# SMD LED tape based light fixture



## hoppycalif (Apr 7, 2005)

It can be a lot of fun making your own light fixture, but it can and usually does, cost more than a commercially available light fixture. However, if you use SMD5630 LED self adhesive tapes, you can possibly keep the cost down, and still enjoy a good DIY project.

I made such a light fixture a few years ago, with mixed results. It did work, but I had a lot of trouble keeping the tapes sticking where I put them. And, it took a lot more of the tape than I expected. Now, I'm pretty sure I'm going to give it another try.

This time I plan to use extruded aluminum channels, and angles, as the heatsink/base for the LEDs, to act as reflectors to amplify the light from the LEDs. (My last light used an aluminum foil lined shade as a reflector to amplify the light.) I will mount the LED tape inside the channels (actually angles), so the sides of the channels reflect stray light down to the tank. Each row of LEDs will be inside a 1" x 1" aluminum channel. Using the data I collected from my last light I think I can get about 50+PAR, at 36 inches distance, from 8 rows of SMD5630 LEDs.

To keep the tapes from breaking loose from the aluminum heatsink, I plan to use beads of silicone cement or epoxy at the edges of the tape to help keep the tapes where I put them.

If all goes as planned (please stop laughing!) this will cost me about $100 total for a 32 inch long light. As I go along I will be posting photos and sketches to chronicle my adventurous fun!


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## hoppycalif (Apr 7, 2005)

This is a sketch of my design. The channels are aluminum 1 x 1 angles. The bracket holding it is made of 1/2x1/2 x 1/8" thick aluminum channels, so the power cable goes over the top, in the channel. And, this mounts to a drawer slide, attached to the back of the stand, to let it move up or down.


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## hoppycalif (Apr 7, 2005)

I just purchased 4-8foot long 1 x 1 x 1/16 aluminum angles - $26.50. Now, I'm committed!


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## Gone missing (Aug 26, 2017)

Interesting project and something that I have toyed with but never moved. Glad to see somebody actually doing rather than just thinking, like myself! 
Any chance the metal is thin enough or the LED protrude enough to drill at each LED and mount the tape on top rather than fighting the fight to stick it on?


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## hoppycalif (Apr 7, 2005)

Gone missing said:


> Interesting project and something that I have toyed with but never moved. Glad to see somebody actually doing rather than just thinking, like myself!
> Any chance the metal is thin enough or the LED protrude enough to drill at each LED and mount the tape on top rather than fighting the fight to stick it on?


Thank you! That is an interesting idea. The LEDs are 5.6 mm x 3.0 mm, not circular, but rounded corner rectangles. The light will have about 500+ LEDs, so it would take that many precisely located and sized holes for this to work well. As a garage corner workshopper I lack anything that would let me do that. The angles are made of 1/16 inch thick aluminum, so I doubt that is thin enough to make it work anyway. If I had thought of this before buying parts I might have found a way to do this, but now I can't. Also, I found it tedious to cut 11-30 inch long aluminum angles, deburr all of the edges, clean each piece thoroughly, drill all of the needed holes in each piece, etc., so I'm sure I would never be willing to do anything 500 times!

My $100 budget isn't holding up too well. I have already spent $101, and have at least $10 more to buy.


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## hoppycalif (Apr 7, 2005)

Has anyone used Sugru - https://sugru.com/getting-started/how-to-apply-sugru-to-a-smooth-surface? It looks like it would hold the edges of SMD tapes down very well and be pretty easy to use.


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## hoppycalif (Apr 7, 2005)

Eleven 30 inch long pieces of 1 x 1 x 1/16 aluminum angles.










The angles all stacked up to make 10-1 x 1 channels.










With the 10 inch long 1 x 1 angle end piece. Nothing screwed together yet. The LED tapes will go inside the channels, with the flat bottom of the assembly being the top of the fixture.


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## Gone missing (Aug 26, 2017)

With you on the idea that 500 holes is too many! I had not figured how many that would be. I find it is often easy to think but it gets harder when we come to "DO". 
Heat does make the choice of adhesives more difficult. 
Some kind of industrial stuff like used on engines? Any idea how contact cement might do with heat? I suspect the expansion of the aluminum requires the adhesive to have some give to it to stay long term?

Thinking and looking at adhesives, would this be anything of value? 
https://www.amazon.com/Permatex-25905-Contact-Cement-1-5/dp/B000ALDYPM
Heat and water resistant!


