you can remove it if you have a dremel cut a slot in them and you should be able to remove with a flat head screw driver..... old mechanic trick or if you have a snap-on dealer near you. you could get a screw extractor kit

Those tricks work great on larger screws/taps/drills, but with this being 3mm/4-40, it's almost impossible. It's just too small to get any kind of torque on them. Plus, cutting into the heatsink scars the surface where you are planning on mounting an LED.

Holy mother of jesus....

I have broken 8 taps and drill bits during this process, and I still have about 6 more holes to drill and tap.

Long story short, I'm out of taps and bits, so what should I order from McMaster-Carr?

They have masterkleer tubing which is my favorite tubing and good prices on socket cap stainless screws which are way cooler than phillips.

Also sounds like you might want to try some Tap Magic for Aluminum, it smells like Goldschlager but it works great for tapping small holes. Maybe try ordering a bottoming tap or two as well, some people have better luck with them; I get 100+ holes between broken taps with Mcmaster-Carr bottoming 4-40 taps.

whats the next closest bit size to 4-40 that I can use so I can continue with this build?

isn't it something like 1/32"?

You want to use a #42 or #43 drill

so would this work?

here

Yes.

DRILLING/TAPPING ####IN FINISHED!

and


housing is curing right now. Can't wait to show you all tommorrow.

I'm going to finish this project up this weekend, so i'll definitley have pictures up soon.

Quick question, will I need to run a fan on this or not?

sure why not run fans.. it's cheap insurance that the heatsink won't get too hot.. I'd recommend 2 12v fans connected in series.. conveniently your 24v supply will handle this no prob.

Alright so I'm going to head out to radioshack in a few hours and will pic up two fans and 3 DC connectors since I realize I will need the ability to disconnect the fixture in order to do maintenance.

I want to do this, but I don't quite understand.

Do I just wire the whites (both +,- leads) to one, blues (both +,- leads) to another, and then the two fans to another?

Also, can I use any DC cable (the ones with the red, yellow, white connectors) I have lying around? And then I will route that to a project box which will contain the buckpucks, and then that connects to the power supply, correct?

Right. Each connector will be for a different function. If you use the barrel style connectors like that, make sure the ground is on the outer terminal. It's a safety thing.

okay, so I think I'm going to copy sammy's project box design since he is using 2 buckpucks also.

I'll need 2 female connectors on the fixture (1 for white, 1 for blue), 2 male-male cables to connect the fixture to the project box, 2 female connectors to connect the project box to the fixture, 1 female connector for the project box to power supply, and finally 1 male cable to connect the project box to the PSU.

So a total of 5 female DC connectors, and 3 male cables, right?

Also, how do I wire the fans inline with the system? Can I just wire both fans to one string (either the blue or white) before the buckpucks?

just got back from 2 radioshacks... whipped out their supply of coax connectors and DC jacks.

When it comes to wiring the DC jacks (male) do I just stuff the + and - wires into the top, or what?

Take the cable support off the back so that the terminals are exposed. Solder the wires to the terminals, don't twist. Remember, ground on the outside.

Okay, almost done.

Which terminal is positive and which is negative?

Looking at that picture, top negative, bottom positive.

Sooo....

Just plugged it in for the first time and... only 3 out of 12 LEDs worked. None of the RB's worked, only 3 whites.

what should I start to do now?

Start checking for shorts to the heatsink/ground

how would I do that?

and, do you mean where solder touches both the wire and the heatsink?

You will need a multimeter. Check for continuity between the wires and the heatsink. With only a few LEDs lit, it's a good chance that's what it is. Check for screws touching solder or solder pads on the pcb.

ah, I see. so i put one lead of the multimeter on the heatsink and one on the wire, and if I get a reading I need to resolder it, right?


For some reason I had the idea that aluminum was not conductive... derp.

You don't need to resolder. It's more likely that you will have to reposition the pcb so the screw isn't touching any wiring. Are you using nylon washers under the screw heads? If not, that will make life easier.

This thread was extremely helpful. Just thought you guys should know.

I am using nylon washers under the screws, but i have a hard time believing that the wires are touching the screws.

I'll put some pictures up tonight.




its not over yet

Ok, if you are using nylon washers, then check your polarity and you solder joints. You could have some cold joints that really aren't connected properly. Check the LEDs too. Remove them from the circuit, and test them using two AA/AAA batteries (to get ~3v)

Finally pictures.... I have some weird happenings


So here she is in all of her glory:





And here is my soldering job. It's not too great, I feel as this is the main cause of my problems:






Here's where it gets weird. when I plug both jacks in, only the 3 whites come turn on, and for some reason both potientometers can adjust the brightness, but I can tell which one is meant for the blue because it doesn't make too much of a difference.









Now when I take the blue jack and touch the outside of the blue input, 2 RB's come on. And when I plug it in, they don't.

I'm following and thinking what I would do to troubleshoot. Any reason not to test LEDs with 2xAA battery without removing them from the circuit? (unplug everything first, but test each LED while things are still connected?)

your paying a lot for the LEDs almost 2 times as much O.o

wheres the cheapest place to buy?? lookin to build one of these for my 10g but the pricetag is holding me back.

I got my whites from dealextreme for $5 per star, but shipping took a month. I got the blues from LED supply for like $6 something per star.

You could do it that way, but removing the LED from the circuit removes any potential issues during testing (like shorts).


You never seem to have anything constructive to say, do you? Saying he paid more than you can get from back alley place in China is a little late in the game seeing as he already has the array built. Why don't you try adding to the conversation in a way that will help.

How do I check polarity using a multimeter? if it helps, I have this model:



also, when I turn my multimeter to the continuity mode (where it gives me the little beep) and I put both ends on an LED or a wire or something, they light up very dimmly, but enough that I can tell they work.

Checking the polarity of what? The wires? The LED?

Continuity check is also sometimes used as a diode check, which it seems to be on your meter (not on mine). If you are getting the LED to light up during a continuity check, that's good. Means the LED is still alive.

Might also be doubly certain none of your wires are touching the heatsink itself where you soldered to the stars, that could be a possible issue.

I resoldered the joints that were touching the heatsink, but that didn't do anything. Also, I ripped a contact pad off on of the LEDS, can I still use it?

While the system was on, I checked the voltage of the LEDs and the ones on were running at a healthy 3v. I don't understand how only a few random LEDs could be running while no voltage is transferred to the other ones that wired to it.

Have you checked the LEDs that aren't on to see if they are still good? I would do that before chasing ghosts.

Yes. They all dimly light up when I check with a multimeter.

Well, that's a start. I'd still check with two AA/AAA batteries. Make 100% sure that the LEDs will light.

Okay Evil, thanks.

Will do tommorrow.

BEEEYAHHH!

THANKS NANOREEF FOR PIMPIN MY RIDE!

So, does this mean you got it working?

yup, it's working now.

Thanks for all your help evil, this fixture is hella bright, I have a headache right now, but it comes with satisfaction.

sweet lets get some pics of it on the tank!!

Behold:

What ended up being the problem?

My soldering technique was ####e, too many exposed wires and not enough tinning going on. Corrected about 5 wires and then everything was peachy. also, polarity was off on one of the DC jacks.

Excellent, I had been following along and was just about to tell you to check all your solder joints. They looked a little fugly in that pic.

That light looks sweet!

d.

Good work. I took basic electronics back in highschool and the more I read about this stuff the more confidence I get.

Excellent work maiden and Evil keep being god.