DIY Light Bar - 40 x XM-L2 on copper.

Assuming it even comes apart with out completely destroying it, youre going to have major problems with heat sinking (if youre going to drive it properly). :wink: You could put 100 lbs of copper in it, but it still lacks the surface area necessary to exchange the heat to the air.

My HID’s are 18,000 lumens and make a pair of BTU Shockers on turbo nearly disappear in the beam. I wanted something more and you probably will too.

Why not liquid cooled? Aluminum rectangular tubing with the ends welded shut, 1/4" NPT holes tapped for hose barbs at each end, a small 12v pump, and a transmission cooler...

disreguard

I can imagine doing something wrong and blowing up all those less in a second..at least that's would be a possible scenario if I had to do that..

Looking forward to the build.

http://www.fasttech.com/products/1617/10001275/1208514

You might want to consider these for reflectors, since space is tight. These should do almost as well as the C8.

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Great idea! I did consider liquid cooling but still needed a large aluminum surface to mount all the emitters and reflectors. When I found the right one on ebay, I pounced. According to the recommended total surface area requirements to exchange this amount of heat to air, I should be right in the ballpark of where I need to be. If not, the scoops and plenum should easily provide a 4x bump in cooling efficiency.

I already have an existing 2 x 100 watt HID setup on the front bumper (18,000 lumens) that provides 160 degrees of far reaching panorama. Even though the light housings were designed as cornering lights, the HID’s provide enough light they they completely overwhelm the stock high beams. The light bar is really a test platform for another array that Im building for a friends aircraft. The light bar will likely have a fairly decent spot beam straight ahead and provide more range than the cornering lights. During slow speed crawling, the cornering lights alone will be far more than enough and the light bar will likely be turned off.

Thanks OL. I actually ordered 16 of those last night for my friends aircraft. DX sells a 10 pack of 37mm lenses, so I ordered those as well. To bad Ric doesnt sell double sided AR in this size.

heatsink seems good, surfice area, is a tricky thing, it alone does not mean anything, same area might be more than enough as you drive, or not nearly enough when you stop, (no airflow).

i would not bother with liquid colling. KISS.

i would install a termostst on the bar, however, or two. small to220 t-stat, should let your driver, or you know temp is high, so either you manualy, or driver automaticly trims down current, i have done such temal control in my builds, works great. and it is not complicated. if your driver brighntess controled by current\ pot, you could include relay that will switch circuits, to “low mode”.

your bar seems just like heads that i build for my lights, just bigger. i would recomend ledil iris 38mm lens. i tried one made for mce, and it works just fine with xml. it is aslo attached by screws. also very important, you want lens\reflector that is screwed to the heatsink, not glued, you will have vibrations, that will comperimise glue, also i have no idea how you’ll be centering reflector you linked, and secure them. it will have to be very strong, vibration proof connection. also don’t try to press reflectors with your front glass. make sure they sit firm before you put cover on. or vibration will rattle them out of place.

It turns out that I already own one of the reflectors that I was thinking about using. It measures 41mm across and focuses well with XM-L2 and insulation gasket. Another piece of the puzzle down.


https://www.fasttech.com/p/1203500


https://www.fasttech.com/p/1182004

Thanks for your comments. The driver has thermal management and high voltage cut-off to protect itself but has no options to monitor and throttle for heat sink temps. Im probably going to mount the drivers in a remote location on their own heat sinks and put a cheap ebay digital monitor on the light bar to monitor it. Id probably need to ask the driver engineer how Id intergrate a to220 into the system, unless you’ve got some ideas for monitoring and management. Even a warning light would be very useful.

I like Ledil TIR optics but need as many forward lumens as possible, so Ive decided to go with reflectors. I think youre right about not letting the reflectors be retained by the lens because of impact rattling over bumps, although I might have one cut from quarts glass and use orings between the lens and the glass to cushion the clamping forces. I still havent decided. JB Weld epoxy between the mcpcb and spacer and again between the spacer and reflector will definitely retain that side or the reflector. I just might build a centering collar with 40 holes to retain the reflectors, but that would be such a pain to make and even more difficult to precisely align all the emitters on the sink. I think Ive seen gaskets with a lip, so if I could find the right size to fit the reflectors, they’d retain themselves. Another option might be to glue orings to the lip face on the reflector to dampen vibration. Any ideas?

There’s still much to consider.

if you want simple light to go on in your car to let you know the bar is too hot, you don’t need to do anythig with driver.

build simple circuit, where to220 tstat is a on off switch, it closes when it gets to its close\open temp. i usuasally install 70c t stats. even with copper stars like sinkpad.

if you have resistor in your driver which value you can change to change current. you can do autodimming,

i did similar in the light in this thread, post 21 has diargamm.

I just discovered that the driver has an option to monitor a thermal sensor on the light bar and ramp the current. Sorry, Ive been reading so many data sheets that I must have mixed this one up with another.

Data sheet link.

OH MAN, THIS IS EXCITING! Sounds crazy and like a job for the FlashPilot. Will be following this one.

I don't have anything useful to say other than I think thermal throttling (like your saying) is the way to go. The thought of being plugged into darkness while in a moving vehicle sounds very detrimental to the longevity of the emitters.

I agree, its probably best to let the driver manage the temps; especially since its capable of doing so. I could just envision getting distracted with something else (like getting stuck in a bog) and forgetting to dim the lights before they overheated.

Does anyone have any ideas for a decent removable roof mount? Then I can take it down when Im not off-road. This will also give it maximum range and great cooling while on the move. The front bumper is taken up with other lighting.

Those suction cups made for moving cabinets? There are many types made for holding cameras, cell phones and gps too, but those typically cost a lot more.

Self-tapping sheet metal screws? :D

Well, that's how it's done down here in Mis'ippi...

not sure if u posted but where are u wanting to mount this ? and are u looking at not drilling holes ?

Yepper, that an weldin em to the headache rack or the pusher par.

Whelp, ya’alls aint gots what umma tellin ya! I needs to stick the daing thing tuh the roof sos it aint stuck there all permanent-like, and I aint ganna be boring no holes in muh rig neither, daing ya! :smiley: