bronze finishes. A local retailer uses milled aluminum channel to fabricate awnings & has a dimensin that I can use for the heat sinks (runs $3.20/ft). Another supplier uses anaodized channel to fabricate shower enclosures but the channel is too narrow. Thanks for all your help. Jim

 

[timmmysli]

In the pic you can see the heatsink. Theres a 70mm hole in the base of the heatsink which is aligned with a hole I cut in the 5mm plate. Air is sucked into the heatsink and down into the base of the led fixture.

I've used buckpucks and advance Phillips xitainium units as well. Although it's a bit more expensive, this way I get to turn on sections of the lighting one at a time on seperate timmers.

Its a flat 5mm plat that I drilled and tapped along with the 70mm air circulation holes.

The outer frame is a kit I found at my local hardware shop (the black box). Hopefully its strong enough to last the 5 year+ mark

This pic should give you an idea of the planned aquascapeing. Theres three areas in the tank I will be lighting.

 

[timmmysli]

Heres my first led prototype

I had a small airblower pushing air into the box section. Air was forced out of the box section at each led lens as the holes cut in the black box were slightly oversized. The ends of the black box were sealed to create enough air pressure. The idea of this setup was to make sure any salt air was blown away from the led lens.

 

[Soundwave]

Very nice, sir. Very nice.

 

[apt220]

For the Crees, does the optic holder fit when the star is screwed on? Or do I need to use the epoxy so that the holder fits?

 

[timmmysli]

Thx soundwave

What can I say thx for such a great thread it has been a good read.

 

[kcress]

jimnrose; Thanks for the comeback. Good idea window shower installer shops. Thanks.

Ah timmysli very nice. Thanks for clearing that up. I am extremely interested in how that well thought out tube with bigger holes worked out! Very creative.

 

[timmmysli]

Here you go kcress



Hope thats the one you were talking about. The vid shows off the airflow thats being forced out around the leds.

I was testing with cheap k2's back then.

 

[timmmysli]

I cut the holes too close together which made it nearly impossible to wire up. I never went ahead with this build because I doubted its ability to remove enough of the heat from the leds. I had thought forcing air through the tube would make the entire tube into a big heat sink. I think the idea would work but I ended up playing it safe with the setup I have now.

 

[jimnrose]

Cree XR-E Stars - can someone tell me what is the size of the substrate? I'm ordering the heat sink material but 'guessing' the stars are about 1" wide. Am I right??? Thanks, Jim

 

[xenia2]

Talking about power supply, sorry if this been covered. But does the wattage matter when picking a power supply?

 

[shackscs]

Ummm...a little help please.

Below is a board I am reworking from off of my Solaris. Going from left to wright, I have solder the 1, 3, and 5th LED together.

On the first LED I soldered from negative to the postive on the 3 LED and then from that LED from the Postive to the Ngeative.

The 2nd and 4th LEDS are the blues are not yet wired.

I tested each LED after soldering and they work fine. However when I wanted to test the string of three LEDS by connecting my 3 x AAA battery pack to the postive on one end and the negative on the other end, nothing happens.

Did I wire this incorrectly? From the readings I gathered this goes from the negative of one LED to the positive of the other and then to the positive of the next......and so on.

Here is a picture, don't mind the holes, they are for the other wiring for the blue LEDS.

Sorry, not sure why the above s is not showing up a picture instead of a link.

 

[xenia2]

Assuming your wiring is correct. Perhaps there is not enough voltage to drive three LEDs in series.

 

[xenia2]

Oh, if you want to connect them in series. Negative go to next negative LEDs, same with positive.