Leds in Aluminum tubes with optics

[East Tn Bowman]

I was reading an old Thread by nightrider from 2006 and came upon an idea that i want to pursue at this point, there are several changes i would like to make to these but don't know much about the science behind this stuff yet, it blows my mind, mostly i play with engines and mechanical stuff and make a lot of custom stuff, I know i can make what nightrider has here but it just needs a little bit more refining, so here are the questions

1. When running the Cree xr-e bulbs, what is the maximum number of bulbs can you run off a single driver?

2. What are good drivers for running say 5 or 6 bulbs? At that point do you just get two drivers that are capable of driving 3 a piece?

3. Any one know of any other custom lights like these?

4. Would you stay with the 9 deg diffusers on the outsides of the spot optics ? for a hotter spot?

Here's nightriders site that was created from the project

http://bikeled.org/

My application will be running off a 12v marine battery instead of the battery pack that was used on the site.

Love the idea of the technology just would like some pointers/tips/different ideas

thanks

 

[TorchBoy]

Re: Leds in aluminium tubes with optics.

1. When running the Cree xr-e bulbs, what is the maximum number of bulbs can you run off a single driver?

2. What are good drivers for running say 5 or 6 bulbs? At that point do you just get two drivers that are capable of driving 3 a piece?
...
My application will be running off a 12v marine battery instead of the battery pack that was used on the site.

LEDs, not bulbs.

1. Apparently 72, but that's really four drivers in one. http://www.videofoundry.co.nz/ianman/laboratory/research/driverlist.php?order=leds_max.

2. http://www.videofoundry.co.nz/ianman/laboratory/research/driverlist.php?leds=6. Depends what your input voltage and driver type are.

For 12 V input you can get boost drivers that will run 6 LEDs but they're expensive.

 

[East Tn Bowman]

Alrighty, well lets refine these questions, What are some drivers that will work, not break the bank, and run several leds? like 3-4 Crees? What are different types of drivers i should look into?

 

[TorchBoy]

Does this help? http://www.videofoundry.co.nz/ianma...ck&v_in_min=10&v_in_max=14&leds=3&order=price

 

[East Tn Bowman]

Yes it does, Now to read it well enough to figure out what i need, definitely a start in the right direction thanks torchboy

 

[TorchBoy]

Here's a few more thoughts.

The highest efficacy Cree XR-E bin is R2, which jtr1962 tested as getting at least 252 lumens at 1 amp. (Another sample he tested gave 270 lumens.) After allowing for losses in optics, you might get about three quarters of that out the front (ie, 75% optic efficiency, but that's only a guess) so with four you could have about 750 lumens.

I think your marine battery might not have enough volts to run four XR-Es in series with a driver, but an alternative is the Cree XP-G which has a slightly lower Vf (forward voltage) so might work better. The XP-G goes up to R5 bin, so it makes more light for the same current. The XP-G is a very small LED, and is available on 10 mm square boards, with 10 mm square optics in a range of beam profiles, or with up to 7 on a single board, again with optics to suit.

jtr1962 tested a Cree XP-G R5 as delivering 351 lumens at 1 amp, so with just three of them you'd have about 790 lumens out the front (again allowing 75% for optic efficiency - that might be a bit generous). Also, with only three LEDs the Vf would be comfortably low enough to use any 12 V buck driver you liked (see link in post 4 above) without running out of volts.

Good heat sinking required, of course.

 

[East Tn Bowman]

What are my options on heat sinking those 3 together, i'm not sure what kind of tube i can find here that will allow the use of 10mm square lenses but I looked on the site where they were available and they could be put on 22mm boards, could i do that and add the 22mm square optics to it? since it fits inside a 1" aluminum tube, now the case maybe that the 10mm will fit in the 1/2 inch tube, just depends on the thickness of the tube, i'd have to hunt some of it up

 

[TorchBoy]

I wonder if 1/2 inch is the inside or outside measurement.

Cutter's web site is really bad but they're one of the very few places to get some items. On that XP-G page I linked click on the "XPG on MCPCB" link to get a list of the various boards on which the XP-G is available from them, along with links to optics. The drivers they list will very likely be much more expensive than ones you could use.

 

[East Tn Bowman]

1/2 inch is outside usually 1/16th thk, the 1" tube the guy that built originally is 1/16th which makes the 22mm optics a pretty close fit, and to heat sink it what all do you have to do, back it up thermally with aluminum? the led board and light and lens will be in the tube, i may build the driver storage a little differently than how nightrider did if you happend to look at the link, and that should be plenty of lumens to accomplish what i want i really appreciate the help

 

[TorchBoy]

I'd love to see photos of your finished housings. I thought nightrider's Copperhead "steampunk" design looks pretty cool.

I know someone here in NZ who gets a friend in Canada to send copper pipe end caps to him, since they're not available here. They work quite well.

 

[East Tn Bowman]

how is the heat sinking done? do they just set the copper cap on the board or do they attach it to the board? another idea is that coppers readily available and i could actually make the entire light housing out of it and acutally put it together without too much effort, and i will post pictures, its going to be an incredible amount of light out of such a small space

 

[TorchBoy]

He puts (for example) a Cree 8° optic on an XR-E star, then puts it all inside the end cap with a bit of thermal gloop to give a good heat path between the aluminium star and the copper end cap. It's quite a good fit for diameter, and the end cap provides both physical protection and heatsinking. Of course, he has a hole drilled in the end cap somewhere to run the wires through.

If he wants to get really serious he also mounts the end cap on a large heatsink.

 

[East Tn Bowman]

Sounds basic enough hmmm, have to take a set of calipers to home depot later and see what i can find i'm pretty sure i've got an idea to go on now, easiest way to show you a picture before its done is to just draw it in 3d, i'll post that up by later today or tomorrow

 

[TorchBoy]

Definitely about time for some pictures!

 

[East Tn Bowman]

Hotspot on boat, don't remember what settings the camera was on, but it was a dslr that was set to manual and all the pics were taken the same setting

60 meters to my back lot, no other lights on house, camera sittin at the same, you can see all the glowing orange High Pressure Sodium lights that are around the street

5 feet of water, using it as my application :tu:

here's what the housing looked like

i took an old computer heat sink, chopped and cut it down till i got a press fit in the square tubes, then i used the artic silver to put the diode bases in there, then added the optics, and i've had a lot of fun with this little thing, driven around my farm (100 acres) with out lights in the truck in the dark, and no problems, i've got a new design that allows more air to the heat sinks as well as not having to glue those tubes together which takes time to dry, what do you think?, this project has insured me that i have no desire to run a generator on my boat for fishing, haha, those guys that listen to that and put that kind of money into halogen and hps flood lights and build brackets for that stuff are a little out of my league, it works the way i want, only think i'm gonna change is probably use the oval spots in it to get a wider floodlovecpf