DIY: 80/100W LED Retrofit for Biocube 29!

[verkion]

Hey guys, well I finally picked up my heat-sink on Friday and got to work on it yesterday. Thought I'd show you guys what has been happening!

The heat-sink itself is a big, big sucker! 15"x7.28"x1.25", it weighs in at about 6 pounds! Here are 2 shots of it:



1st I gutted the stock hood. Not too hard. You'll notice that I've already changed the stock 60mm fans to SilenX ones...they will be reconfigured to pump air out instead of the push-pull configuration in this photo.


2nd thing is to make measurements and try to find the best placement for the heat-sink. I eventually found a placement and started measuring out/marking hole locations on the actual heat-sink itself. I drew inspiration from the BC29 modders over at nano-reef, but am using different LED's than they are. Anyhow, after a few hours, (more than a few actually), I got it mostly figured out, and using a screw, marked the center of the holes for drilling.



The fins on the top surface need to be milled...that is proving to be difficult...but fun! LOL...I'll fill you guys in, in more detail below. Anyways, here are the marked out fin milling locations. It will fit a 120mm fan.


Some of you might be wondering why I have to mill the fins. Well, to fit a 25mm fan (almost 1" fan), there isn't really enough clearance between the plastic of the top cover to the aluminum fins to fit the fan. Sure, they have ultra slim 12mm fans but they push too little air IMHO.

And lastly, here is the mock up of the LED locations. Yes, there's a little cardboard piece in the middle pretending to be an LED because that one is on order still. :-P I was going to do a 4 LED system at first but I didn't like the "spread/distribution" of LEDs on the heat-sink. Anyhow, my best guesstimate of light output is somewhere between 8000-10000 lumens from the LEDs. I'm hoping it isn't too bright requiring me to dim the lights, but I can always mod the drivers if so.


More in the next post...

[verkion]

Here's a shot of the completed fans/drivers for the BC29 top. As you can see, the heat-sink is not mounted yet. Some of you might be curious how to get the 120mm fan location to line up. I measured from the pegs that I will be use for mounting the heat-sink to find the heat-sink center location but on the inside of the cover. I drilled a little pilot hole from the inside to the outside, then found a 120mm fan template online, printed it, lined up the centers and presto, there are the centers for the 120mm fan screws. Mark those, drill tear off paper...and figure out how to drill a big 115mm fan sized hole. Well, as luck would have it, the Dremel Trio kit is on sale this week at Home Depot and Cdn Tire, so I got the kit with the circle guide/edge guide and made short work of the circle. Seriously, it was sooooo easy. No funny cut-off discs, no filing, etc.


The part I'm having issue with are the fins in the center that need to be shaved down. I'm partway there (broke the carbide bit that the Dremel Trio comes with), and it looks like I gnawed out the section with my teeth at the moment. I'll post a pic later of what it looks like as a work-in-progress. I need to go to Home Depot and get some metal cut-off discs to finish up on it. That and some grindstone to file/make things nice and smooth after. Incidentally, I managed to dull the crap out of a rather large drill bit after I decided to use it as a rough material remover.

All-in-all, I'd estimate I have about 3-5 more hours of work before it will be done. I need to gnaw out the rest of the aluminum fins, and then I'm going to polish the bottom of the heat-sink which shouldn't take too long. 200, 400, 800, 1500, 2000, 2000+soap, Mr. Clean Magic Eraser, Mezerna Polish. Should be done tomorrow! My fish will be happy because they get to eat again...

Thanks!
verkion

[verkion]

Alright, well, picking up where I left off, here is the photo of the partly chewed through Aluminum fins on the heatsink...yeah, pretty ugly!!!


And, here it is after using the Trio with a router bit:


Problem is the Trio eventually died...i.e. put any load on it and it essentially turns off. I was careful to let the bit cut without slowing the tool too much. I guess I'm going to return it and get another one from Home Depot. It is a useful little tool to have, that's for sure. What drives me nuts is that all the tools have different shank sizes...like WTF? Oh right, company wants to ensure you BUY MORE of their tools. BAH! Anyhow, here's a tank lit up shot. Remember, I'm using 4 LED's at the moment, 3 across the front and 1 in the center in the back. The sides at the back are a little dark but that will be fixed soon. You'll notice that it looks quite different because the light spectrum is different. The plants are also not opened up etc. (and CO2 content is super low), because the lights have been off for about 2-3 days and this is about 15 mins after turning it on to test. LEDs are rated for 6500K or so. PC bulbs were Coralife 10K.


