My $30, 20w DIY LED

[Phychotron]

Finally got the blue diodes today and hooked them up. I mounted them directly to the heat sink with screws and thermal paste, then ripped off all the white diodes on the flat aluminum and did the same.

Although I planned on using the flat bar with the finned aluminum I avoided that right now to see if its even needed.

I had to line the holes up with the fins. Its fairly difficult without a drill press and proper tools.

I drilled a hole then tapped it and backed it out. It was easy going for the most part

Here's where one broke off. I drilled a 3/32" size hole for most of the job and diligently removed any broken studs with a vice grip. The cheaper Wal-Mart screws broke off instantly, whereas the Home Depot screws held up unless there was a slightly warped hole.

There was considerable warping from the sheet metal screw tapping the hole so when they were all done I sanded the holes smooth.

Applying thermal paste and mounting the diodes.

I also used a small dupont pin connectors with heat shrink tube between the two rails so that I could quickly disconnect. I also added one on the JST connector so they would become completely independent of each other. Moving them around soldered was a pain in the ass.

 

[Phychotron]

Once I wired the blue side I tested it. Of course it didn't work. Only 2 diodes worked at first, one shut off within a few seconds and the other just blinked. I backed the screws out of the diodes to see if they were shorting across the star PCB. They came on when the screws weren't touching the contacts.

I saw this coming but forgot to get some plastic washers. Instead I used some cardboard from a candy-can box to cut out my own washers.

Just the blue, sideways cause ICMAG wipes the exif data without trying to read/correct it first.

With the white mounted I used some of the flat bar aluminum to hold them all together.

the front.


I never should have mounted the diodes and soldered them before I build the frame and had everything secure. The blue didn't work at first because one or two of the cardboard washers was smashed though. It was only 4 and I had already went though that problem so I knew how to fix it right away. Wiring would have been much easier when everything was mounted. It was a constant pain to work with stuff that was all stuck together. And when I remounted the white I had to de-solder everything just to avoid making a mess with thermal paste.

Blue and white

Hanging up.

 

[Phychotron]

Some stats

temperature is at 155 for blue, 165 for white.

18w both sides for a total of 36w, maybe slightly more on a kill-a-watt. I used a meter on the circuit.

Total cost somewhere around $55.

I'm going to call it the VegMaster1000. I'll try and keep everyone posted.

 

[Phychotron]

An update. Been using it for light around the house still cause my plants are not quite big enough to need another light. So in its test period I noticed that today it only had 4 blue on. So I loosened all the screws on the dead ones and it didn't change a thing. But right when I loosened the one on end that worked it came right on. So I'll need to update my washers with some real one's. I was considering using a 2L soda bottle to cut some out of but not sure how it will hold up to the heat. I'll probably test it later when I have an empty bottle.

 

[Phychotron]

Another upgrade and update

The thing always felt really hot whenever I touched it. So I finally added some fans to it. I ripped some used fans out of an old DS100 and wired the power supply in very sloppily just to test it. The fans I'm going to put on screws and have them mounted to the finned aluminum but need some washers to raise them up. For now I've got them on some rubber feet made specifically for mounting those fans in computers without screws.

Found the Kill-A-Watt. The unit pulled 40w (2w per power supply) from the wall without the fans. With fans it went up to 48w, or 4w per fan.

The fans were used but I figure I could buy one 120mm fan and small driver for around $5 which would bring the cost to around $60, or $1.25/watt.

The difference in the temperature is amazing. The thing doesn't get hot at all. The max temperature I could read was 90F, down 65-75 degrees!

The power supplies are nearly cool to the touch now too. I'm pretty much done with the idea of complete passive cooling. Sure, have a much larger heat sink for fan outages but given the effect it has on the lights it seems silly to not have a fan.

 

[Mr Jay]

Hey buddy, any updates on this project?

 

[Phychotron]

OH yea, forgot about this thread. I added some red to the thing. Upgraded it to white full time with the option to turn on blue and red independently. Basically just ordered a few more creebay red's and tossed them in there.

Building it went smoother than previous. I learned a lot like its much easier to drill from the finned side toward the flat side. and take the fans off before doing anything.

The wattage numbers are
white : 26.1w (includes fans)
w&blue: 46.6w (20.5w blue)
w&red : 53.1w (27w red)
w&b&r : 73.3w

I'm also using it in a grow cab I built. First flower cycle is in progress and so far so good. Its in there with a cheaper knock off I made afterward. Plus some side lighting with the cheap diodes as well.

You might notice I broke the cap off the white on a few of them, but they all still light up. Just a different spectrum.

See it in action .. growery.org/forums/showflat.php/Number/824904

 

[Phychotron]

Side lighting added and flower cycle almost over.

Doing alright, a little dissapointed in its performance after 8 weeks in flower. More light needed, but also the plants were not in prime condition. Gonna take some better photos when I chop them down.

The white spots only show up where the leaves actually touch the diodes. 1Cm away seems to be fine.