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## hoppycalif (Apr 7, 2005)

I can't use an adhesive, or even double sided tape, because I would then have to remove the existing double sided tape, without damaging the LEDs. Otherwise, the double sided tape would just release from the LED tape later. My idea is to get the best bond I can from that existing double sided tape, and use a bead of some kind of sealant along the edges of the tape so it takes some or all of the weight of the LED tape.

I was looking for a silicone product that comes in a tube so I could extrude out the bead easily. That lead me to the Sugru, which I had never heard of. It seems to be more expensive than it could be, but if it actually works as well as it is advertised to work it would be worth it. I have used silicone bathroom grout for similar purposes, but the Sugru might be easier to use.


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## DutchMuch (Apr 12, 2017)

following.


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## hoppycalif (Apr 7, 2005)

After drilling and deburring 78 holes, I finally got the heatsink assembly screwed together, with all of the wire routing holes in place! I still need to find my sockets in my mess in the garage, so I can finish tightening all of the screws, then filing the edges of the end pieces to fit better, then thoroughly cleaning the aluminum, then designing and installing the cantilever that will hold this above the tank. Only then can I start sticking the LED tapes in place. It's a good thing I enjoy this stuff!


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## Gone missing (Aug 26, 2017)

How warm do you feel this is going to be? That was my first thought when looking at adhesives, silicone or tapes to use. I find one way to release lots of silicone and adhesives is heating them. 
But for that I'm using a torch and that may leave a wide spot where the heat from LED is not enough to matter while a torch would be much hotter.


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## hoppycalif (Apr 7, 2005)

I doubt the heatsink will ever get above 110F. The last one I made didn't ever feel more than slightly warm. Silicone caulking is good to a much higher temperature than that. The self adhesive tape on the LED strip might eventually give way at that temperature, which is why I plan to rely on the silicone caulking to hold the LED strip to the heatsink.


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## Gone missing (Aug 26, 2017)

Silicone is definitely the easier way to go then!


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## hoppycalif (Apr 7, 2005)

The cantilever beam that will support this over the tank is now installed. Now I need to work on attaching the drawer slide system to the stand, to hold the light.


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## DutchMuch (Apr 12, 2017)

Looks really good hoppy, good luck!


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## hoppycalif (Apr 7, 2005)

After several attempts to design this I finally found something that will be possible to make, will fit, and can be installed without emptying and moving the tank. Here is the vertical support bar, with the drawer slide attached:







and the bar temporarily in place behind the tank:








The bar is a 3 foot long 1x2 poplar board. There is just enough room between the drawer slide an the back of the tank to attach the light support bracket (I hope!)

The hardest part of this has been working inside the tank stand, at the back of it. I'm a bit past the age where this is easily doable.


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## hoppycalif (Apr 7, 2005)

I gave up on the cheap support cantilever bar - It was looking bad, and was too difficult to get all of the pieces to fit together right, plus I accidentally made it an inch short. So, I spent another $12 on a 3 foot length of 3/4 inch square aluminum tubing and made this one, which looks a lot better and is the right length.

My total costs are now $129!


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## DutchMuch (Apr 12, 2017)

130$ isn't that bad really. Especially SO FAR for an LED DIY light. What was Seans total cost to his like 1500$? plus he never finished it.


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## hoppycalif (Apr 7, 2005)

The new cantilever beam attached to the heatsink. I think next will be attaching this to the drawer slide, but that's not for today. If I haven't mentioned this, the wiring all goes down the center of that square tube, to the 12 VDC power supply under the tank.

$130 isn't bad, if this does what I expect it to do, and I again checked my calculations on what PAR I can get, and still think it will do it. Of course this is also more entertainment than a NBA game, for me, so I suppose you could just write it off as part of my entertainment budget.


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## DutchMuch (Apr 12, 2017)

lol!
What color spectrum are you going for? RGB's on there I suppose?


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## hoppycalif (Apr 7, 2005)

The white LEDs are "6000 to 6500K", so I expect they will be warmer than cool white, not as blue, but still typical LED spectrum. In addition I will have 2 rows of SMD 5050 that use 4 or 5 660nm red LEDs to 1 blue (near 400 nm), so they are sold for horticultural use - growing pot I suspect. I'm hoping this will give me good reds so both fish and plants will show off their red colors very well. I will have 8 rows of the white, and two rows of the horticultural LEDs. Since the 5050 LEDs give about half the intensity of the 5630 whites, so the two rows should give about 10% of the total intensity. I have never tried the horticultural LEDs before, so I will see the result only after I get it all assembled. I'm using one 12 VDC power supply, with 8 amp rating, to drive all of the LEDs - all of the individual LEDs will be in parallel.