Here's a before shot of the tank as well.


I think the yellows/reds will show up much nicer with the LEDs now. I'll take another shot of the tank in a week or so after the plants have had a chance to "settle in" and get used to the different spectrum, (and after I've changed the water :-P)!

Thanks!
verkion
P.S. If anyone wants a parts list, or has any other questions, let me know!

[SeaHorse_Fanatic]

I am almost 100% sure this will be toooooo bright for a 29g biocube. 100w LEDs will burn all your corals without being completely dimmed down.

You're going with 20-25w LEDs? Wow, that's going to be super bright. My LED guy is figuring that we'll have to dim down my 200w almost 6' unit for my 165g way down, so I would imagine that your biocube would be fine with 20-40w total.

BTW, don't look at it when you fire it up. You'll probably go blind. Not kidding.

[gklaw]

Well, as luck would have it, the Dremel Trio kit is on sale this week at Home Depot and Cdn Tire, so I got the kit with the circle guide/edge guide and made short work of the circle. Seriously, it was sooooo easy. No funny cut-off discs, no filing, etc.

Hate to say but "told ya" While you are out picking up Dremel bits - you may consider trying a rough metal carving bit.

You may want to try taking the bulk material off with a file and coarser sand paper than 200 grit. Fine may not be good as the soft aluminum could gum it up fast. You may find that you won't need to go anywhere close to the 2000 grit which is almost good enough to polish off paint job on your car. Experiment using WD40 for lubricant in sanding - wash off easy with soap.

Looks like you may have enough room to fit a file between the fins. You will be amazed how soooo easy it is to take off aluminum with a file and sand paper. Polish it off if you want with 400 grit sandpaper lubricated with WD40.

BTW, aluminum should not dull a HSS drill bit. It likely just gummed it up.

[verkion]

So...I actually finished up everything today. It's all working, (with 4 LEDs temporarily cause the 5th is still on the way). Anyhow I'll update the reserved post later tomorrow.

@Anthony - It's a freshwater tank, not a Salt-Water tank! :-) I'll probably have to dose 2x the normal EI regime now.

@gklaw - Ended up using the HS router bit that comes with the Dremel Trio...worked well until...Dremel Trio gave up its ghost. Yep, 1 day, barely 3 hours of use and it died. It spins up but as soon as any load is applied to it, it dies. Well, guess its going back to Home Depot! Bah...worst part was that I was not quite done milling the fins down...sigh. So I had to use a file and do some weird stuff to wear down the rest of the Aluminum. In retrospect, a chisel and a hammer would probably have been the quick, @ home way of scraping down the Aluminum. The result wasn't perfect, but I got enough clearance and nobody is going to see that surface anyways. :-P

I'll post pics/the process tomorrow!

Thanks!
verkion

[effox]

You better.

[verkion]

I updated the post above...its been a day since the lights have been running. First impressions? It runs a lot cooler than I expected! I suspect a heat-sink less than half its size would be more than sufficient to handle the heat load. Ah well, I can see why nano-custom's heat-sinks were so thin.

Color is a bit more "yellow" than I'm used to but that's because the Color Temp is lower than the old bulbs. I'm quite pleased with the results actually...if anyone has any questions or wants to do the same for their tanks, let me know! I'd be glad to help. It's actually remarkably easy in the grand scheme of things! Although the initial costs are higher, I'm sure it will pay off relatively quickly. I suspect that 40W of LEDs would have produced the same light output my stock 72W PC bulbs plus they don't need to be replaced for years!

Thanks!
verkion

[SeaHorse_Fanatic]

Yeah, I was thinking 40w would have been plenty for that size tank. Glad its working out for you. I'm going to check out my LED unit Wednesday night.

BTW, do you have your lights dimmed down or are they are full power?

[verkion]

I'm running them at full blast. The drivers I bought ($7 for 1300mA constant current drivers!) are not dimmable. That said, the driver IC has a sense feedback input that I should be able to modify with a Potentiometer to make it dimmable if really needed. Not 100% sure though...need a spare one to test it out. It should work in theory from the specification sheets I have found.

Thanks!
verkion