Rack-mount Custom off-road lights

Hello everyone! Despite being new to the forum I have been reading threads here for several months to get information for this project and finally registered for some specific advice.

Background:
-I'm planning to build a set of Custom Off road lights to go on my Jeep's roof rack.
-I decided to build them myself primarily because many sold in stores go for over $300 each.
-Also, I needed a weekend project and wanted to learn something useful along the way.
-I have a background in engineering however my resources for this project are limited.

Limitations / hurdles:
-I would like to avoid drilling any holes in my new vehicle.
-I want anyone nearby to think the sun came up when the lights turn on.
-The lights are going to be semi-permanent and fixed to my roof rack, so they must be weather proof.
-I want the size to be compact. (Think standard PIAA rally light)
-Heat management (due to the LEDs I chose) - So far my biggest hurdle.

Solutions:
-To avoid drilling holes I am going to make the lights battery powered and remote controlled.
-For the lights I got greedy and purchased 4 *100W Bridgelux Vero 29 COBs (BXRC-50C10K0-L-04) (Data sheet: PDF)
--chosen for their 5000K CCT and 10,000 lumen capacity (They nominally run at 2.1A and 36.8V or 77.2W and provide 9,720 lumens each) (combined total 308.8W)
-To weather proof the lights I have decided to use 5 separate enclosures. One for each of my 4 lights, reflectors, and heat sinks with a 5th for the driver, battery, and control board.
-In every practical application I have seen these lights used in they are high bay lights (gymnasium lights) with large bulky heat sinks made to operate vertically.

Where the project stands (26 Nov 14):
-I have purchased several components and I have done a little testing with them.
-For the remote control I went with a cheap but sturdy (solid state) option of using a Raspberry pi to control a set of relays.
--I have a rudimentary phone app that connects over Wi-Fi to control the Pi's Serial header. This provides 5v to the low side of the relay thus energizing the relay and powering the LEDs.
*In the future I intend to finish a custom App that looks nice to replace the clunky and technical Pi remote app.
--There will be a weather proofed "Arm System" switch on outside of the control enclosure to boot up the Pi. (I have seen it take 10min or more to boot up)
-To drive the lights I am currently using a bench top 12v power supply and a cheap DC to DC constant current boost converter that maxes out at 15A input.
*future plans include a 24V battery to power the system (likey this one).
24V can provide a max power through the boost converter of 360W without melting it. I only intend to use about 310W
@ 309W the 11AH battery translates to ~1Hr of run time a peak stable power assuming I have all the lights on.
-I plan to use aluminum tubing for the housing with a clear Lexan cover for durability. I will be mounting the lights and reflectors using rubber high temp gaskets to get a weather proof seal.
-I am trying to decide the best way to cool these lights. For testing I have a few small aluminum heat sinks that do an moderate job of keeping the LEDs in the range of "burn you on contact" after just a few min of power.
--I have looked high and low for a good option here but heat management is what is holding up this project at the moment.
--the heat sinks designed for the Vero 29 LED tend to be very large (Mid sized examples) and/or will not work well horizontally (here is why).
--This has led me to entertain the idea of active cooling by affixing each chip to a water block and setting up a system that utilizes a small DC pump and a radiator to cool them. Despite adding a lot of complexity this option also allows me to save a lot of space at each light and relocate the cooling surface all while keeping the system closed loop (i.e. no PC fans exposed to the elements).

Anyway, that sums up my thoughts on the project.
Please offer up your suggestions and I'll be more than willing to answer any questions you might have.
When I get the time I'll try to add some pictures, but everything is just separate components right now. I added links to what I have in most cases.

I look forward to your suggestions and thanks in advance.
Very Respectfully,
MCSNWV

I didn't notice anything about being able to see when its dark in the above....is that part of your objectives, or is the one stated performance objective (It looking like daylight to bystanders...) pretty much it?

I ask because you call them off road lights for your jeep...which could mean you'll be doing slow speed trail crawling on night runs for example, in which case the light could be floody, but, hopefully, you're leading...because when the guy behind ME has roof flood lights on, it glares like crazy so I can't see, and the others in front of the lights can't see, etc.

If you are using them to supplement your high beams, you DON'T want light shining close up, you want it PROJECTED off into the distance to START lighting where your headlights were getting too dim.

Too much light close up stops down my pupils and KILLS my night vision...so adding too much light right in front LOOKS BRIGHT, but I can actually see LESS total distance.

On tighter trails, lighting to the sides and rear can be more useful, as straight ahead is typically the only direction you DO see with headlights. My JK's headlights' side vision sucks for example. Aiming the lights so you see the sides/not blind your buddies, can work too.


What sort of lighting would work for you? SO far, you have lumens...but, no focus.

Any pics????

What kind of offroad conditions? I live in a brushy & forested part of the Pacific Northwest. I tried Unity spotlights with landing light bulbs, mounted at the tops of the A pillars on my ex-Navy 1966 International. A light mounted over 7 feet off the ground gets hit by limbs. I think one of them survived. Roof rack lights are a liability for me. I may try some small camp/area lights on angled surfaces of the rack on our lifted Grand Cherokee, but nothing that sticks out to be snagged.

We've all seen roof lights on Baja racers, but they really only work for going fast in a straight line, in CLEAR conditions. Those modded spotlights (#4537 in right, #4522 in left) taught me that if there is the slightest smoke, dust, fog or snow in the air, high level lights will blind me. I get more use out of front mounted lights. Experience at the end of a day in Extended Buck Season, with a 3 point down well below the road, taught me that work lights atop the brush guard on the extended winch bumper are a good idea. For me, roof rack lights would be floods for crawling and maneuvering. That same International one-ton 4x4 received high level rear floods, as work lights and to supplement the sealed beams inside the rear bumper when backing up offroad.

I should note that high level eyeballs can be useful. I recall a trip from Marblemount to Newhalem in blowing, drifting, whiteout conditions. My wife had the Saab with good Cibie headlights and fogs. But in the truck, with my eyes being 7 feet up, I was better able to make use of my low beams and see any drifts. So I led.

Another consideration: With both the International and even with my spotlight equipped 2000 Crown Victoria, I found that light onto the hood could be distracting. The hood of the faded gray truck really lit up with a spotlight in use. Turning on a spotlight in the Crown Vic (H7680X HIR halogen sealed beam) wasn't bad in the dark green car (crappy driving light, but it could light up a straight stretch). However a dusting of snow or frost on the hood made it very annoying. Now that I think of it... I've owned two white Suburbans, 1993 and 1996, and the first one had the 5 "DOT" cab marker lights which were an option. Even those little amber lights threw a noticeable glow onto the hood. Back in the day, **** Cepek sold what appeared to be visors that mounted on the underside of rollbar and roof rack lights, in an attempt to block the downward light which would mess up the driver's night vision if it didn't outright blind him.

If you are set on roof rack lights, I suggest keeping them as low profile as possible and thinking in terms of area floods instead of driving lights. If they throw any light down onto your hood, they will only be useful when parked in camp.

Hamilton Felix said:

If you are set on roof rack lights, I suggest keeping them as low profile as possible and thinking in terms of area floods instead of driving lights. If they throw any light down onto your hood, they will only be useful when parked in camp.

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Upside-down fog lamps (carefully picked ones) can be put to good use in such an application. The top cutoff becomes a bottom cutoff to avoid the hood-reflection glare you describe.

I like that!