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## DutchMuch (Apr 12, 2017)

sounds really nice. Your going for some nice PAR to in the long run, ill be truly disappointed if you don't document (make a journal) of your tank afterwards


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## hoppycalif (Apr 7, 2005)

I probably won't do a tank journal. My goal is to have the light suspended about a foot above the tank, and get about 55-60 PAR light intensity. It looks more likely that I will get the PAR, but with the light only a couple of inches above the tank.


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## DutchMuch (Apr 12, 2017)

r.i.p me

lol.


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## hoppycalif (Apr 7, 2005)

The light fixture is now attached to the drawer slide, which is attached to the post which will soon be attached to the tank stand. I have almost zero extra clearance behind the tank for this.

EDIT: After playing around a bit with this I find that the support "pole" attachment to the heatsink isn't stiff enough. The heatsink can move too easily in a rotary way and in a tipping up and down of the ends of it. So, it is back partly disassembled again and some stiffening of that joint is being added. It did look like this would be a problem, but I thought it was just stiff enough.


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## hoppycalif (Apr 7, 2005)

At 3:00 am this morning, my brain woke me up shouting "you can't do that, it won't work!" My brain apparently was working all night on this project, and glommed onto the idea that I was going to put the power cable inside that aluminum tube. The reason it won't work is that wire is rated for current carrying capability based on being in the open air so it is air cooled. Once you bury the wire inside a tube of any kind it loses that air cooling, and you need a much larger diameter wire to carry the same current. If you are using 120VAC power the current per watt is one tenth of what it is when you are using 12VDC, as I am. So, yes a 120VAC wire can be inside a tube with little problem, if any, but with 12VDC you run into overheating problems. The wire insulation would be overheated, the insulation would get hard and crack, and the voltage loss due to the wire resistance would drop the voltage at the LEDs by too much. If I try to use larger diameter wire I won't be able to ever get it through all of the bends in the path to the LEDs, a very hard job in any case. So, I have to run the power cable outside of the support tube. I wish I had thought of this sooner. I gave my brain a severe talking to!!


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## Michael (Jul 20, 2010)

Behold the power of the subconscious!


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## hoppycalif (Apr 7, 2005)

A few years ago I made a different type of light using SMD5630 LEDs, and got a lot of data on how much PAR they produce. I used that data to predict what this light will produce, at the 30 inch distance I want to use it for. That other light used 24 inch long strips of LEDs, while this one will use 30 inch long strips. We have Finnex data showing that longer strips of LEDs produce more PAR than shorter ones do. Using that data, very conservatively, I adjusted this projection for the longer strips. It looks like I should get about 50-55 PAR, which was my goal. It will need 10 rows of LEDs instead of 8, but I have enough room and LED strips to do that.










Of course the proof will be when I finally get this done!


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## DutchMuch (Apr 12, 2017)

interesting. 
Thanks for updating so frequently! 
I just cant wait to see it done! I'm all about end results. Nice graph btw.


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## hoppycalif (Apr 7, 2005)

I got all of the LED strips installed, using just the self sticking tape on the strips. It went pretty well - I had washed the aluminum surface with alcohol, then used a Mr. Clean sponge to wipe it down good, then used very fine grit sandpaper to again clean the surfaces, then used water with dish detergent to wash the surfaces, and finally used alcohol and the Mr. Clean sponge to again clean it.

After sticking each strip in place I used sand, my left over Black Beauty blasting grit, poured over a paper towel barrier to weight each strip down while the adhesive cures.










With all 10 strips stuck in place it looks weird, but it should work out well.










How long should I let it sit to get the best permanent adhesion? I doubt that anything longer than an hour would be useful, but I can't find out what the manufacture recommends.


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## DutchMuch (Apr 12, 2017)

why not just do it over the night? I'm sure it couldn't hurt. looks good btw.


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## hoppycalif (Apr 7, 2005)

I have looked everywhere I can think of, googled the subject, and I have not yet found any tips of any kind for how to get the best bond using those LED strips. Scotch totally ignores the subject, as does 3M. I know that leaving them weighted down for several hours can't be harmful, but I also doubt that it is helpful. The whole idea behind the doublesided tapes is that you get instant gratification. I feel a need for gratification before tomorrow. But, I decided to demonstrate my steely self control by waiting until mid morning tomorrow.

Then I will demonstrate my "belt plus suspenders" tendencies by applying my silicone caulking along the edges of all of the strips.

Incidentally, the horticultural LED strips have double sided tape that is obviously deficient, which tends to explain why they were so cheap. The silicone caulking should make them work fine, too.


