Another LED project

[evilc66]

You will want to use a thermal paste though, like Artic Silver. Even with the heatsink polished, it will still help situations.

[Marteen]

Yeah Artic Silver will still come off easily with a little pressure. It won't bond the pieces. Are you using 3 screws for each LED? Why did you put the screws at an angle like that instead of across from each other?

[Catfishboy747]

yeah, agreed, use something like AS5 to aid in removing excess heat. A small tube should get you 20-25 LEDs, and can be found at radioshack or online.

 

BTW, I used two screws each LED to secure mine to the heatsink, any more and its really going overboard.

[npain316]

2 screws only. The offset of the screws was by mistake. The others I plan to do across from each other...and it really doesn't matter.

 

I was under the false impression that AS will bond them to the HS. I will get a tube then.

[Marteen]

Remember when using artic silver to only use a very small drop. It will spread out when you apply pressure to the LED. The thinner the membrane the better the heat transfer. They recommend a single BB sized drop for CPU heat sinks so something smaller than that for LED's.

[npain316]

Alright, I've got all the holes drilled and tapped. This was a very tedious process...probably the most time consuming part of the project. I know this has taken too long for some of you (evil) but the wife has been out of town so working on this has been limited as I have been Dad and Mom with my two daughters (both under 2). So I only have had a few hours this week to work on this. Anyway, the pics.

 

 

Shown are just the whites screwed down (these are all I have, blues are on en route).

 

 

The drill bit is a #43 and the tap is 4-40. You can by them as a set at Lowes for under $5, you will also need a tap handle. If you have never tapped a hole before, you must be very carefull tapping holes this small. Go slow!!! Do quarter turns and back it off. I strongly suggest using some sort of lubrication Such as:

 

Next I need to polish the HS up and start soldering. Stay tuned,

 

Cheers, Nick

[Splumph]

Yeah, I didnt use tap fluid...broke the first tap set after the 3rd hole...lol. Seemed to work fine if I pulled it out, and blew it off halfway through the process. Yup, that is the most tedious part of the process

[evilc66]

WD40 and PB Blaster will work in a pinch (FYI for anyone else looking to do this), but Tap Magic is the shiznit.

 

I found the cure for some of the tediousness: a drill press! You can get all the holes knocked out quick, and then all the time is left in the tapping. Still no easy way to get around that.

[Splumph]

+1 to the drill press, you can get em fairly cheap, you don't need a monster for this. Out of all the tools I've bought the drill press gets the most use (although that may change since I got a new top/guard for my radial arm saw )

[evilc66]

Check around at used tool shops. Thats where I found mine. I paid $25 more than you would if you got the cheapest tiny little drill press from HD, and got 10 times more tool.

 

$125 got me a 36" pillar drill, 5/8" chuck, 3-1/2" travel, with a tilting base and a work light. This thing is built like a tank, and HEAVY! Best $125 I have spent in a long time.

[npain316]

Yeah, I could see how a drill press would be sweet. I only had a hand drill.

[Splumph]

I always forget about these...

 

If you decide to do another array in the future

[npain316]

Here it is polished and uber shiny!

 

 

 

Still no Blue LED's ERR...I will start wiring up PS, Buckpucks, Fans and White LED's early this week.

 

My appology for the lethargic pace of this build.

 

Cheers, Nick

 

P.S Evil, when I wire up that LM317 regulator to the power supply. I will wire that up in parallel like the Buckpucks. Correct?

[evilc66]

Yup. Got a heatsink for it?

[Ryan110484]

What is the LM317 regulator and how does it work?

[npain316]

I plan on stopping to Radio Shack tonight to get all of my remaining electrical needs filled. The heatsink being one of them. Thanks Evil!

 

The LM317 is a voltage regulator. I will be using it to power my fans off my powersupply. The JBJ hood fans run at 12V and the the PS will be at 32V. The LM317 et al. will bring that voltage down to an tolerable level. As a product of this regulation there will be heat produced - hence evil's question about a heatsink.

 

Evil has helped me with this, and I will document visually as I assemble all of this for all to see....and for his approval. hehe.

 

One day I hope I have half the electrical chops as Evil. BTW, do you do this for a living? you must!

 

Cheers,

Nick

[evilc66]

I kinda do this for a living, but not quite. I'm an electrical engineer that works on heavy trucks. Electrical, but on a MUCH bigger scale. If you saw the size of wires I deal with, you would freak (do a search for 500mcm cable ). LEDs are just a hobby/obsession of mine.

 

See if you can get the heatsink for the LM317 into airflow. Dropping 24V is going to make it pretty hot. The LM317 has built in thermal protection, so if the fans stop working for some reason it could be the regulator shutting down to save itself. If it becomes a problem, you could mount the regulator to the main heatsink, but you need to electrically isolate it as the tab is the output. Shouldn't cause any problem providing your heatsink isn't grounded, but it's a good just-in-case. Also, the cheap bastards at RS no longer include mounting hardware for the machined aluminum heatsink (don't get the stamped one). It's a 4-40x1/4" screw.

[npain316]

I plan on putting this circuit in a case with my P.S. - it should fit. And that case will have its own fan! probably blowing directly on the regulator.

 

FYI - I just got my Blue LED's!

[evilc66]

Sweet.

[nibs]

Pics. Now.

 

(Please )

[NAL]

I just saw this thread, haha. I'm doing the same project and everything. 12g nanocube, 7 white and 8 blue. So I'll be taggin along. I can't wait to see how you mount it, I have an idea in my head on how I'm going to. Well good luck.

[euphoricgear]

more led project. man makes me want to do my own! :-)

[npain316]

So I have somewhat simplified this project in the past day. I talked with Evil and realized I don't need to run the Voltage regulator (LM317T), because I will be running 3 fans. If it was any other number, I would need to. So here is a quick diagram of what the wiring will be.

 

Right now I'm in the middle of soldering everything, not much to take pictures of at this point. When I start wiring everything else I will be sure to snap a few shots.

[iMaGin3]

okay... so off the power supply you listed on the first page...can you drive 2 buckpucks off it? I am unsure how many leds i will need and can run. I am thinking about the same setup with the blues and whites. my tank is a 5.5g 16" tank. Do you think 10 leds 50/50 would be enough? do you need any sort of resistors, etc?

[npain316]

Yes two buck pucks can be driven off that power supply. You will want to get two buckpucks, one 700mA (for the blue LEDs) and one 1000mA (for the whites).For you tank 10 LEDs (50/50) would be good. You could go as many as 8.

 

If wired in parallel to the power supply, you add the amps - so this would be 1.7A, well under the 4.2A rating of the power supply. I also will run 3 fans (shown above) wich will draw 450mA. So I am still good.

 

You will not need any resistors, all of the controling is done in the buckpucks which have poteniometers for you to manual adjust the the power going to the LEDs. This will allow you to create the color temp you desire.

 

Any more Q's - let me or any of the guys with the fancy LED banners know,

Nick