Rebuilding a suspect import led cause.....

Cause I can, and want to. But before I waste the $ I want to know that I can so I am going for a two CREE3070 DIY units first, then Ill have the lighting quality I want, Quantity will come with the conversion. The concept of this post is to ask questions and perhaps share a little accumulated knowledge (emphasis on little).

So heat is an enemy because it means a loss of efficiency so what can you do? you can get charts n stuff to tell you about pastes, epoxies, films, heat transfer but regardless of which one you pick and which heatsink you pick one constant is the flatter the surface the better the transfer. The attached picks show me flatting a heatsink using a piece of glass, valve lapping compound, wet dry sandpaper. If you can flatten a woodworking chisel this is the same thing. Human hands are so precise but the machines are so fast this took me a few hours.

The question I really want to ask is how flat is the back of the LED? I have mine but no way will I handle them like this though....

1) Check for flatness with a flat blade or straightedge (pic 7 shows gaps pic 8 is my best fair attempt at a comparison pic of the one I flattened). Place piece of glass on a flat solid surface so it dont rock and shit, place dabs of lapping compound on the heatsink and glass if the heatsink is anodized you spent more money on it so I'd pause real long before deciding to do this - use light even pressure in a forward and back motion as you slowly ratchet across to the left then back to the right (how far depends on how much glass and how much paste you have). Do this cycle 3 time then rotate the heatsink 90 degrees and repeat the cycle 3 times. This is so you take an even amount of material off any high spots. Repeat this for about 20-30 minutes. wipe the compound off (its messy so dont get it in the fins).

Is it flat yet? No. don't even check. How will I know when it's flat? Mark the bottom with a sharpie swiping left and right across it and repeat step 1 until you see no marks left pics 1-4 show the progression then I marked the piece again 90 deg to previous markings and repeated step 1 again.

2) get wet dry sand paper 400, 800, 1500 (go as far as you want but ager 1500 i just used a little mothers to clean up and film and seal the surface) and use wd40 with the sandpaper on the same glass (use a different section though as the one you used for the lapping compound is now uneven.

Clean up and your done.

Now my questions-

1) Can a 42V 1.5@ power supply run the CXA 3070 (Vf 36-42 from what I understand) and a 5v cooling fan if they are hooked in series without adverse impact on the LED array?
2) For the rebuild I am considering smaller led Arrays and pulling 1 of the 4 power supplies out of the Roleadro and using them for far red/IR and UV supplements, however I am having trouble finding what LED arrays emit those non-visible light spectra that are compatible with the application.
Roleadro power supplies are 28-36V @ 1.2amps. with the other 3 I plan to power CXB3070s with as Vf is 36V as opposed to the 38.5 of the CXA.

Hope you enjoyed the read and best regards

So, between credit card fraud and taxes I finally had some time today to sit down and take stock of what I have on hand to complete this project. Pictured in the mess of DIY Light 1 is most of the pieces and small parts, connectors and stuff. Also picked up another heatsink for passive testing (Look real close and you'll see the thermocouple temperature measurement thingy). Dont hahve long so pics are heatsinks sticking together with just wd 40 or water they are flat. Ratcheting motion described above when flattening is represented by the consistant angled line pattern. If the thing is sticking real good move to the next finer sandpaper and look for any shiny spots if so go back to the rougher grit. You should see a nice even reflection.

Woo Hoooo 35 minutes into first test run and COB temp on the passive heatsink is at 114 F still climbing. Running 2 CXA3070 in parallel off the OWA-60U-42 from meanwell.

1 hour and its stabilizing at 127 ish. with ambient temp of about 60F

OK so this thread of thought that apparently is not interesting enough for anyone to stumble on or at least if they have are just uninclined to comment... And I may be headed in an entirely different direction than I thought....

After doing the temp testing last night and burying my head in the various led threads there is so much more fun to be had with the parts in this Roleadro light than I originally thought. There are a few paths one could take here, if you have already made the mistake of buying this light:

1) Suck-It! just finish it out and make changes to the next run.
2) Trash It go put your wallet to work and keep on with all that goes choosing in favor of crappy mass production consumerism.
3) Rebuild it for whatever usefullness you can get out of it.

I've learned a hell of a lot in a very short amount of time thanks to the posts of others on RIU I'm not even gonna try to list them all.

The basic plan for the Roleadro is to put 2 CREE CXB3070's in it and a thermocouple on each of the cooling fans so they don't run unnecessarily. Then just keep the 2 extra power supplies in reserve for if/when the ones in use fail. This should be pretty economical but I'll keep track of what I can here so anyone who stumbles over here can have some info to base their decision on..

Up to an hour and a half on Temperature test #2 and LED case temp is 192F, on the passive heatsink used in the previous test, only this time I'm only running 1 off the QWA-60U. I did turn a 12V cooling fan on for about 30 seconds 30 minutes into the test and temp dropped to 147F...

I'd never heard of Roleadro. http://www.amazon.com/Roleadro-Grow-Light-Spectrum-Flowering/dp/B013QLEYTW

I recently took apart an old-school Procyon 100 but didn't see any way of salvaging it for a decent COB build.

sanjuan said:

I recently took apart an old-school Procyon 100 but didn't see any way of salvaging it for a decent COB build.

Click to expand...

You opened the box, now think outside it!! What still works and what do you need?

Homegrown Lights spent a lot of money for custom aluminum extrusions but the only thing worth reusing is a generic heatsink. I've got plenty of that from heatsinkusa.com. And it's not a box:

This thing does OK for veg (450nm + 630nm) but it is a heater, uncomfortable to hold your hand on the heatsink.

The LED panel is too recessed for a COB; I'd want to include side reflectors.

I see what you mean, the one think I am thinking of is if these are CREE XLamps come in many different colors including white and various different white balances. So if all the same benifits of underdriving the LED are the same as for the other led arrays you might be able to make it run cooler by getting leds rated for a higher amperage. The catch is to find them in the same configuration as what you have so they are direct replacements, then its just a matter of replacing what about a 100 of them?