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## DutchMuch (Apr 12, 2017)

if it is one thing I have learned in this hobby so far,
its that, most thing that cost $$$ are worth it. *cough* TWINSTAR *cough*


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## hoppycalif (Apr 7, 2005)

The sand weights seem to have worked OK. At least all of the strips are glued down, except for about a 4 inch length of the horticultural LED tape, which I noticed wasn't holding the tape very well at the start. I expect the silicone caulking to compensate for that part. Notice how the sides of the channels act as reflectors, which will increase the amount of light delivered to the tank.

Now, I need to do the hard part - solder the wires to all of the strips. These are all waterproof strips, so part of that is scraping off the clear plastic cover off the solder pads. Just 20 places to scrape. About two weeks of work???


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## DutchMuch (Apr 12, 2017)

haha good luck!


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## hoppycalif (Apr 7, 2005)

I'm thinking about the complete LED electrical circuit now: I know from experience that much is gained by applying power to both ends of a long string of parallel LEDs. But, which of these two circuits is best, or is there a better option? Perhaps combining the two circuits? The goal is to reduce the voltage drop from running all of the current through the long printed circuit paths.


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## Hillbilly Homer (Sep 25, 2012)

i would go with your 2ed circuit diagram.
1) When one of the strings fail it will be much easier to trace down the problem. 
2) When a string fails you wont lose all your lights.


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## Uncle_R (Sep 1, 2017)

Definitely #2. 


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## hoppycalif (Apr 7, 2005)

I think I agree on #2.


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## hoppycalif (Apr 7, 2005)

It took two days to complete the stripping of the coating on both ends of each of the 10 strips of LEDs. One good thing is that this is a learning process - it gets easier after you do a few of them.



















I may have to clean the solder pads a bit more, but the next step is tinning each of those pads, 40 of them!


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## DutchMuch (Apr 12, 2017)

well you got the first part done... Good luck!


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## hoppycalif (Apr 7, 2005)

All solder pads tinned! The pads are so tiny the solder makes tiny balls on each pad instead of coloring the copper pad silver with the solder. I think I will put a small piece of electrical tape between the solder pad area and the heatsink, just to be sure none are shorted to the heatsink.

I ordered the hookup wire from Amazon, and it arrives tomorrow, so now I rest!


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## Uncle_R (Sep 1, 2017)

Did you use a rosin core solder or flux when you tinned?


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## hoppycalif (Apr 7, 2005)

I use small diameter rosin core solder, as recommended by the manufacturers, and the wattage soldering iron recommended by the manufacturers. It was pretty easy. Next I will tin the hookup wires and solder them to the pads. I belatedly realized I should have tinned only half of the pads, but no harm done by doing them all.


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## Uncle_R (Sep 1, 2017)

That's good to hear. It is hard enough to tell if a solder joint is cold in person let alone from a picture. From the "roundness" of the solder I was concerned that it didn't flow onto the pad. 


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## hoppycalif (Apr 7, 2005)

Each end of the strips now has an insulating tape piece between the strip and the aluminum, which should stop any short circuit that might have happened. The rounded balls of solder made me wonder if I had cold joints too, but doing this little taping job required that I pry up the end of each strip, hard to do, and only one of the little balls popped off. It seems to be the only cold joint I had. One of the DIY how-to-do-it articles I saw showed this same ball effect after tinning the solder pads. Even the tiny amount of melted solder on the tip of the soldering iron was way more than it takes to tin the copper, so the excess forms the balls. The thing I wonder about is whether that may spread out when I solder the wire to the pad, shorting the pads. I'm not really very good working with such tiny things.

When I solder the wires on I may find that I have a lot more cold joints, but I like to assume the best not the worst.


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## Hillbilly Homer (Sep 25, 2012)

May i suggest testing the lights before wiring them up...


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## hoppycalif (Apr 7, 2005)

Hillbilly Homer said:


> May i suggest testing the lights before wiring them up...


Nah! I'm mr Positive Thinking! I just finished wiring up the positive wires - the wires on one end of the strips. That is very difficult, but as I go along I have learned to do it better so it is getting a little easier.


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## Maryland Guppy (Mar 5, 2015)

You are surely through the worst part.
Removing the silicone type covering from the strip absolutely sucks!


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## Michael (Jul 20, 2010)

One of the great things about the aquarium hobby is that it appeals to so many different interests. Some people really love the technology involved, and there is no end to DIY gadgets to entertain yourself with.


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## DutchMuch (Apr 12, 2017)

true true...!:grouphug:


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## hoppycalif (Apr 7, 2005)

As I told my wife today, if I had bought a ticket to one NBA game I would have had about 2 hours of entertainment, and it would have cost me about as much as I have spent on this project, which is now up to $135, but it has entertained me for about 3 weeks now, with more to come. She didn't object to the dollar cost, but wondered how I will react if it doesn't work - but, I will still have had the entertainment.


