DIY Cree LED bike light

[droo]

Chaps it seems as if May was a bad month for shipping out of HK.

 

Tech question: any one tried a triple MCE here locally and if so what driver did you use?

 

Haven't tried one yet, but it could be done with a maxflex. Run 2 x (4s + 2s), in other words 2 parallel branches of 6 chips in series, and set your drive current to 1200mA. You'll get 600mA per branch, not quite maximum but close enough.

 

 

 

You'll have to run a monster housing to get enough heatsink area to cool it properly though.

 

 

 

Post pics when you're done

[thysmeades]

hi jean,

I haven't tried a triple MCE (series)  but the recommendation from George would be a bflex using from a 14.4V battery pack. I actually asked him the same question.

regards

Thys

 

[thysmeades]

 

Chaps it seems as if May was a bad month for shipping out of HK.

 

Tech question: any one tried a triple MCE here locally and if so what driver did you use?

 

Haven't tried one yet' date=' but it could be done with a maxflex. Run 2 x (4s + 2s), in other words 2 parallel branches of 6 chips in series, and set your drive current to 1200mA. You'll get 600mA per branch, not quite maximum but close enough.

 

 

 

You'll have to run a monster housing to get enough heatsink area to cool it properly though.

 

 

 

Post pics when you're done [/quote']

 

hi droo, can i buzz you, I am confused about what you mentioned above. It would be great if you could explain to me about the 4s + 2s etc. is a triple not 3 lights?

 

regards

Thys

 

 

[RiderX]

Hi guys I've been thinking of using a parallel setup for my light as well (1xMCE 2xXPE, 2 of the MCE dies in serie with 1 XPE @ 700ma through each branch) and came to the conclusion that it might be a good idea to rather use 1 seperate driver for each branch.

 

The reason for this is that if one of the branches goes dead due to bad connection / busted component, then you suddenly now have 1400ma (in my case) through the other branch and then the other LEDS also goes BOOM!!!

 

[Brighter-Lights]

Johannes, is there no way of registering the parcel to ensure it gets here? sorry to hear that you are experienceing such issues. I know that you are so pumped to get the solo 580 out!!

 

All the above were registered. HK post won't play until the parcel is 'lost' for more than 2 months... they believe that it can still arrive within 2 months... but how can somthing leave HK on a certain date and never arrive or get scanned in SA for weeks? My past experiences were that the parcels get scanned in SA 3 to 7 days after 'leaving HK date'

 

I'll be using FEDEX or DHL from now on and my light prices obviously will go up...

Brighter-Lights2009-06-17 08:54:12

[thysmeades]

hi guys, can anybody tell me how to glue / solder emitters onto the heatsinks.

 

I am looking at joining an MCE bare emitter onto the star heat sink. Looks like a tricky job if it is indeed a solder job.

 

If it is solder, does on put a little bit of thermal paste on the bottom of the emmiter itself to ensure the heat is dissipated onto the star and then the heatsink?

 

[droo]

hi guys' date=' can anybody tell me how to glue / solder emitters onto the heatsinks.I am looking at joining an MCE bare emitter onto the star heat sink. Looks like a tricky job if it is indeed a solder job. If it is solder, does on put a little bit of thermal paste on the bottom of the emmiter itself to ensure the heat is dissipated onto the star and then the heatsink?

 

[/quote']

 

Thermal epoxy, sells as Arctic Alumina Adhesive, but only in the US of good old A. The heatsink slug on the back of the emitter needs to be electrically isolated from the leads, and AAA is an insulator, while thermal grease is not. The upshot of this is that you can't then use the contacts on the star board, you'll have to use the leads on the emitter.

 

 

 

In short - its a PITA. Next time, get the pre-mounted ones from cutter (link)

[Musashi]

Given the last few posts, this may be a bit off topic, but I need some advice from those who clearly know their stuff. 

What would happen if I put 18V through a {bflex driver + 3 x Q5 LED} setup?  Am I correct in saying I will fry the LED's?  Can I set up the driver to push out only 12V (i.e. reduce from 18V)?

[jean.roux]

Thysmeades

 

As always our good friend Google has provided a local agent for Artic silver thermal adhesive at a cost. Try www.cyberdyne.co.za they are in Roodepoort. You will be looking at R194.37 + courier charges for I think about 3grams. Eina!

[Brighter-Lights]

Solder gives a much better thermal path than Arctic Silver.

 

Google 'reflow soldering' - you can easily do it in your oven or on a stove plate. I use a butane torch and carefully heat the star. You don't have to tin the IC... just tin the contacts on the board...

 

Best would be solder paste...

 

[Carbon_Kooi]

Musashi just limit the current through the LED, then you will be fine. Don't know the specs of the driver, what voltage can it handle?

[droo]

Given the last few posts' date=' this may be a bit off topic, but I need some advice from those who clearly know their stuff.?

 

What would happen if I put 18V through a {bflex driver + 3 x Q5 LED} setup?? Am I correct in saying I will fry the LED's?? Can I set up the driver to push out only 12V (i.e. reduce from 18V)?

[/quote']

 

Nope. Wrong. RTFM, bflex is a buck driver, max input voltage 25v. It limits the current (the critical part) and automatically senses forward voltage for the number of emitters used. So what you're proposing is exactly what it's designed for.

 

 

 

Happy building, post a pic when you're done

[Musashi]

Awesome, thanks droo.

 

Now I just need to get those LED's from Hong Kong...

 

[tiger cycles]

Some may remember my post in Willehond's DIY light thread featuring a very nice heat sink.

I decided this heat sink deserves to be used in a killer light.
Something like a triple Cree XR-E Q5. Luxeon IIIs are old hat...

So I sourced some Cree LEDs and lenses from China:



I found that the lenses & LEDs were a good fit in 22mm brass end caps.
Heavy' date=' but good heat sink and easy to construct (lathe not required), so I built this monster:







Very bright light (much better than the Luxeons) and the beam distribution is not bad either; some useful spill light to light up the side of the trail.  (Beam shots to follow in another post).

So this experiment proved to be a success and I now had a bright light to use while figuring out how to turn the PC heat sink into a killer bike light.

[/quote']

 

 

Is this light in production yet ???

I would really like one

[tiger cycles]

Some may remember my post in Willehond's DIY light thread featuring a very nice heat sink.

I decided this heat sink deserves to be used in a killer light.
Something like a triple Cree XR-E Q5. Luxeon IIIs are old hat...

So I sourced some Cree LEDs and lenses from China:



I found that the lenses & LEDs were a good fit in 22mm brass end caps.
Heavy' date=' but good heat sink and easy to construct (lathe not required), so I built this monster:







Very bright light (much better than the Luxeons) and the beam distribution is not bad either; some useful spill light to light up the side of the trail.  (Beam shots to follow in another post).

So this experiment proved to be a success and I now had a bright light to use while figuring out how to turn the PC heat sink into a killer bike light.

[/quote']

 

 

Is this light in production yet ???

I would really like one

[mountain_lion]

 

 Is this light in production yet ???

I would really like one

 

Both lights are in daily use.

This is a DIY thread; I have shared my ideas.

Production is over to you...