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## DutchMuch (Apr 12, 2017)

again, 
True true!!


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## hoppycalif (Apr 7, 2005)

All of the strips are connected now. I have the 10 strips connected in parallel and each strip has about 42 LEDs internally wired in parallel. So each LED has 12 volts across it, with the internal ballast resistors setting the current.

I am still figuring out how to tuck the 3 wire soldered connections at each end of each strip so they aren't easily visible.


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## hoppycalif (Apr 7, 2005)

It works! I have the power supply temporarily connected, to see if it works and to measure the PAR I'm getting.










This next one shows the effect of putting the LEDs down inside an aluminum channel.










With the light clamped to my workmate bench, with the light 33 inches from the floor, I get about 23 PAR: With the PAR meter raised so it is 20 inches from the light I get 53 PAR. These are much lower than I expected, and lower than it looks to the eye, which is a very inaccurate light meter.

The reason for the low PAR numbers is what you see in the second photo above. Far too much of the reflected light is reflected out of the area I want to light. Ideally that photo would show much less light. I didn't make enough allowance for this effect. If I compare my results here to what I measured with another LED light where no reflector was used, the PAR readings I have are very close to what I should have expected. Now I need figure out the best way to get more light reflected towards the water.










The light looks pretty violet here, but to the naked eyes it looks just slightly blue white. Pretty much like any other relatively cool white light.


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## Hillbilly Homer (Sep 25, 2012)

=D>


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## DutchMuch (Apr 12, 2017)

wow, looks very good!


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## Uncle_R (Sep 1, 2017)

Nice payoff for your hard work. 


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## hoppycalif (Apr 7, 2005)

It is a disappointingly low light compared to what I expected! But, I think I can change horses here, and plan on using this sitting on top of the tank. Then I should get very close to what I was aiming to get, and not have nearly as much spilled light. Much of that spilled light should hit the front and back glass and get reflected back into the tank. That could possibly raise the PAR above what I wanted. Using it this way I could use the drawer slide light elevator just to raise the light out of the way for maintenance. (I make good lemonade!)

I have started applying the silicone caulking to the edges of the LED strips - a very slow process, so that will take another day just to complete that part. I will also use the caulk liberally to hold the hookup wires at each end of each strip.


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## hoppycalif (Apr 7, 2005)

The Silicone caulk is all applied. I ran a "bead" along each side of each of the 10 LED strips, hoping it will help prevent the strips from coming loose and dropping down over time. It looks pretty sloppy, but it won't be at all visible when the light is in use. I'm still thinking about what to use to "pot" the electric connections at each end of the strips.


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## DutchMuch (Apr 12, 2017)

Electricity newb here:
what do you mean by "pot" it?


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## hoppycalif (Apr 7, 2005)

DutchMuch said:


> Electricity newb here:
> what do you mean by "pot" it?


"Pot it" means enclosing it in a blob of some kind of concrete, silicone, epoxy, etc. I ended up deciding to just use small blobs of silicone caulking and bits of electricians tape to hold the wires where I want them.










Tomorrow I plan to finally install this over my aquarium, measure the PAR I get with it sitting on top of the tank, and rationalize whatever it turns out to be as exactly what I wanted


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## DutchMuch (Apr 12, 2017)

!


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## hoppycalif (Apr 7, 2005)

Temporarily on the tank!! But, the PAR is very hard to measure because the plants shade the sensor too much. I get a reading that is lower than the actual PAR.

I need to permanently install the light before I try to do any more measuring. At least the appearance is very good.


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## hoppycalif (Apr 7, 2005)

The light is now fully installed, looks great. The heatsink does get very warm, not too warm to keep your hand on it, but definitely warm. I can see that the lighting is more uniform than it was with the Finnex Planted Plus I have been using, and the reds are more evident, so perhaps I can get better growth with this. My expenses in building this are:


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## DutchMuch (Apr 12, 2017)

135$, not that bad! Not bad at all really. Especially when its pretty much Exactly what You are looking for.


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## hoppycalif (Apr 7, 2005)

What I wanted was about that same PAR, but with the light 10-12 inches above the tank. It would take lenses on each of about 400 LEDs to make it do that. That would be beyond anything I could do. Or, I could use about a 6 inch aluminum extension all around the tank, to act as a focusing mirror. That would be possible, but not what I am willing to do. SMD strips are made to spread light over a large area, not to light up a small area with high intensity. Even then, if I had a 40B tank this would have worked just about as I wanted, but a 24 inch high 65 gallon tank has to have a more focused light.

EDIT: Rethinking this: The Apogee PAR meter reads about 8% low in water, and it reads only a small fraction of the light in the 660 nm region of the spectrum. So, I very likely am getting the 50 PAR I wanted. Next time I do tank maintenance I will try to shove some plants aside and see if I can get a better reading of the light in the middle of the tank, at the substrate.

EDIT2: I just measured the PAR, and to my surprise, the PAR at the front glass at the substrate reads 50!! Near the center, front to back, it reads about 39. This is the effect of the front glass reflecting so much of the light that has reflected off the heatsink walls, back into the water near the glass. Add 8% to correct for the effect of the water and it would be 54 at the front glass and 42 in the center. Add about 5% for the 660 nm red that the PAR meter doesn't pick up, and it is about 57 at the front glass and about 44 at the center. These are very much in the range that I was hoping for. I'm going to assume that my light is now 45-55, or medium light.


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## hoppycalif (Apr 7, 2005)

This chart shows the PAR I get from this light. The readings in the air were done with the light propped up in my garage. The distances are accurate to about 1 inch. The reading in water was taken in my planted tank, off center left to right, to avoid reading directly under the cross brace. It is roughly centered front to back. The reading was corrected for the PAR sensor's 8% low in-water error, caused by refraction across the water to plastic lens interface on the sensor. Since this sensor reads only a small percent of the light in the 660 nm region, and this light has a lot of light in this region, the actual PAR is probably a few percent more than the readings indicate. But, this is useful for deciding how useful these LED strips are for whatever height tank you might want to make a light fixture for.


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## Michael (Jul 20, 2010)

Very interesting. Your comment about the light being more even than the Finnex Planted Plus points out my only criticism of that fixture. The spread is even at the bottom of the tank, but tall plants at the back do not get as much light as tall plants in the center.


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## hoppycalif (Apr 7, 2005)

Yes, the narrow bar lights do leave the upper, front and back corners low on light. I see that in the fact that taller plants tend to grow towards the center. And, it probably does limit one to lower light plants than you would think. It would be true for all of the 3 inch wide bar lights, not just the Finnex lights. I think the ideal light, sitting on top of a tank, is one that is almost the same size as the footprint of the tank, so it spreads the light uniformly over the whole tank. But, the best light is still one that is suspended a foot or more above the tank, but doesn't spill light outside the tank footprint. That gives you more uniform lighting from substrate level to water level, as well as relatively uniform front to back and left to right. Perhaps some day I will again try to make one like that, and actually succeed!


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## Michael (Jul 20, 2010)

Makes sense. Do you think that adding another Finnex fixture would increase the light out of the medium category and into algae farm range? I am thinking about my 75.


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## hoppycalif (Apr 7, 2005)

Michael said:


> Makes sense. Do you think that adding another Finnex fixture would increase the light out of the medium category and into algae farm range? I am thinking about my 75.


I think it would get you into high light, but probably manageable high light, if they are Planted Plus lights.


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## Hillbilly Homer (Sep 25, 2012)

How hot is the light getting? 
i like your design and thinking about making one but with using 3w leds and lenses insted of the light strips.


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## hoppycalif (Apr 7, 2005)

Hillbilly Homer said:


> How hot is the light getting?
> i like your design and thinking about making one but with using 3w leds and lenses insted of the light strips.


It gets very warm. I can keep my hand on the top without extreme discomfort, but it is close to being too hot. I would not use 1/16 inch thick aluminum extrusions with 3 watt LEDs, because you need more heat sink capacity with that wattage LEDs. I would use the idea of forming channels by putting angle aluminum side by side, but with 1/8 inch material. And, I would probably use at least 1.5 inch angles, not 1 inch. I think that would work very well.

I have made a couple of lights with 1/8 inch thick aluminum channel extrusions, with the LEDs mounted inside the channels. I used 2 inch or bigger channels for those, and they didn't get more than slightly warm.


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## hoppycalif (Apr 7, 2005)

The first day the light was on:









Today, after some severe pruning, due to really fast growth of plants I don't want to grow that fast:









This light increases my light intensity by about 25% - the effect is very visible! I think this may be just the light intensity I want.


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## hoppycalif (Apr 7, 2005)

Two follow-ups: First, the major weakness I found with my first attempt at making an aquarium light using SMD LED tape strips was that the adhesive on the tapes didn't prevent the tapes from separating from the heatsink and sagging down. This time I did a much more thorough cleaning of the heatsink before attaching the tapes, and I used a bead of silicone sealant along each side of the tapes to reinforce the attachment. After about 3 weeks of use there are no sagging sections of the tapes on this light.

Second, I support the light with a drawer slide to make it easy to raise and lower it. Today I added a counterweight to make moving the light much easier - the counterweight is a 12 inch 1/2" NPT pipe with a cap on both ends, and filled with 1.25" long brads. Also, I reinforced the elbow joint on the support arm with a piece of aluminum angle attached across the top and back of the joint with 4 sheet metal screws. It is much stronger for that.


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## Hillbilly Homer (Sep 25, 2012)

Hows it holding up?


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## hoppycalif (Apr 7, 2005)

The light is working just great! Exactly as I wanted it to. The increased light intensity from what I had before, a Finnex Planted+, has made me have to get rid of all of my Sagittaria plants, which were a mix of dwarf and full sized species. They were an obnoxious weed with this light. The growth was so dense I was getting algae from lack of water circulation. And, they crowded out most of the other plants. So, it is now somewhat sparsely planted, but doing very well anyway.

I have it mounted on a drawer slide, vertical of course, so it is easy to lift up for access. I struggled with how to hold it in the lifted position, but finally just settled on a strip of wood as a prop. The counter weight I'm using is helpful in raising it, but not heavy enough to hold it in position. If I increase the weight so it will hold it, it will prevent it from staying in the down position. Some day when I get bored enough I will figure out a better way to hold it up.


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## DutchMuch (Apr 12, 2017)

Hoppy you know, from experience, that we all need an FTS so that you can prove to us its truly working lol

jk i'm just desperate for a FTS though


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## hoppycalif (Apr 7, 2005)

DutchMuch said:


> Hoppy you know, from experience, that we all need an FTS so that you can prove to us its truly working lol
> 
> jk i'm just desperate for a FTS though


The light hasn't come on yet, so I can't take a pic yet.


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## DutchMuch (Apr 12, 2017)

hoppycalif said:


> The light hasn't come on yet, so I can't take a pic yet.


OH
Sorry misread your post  My apologies :flame:

Shux thought you still had it on there, nvm


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## hoppycalif (Apr 7, 2005)

I just took this pic. I haven't started my weekly maintenance, pruning, cleaning, water change, re do one CO2 bottle, yet. But, the glass isn't that dirty yet.


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## DutchMuch (Apr 12, 2017)

looks nice hoppy, just let the three fastest growing plants take over the tank, if you did that it would look pretty af!
But lets be honest really anything is pretty if its underwater and its growing  

Good luck I'm following!


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## Hillbilly Homer (Sep 25, 2012)

:thumbsup: :thumbsup:


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## TropTrea (Jan 10, 2014)

For the tape problem instead of the tape use thermo epoxy. two part mix and is works fantastic.

For the heat if you about 12 square inches of surface per watt of led power it will get warm but not so hot to effect the water temp more than a degree in 10 hours. 

For intensity issues. You can get Meanwell adjustable Current drivers. I used 5 watt LED's that were 5 watts at 1,500ma and rougly 1 watt at 350 ma. By using the adjustable drivers you can set the intensity where you need it. Note on some of my reef tanks I was runnng par's over 200 at the substrate on 120 gallon tanks. (roughly using 150 watts of LED's,) 

Using the Cree Stars you would not believe the difference in light per watt difference than most commercial units using 1/4 watt to 1 watt LED's. But they use the smaller LED's for heat issues with the plastic cases on their fixtures.


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## hoppycalif (Apr 7, 2005)

TropTrea said:


> For the tape problem instead of the tape use thermo epoxy. two part mix and is works fantastic.


 My silicone sealant is working out very well, so far. One problem is that those SMD tapes you buy on line can have good or bad quality adhesive tape, even on the same roll.


> For the heat if you about 12 square inches of surface per watt of led power it will get warm but not so hot to effect the water temp more than a degree in 10 hours.


 Those tapes can function with no heatsink at all, probably with reduced life. I bought some closet lights which use those tapes, which are intended to be stuck on wood surfaces. I stuck them on aluminum bars and they work fine that way, except for the varying quality of the adhesive tape.


> For intensity issues. You can get Meanwell adjustable Current drivers.


The SMD tapes use 12 volt power supplies, and they have resistors in series with the pairs of LEDs, to control the current. Meanwell adjustable current drivers don't work on them at all. Meanwell drivers are for LEDs in series, so the same current goes through all of them. The tapes are LEDs wired in parallel, so the same voltage is applied to all of the LEDs.


> I used 5 watt LED's that were 5 watts at 1,500ma and rougly 1 watt at 350 ma. By using the adjustable drivers you can set the intensity where you need it. Note on some of my reef tanks I was runnng par's over 200 at the substrate on 120 gallon tanks. (roughly using 150 watts of LED's,)
> 
> Using the Cree Stars you would not believe the difference in light per watt difference than most commercial units using 1/4 watt to 1 watt LED's. But they use the smaller LED's for heat issues with the plastic cases on their fixtures.


 I have made several lights using the Cree star mounted LEDs, with Meanwell drivers. They do work very well, but it is an expensive way to make a light fixture, as well as requiring a lot more work mounting and wiring them. If you want high light, the Cree LEDs are the best choice, but the SMD LED tapes are an easy and effective way to get less than high light.


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## TropTrea (Jan 10, 2014)

hoppycalif said:


> I have made several lights using the Cree star mounted LEDs, with Meanwell drivers. They do work very well, but it is an expensive way to make a light fixture, as well as requiring a lot more work mounting and wiring them. If you want high light, the Cree LEDs are the best choice, but the SMD LED tapes are an easy and effective way to get less than high light.


I would not call them expensive compared with what they are getting for many of the better manufactured LED systems. But they do cost more than the SMD tapes as a starting price. When you crack the light intensity up they are much cheaper per lumnin or par than any of the older systems and as you have said they can be made much brighter.


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## TropTrea (Jan 10, 2014)

hoppycalif said:


> I have made several lights using the Cree star mounted LEDs, with Meanwell drivers. They do work very well, but it is an expensive way to make a light fixture, as well as requiring a lot more work mounting and wiring them. If you want high light, the Cree LEDs are the best choice, but the SMD LED tapes are an easy and effective way to get less than high light.


I would not call them expensive compared with what they are getting for many of the better manufactured LED systems. But they do cost more than the SMD tapes as a starting price. When you crack the light intensity up they are much cheaper per lumnin or par than any of the older systems and as you have said they can be made much brighter.


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## mistergreen (Mar 3, 2007)

You can probably increase the brightness by upping the amp. I'm not sure how many LEDs you have but one 5630 takes 0.15 amp, and 5050 takes 0.06 amp. Multiply that by your number of LEDs.


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## hoppycalif (Apr 7, 2005)

SMD tapes have current control resistors that keep you from adjusting the current. The LEDs are all in parallel, and they are designed to be powered with 12 VDC, whether you have 3 LEDs or 100 LEDs operating. You just need a power source that can provide the needed current, which means the needed power. The double width tape seems to need 24 VDC power. It should be possible to at least slightly adjust the current by adjusting the voltage, but I never tried that.


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## mistergreen (Mar 3, 2007)

I see. How do you determine the current power supply (current) depending on the length of the SMD strip?


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## hoppycalif (Apr 7, 2005)

The tapes I have purchased have a total current spec for the whole reel of tape. So, I just went by how many reels of tape I was going to use, and rounded up a bit. Most of the tapes have a dimmer that can be attached, but I never looked into that. It's pretty hard to have too much light with those tapes - too little is the usual problem.


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## mistergreen (Mar 3, 2007)

Did you get the waterproof strip or non-waterproof?

***
I did a little digging.
https://www.saving-star.com/smd-led-comparison/
Check out the 3030 or 2835(c). Same current as the 5730 aka 5630 but much better lumens. Oh, but the watts is higher too, meaning the voltage is higher.


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## hoppycalif (Apr 7, 2005)

Bad News! This LED light has been in use, 8 hours a day for between 7 and 8 months now. I'm in the process of downsizing my aquarium set-up, so I have emptied the tank, cleaned it up for sale, and to improve my chance of selling it, will include this light. First, I measured the PAR it is now producing, and got 25 PAR at the tank bottom, less than 30 PAR 2 inches above the bottom. So, the intensity dropped from around 50 PAR to about half that in less than 8 months!

SMD LED strips, at least the cheaper ones, are clearly not going to last very long in this application. This is the last time I will use them. Back to Cree LEDs for me! Pay more, get more.

Curiously, my Finnex Planted Plus light has spent that same 7+ months as a desk light, on about 12 hours a day. It, too, is much dimmer now. It uses SMD LED's also.


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## mistergreen (Mar 3, 2007)

Good to know. Do you know how much intensity the Cree LED in 8 months? 

I have some Cree LEDs but never measured when I set it up.


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## hoppycalif (Apr 7, 2005)

I don't know how fast the Cree LEDs lose their intensity. Being pretty gullible, I am assuming they are as good as their website says they are.


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