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More LED Talk


Buck's picture

By Buck - Posted on 12 March 2007

Well here we go again.
Daylight savings won't be around much longer so I'm thinking I will need to make up some lights soon to join you all on the night rides.
So I've been looking at putting some LED lights together. I'm sure I've got Rob's attention now Smiling

I was thinking of going a more simple route than Rob's setup. I was thinking just 2x 3W halogen replacement LED bulbs. Like this:
http://www.ledshoponline.com/high_power_mr16_led...

For power my friend has some old laptop batteries lying around. They are 3.7V 2000mah cells. And since he's a remote control helicopter flyer he's got all the charging gear for the lithium cells already. 3-4 cells in series should provide plenty of power for a fair few hours.

I would most likely just have 2 switches to switch between both on, both off and one on.

What do you guys think? Will it be bright enough? Any flaws in my assumptions?

Ben

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Stuart M's picture

I would not use this supplier again. I actually have this led and it does do a good job but it is not what it is claimed to be. This not the reason I wouldn't do this, I have one as a helmet mount and it does an adequate job. The problem is the guys attitude absolutely sucks. Completely forget about getting any help if you are unhappy with what you get, as I was initially. The beam is much wider than 10degrees. and what I have generally found is that the surrounding bush in the foreground lights up and you loose all distance vision.

You're welcome to borrow them for a ride to see for yourself, the unit is helmet mounted, as is the battery pack and with my helmet comes in at about 1kg total. Look at page 5 of the lighting gallery in the equipment photo gallery Like this:

3 Watt Helmet Mount LED light

PM me if you want, can't make this Wednesday though.

Stuart

FWIW yes it is probably the most simply way to get off road but there are now much much more efficient leds available.

Also its a 12V led, your going to need 3 batteries to get you close, I think it will be OK running it at 11.4v, assuming you get that much out of the 2nd hand batteries. If you do then the 2Ah batteries should give you close to 8 hr run time for 1 light.

Buck's picture

Hmmm good thing I asked then.
So what's a good LED to start with at the moment? Rob's Cree LED's? Bit more work soldering them together but shouldn't be too hard.

Unfortunately I can't test out lights anytime soon. I'll be in Melbourne for a week starting Wed and then soon after I have a 2 week Army course in QLD......damn. But when I get back I'd appreciate it very much if I could drop by on one of these night rides and see what each light can do.

Ben

Stuart M's picture

M16 Halogen and that is why you have looked at the above. If you do then this is an alternative http://www.cutter.com.au/proddetail.php?prod=cut651 Have a look at the triple towards the bottom of this page. Depending on which "bin" you choose each led could be brighter than 3w you have looked at and whilst you can't just plug it into a holder as you do with halogens, wiring this up would be alot easier than what Rob or I have done.

Don't forget though that these will need a driver between your power supply and the led, something your original link doesn't seem to need or use.

Stuart

Buck's picture

Hmmmm very interesting. Sure would make it easier than soldering 3 separate LEDs together. I don't actually have a halogen holder right now but I was going down that route as I thought it would have been the quickest.....two wires, a holder and battery.

But the Cree is looking good.

So I would just need a battery >13V or so. I'm thinking two RC Car packs will do. 7.2V each in series and available in capacities well over 3000mah.

Then one Buckpuck for power regulation.

And the 3 Cree's mounted on one circular board. Only downside to that would be I couldn't have different lenses for each LED but should be OK.

I'd just have a simple on off switch. No fancy circuits for me. I hear the Buckpuck is dimmable though so may just use that.

How does that sound?

Ben

Stuart M's picture

I used a bFlex from here http://www.taskled.com/ Like Cutter, this is guy is great to deal with and he has a fantastic product. Dimmable, lots of features and easy to program, once you have the switch wired properly.

If you want different lenses then you really need to look at something like this http://myfwyc.org/Timberlake/CreeLEDLight (thanks Tien)

Again this is an easy make and then possibilities re Leds and lenses are open.

Buck's picture

Wow thanks for all the info Stuart. The bFlex looks fantastic. All sorts of custom functions. The built in switch also makes for one less soldering job.

I hear that the Cree's run on 700ma? There's no issue with pumping 750ma through it is there as the bFlex does not seem to offer a 700ma setting.

Stuart M's picture

or atleast work out a way to activate it once the bFlex is installed in the housing, even then the switch needs to be soldered onto the board. I removed the supplied switch and wired a separate remote switch on the light housing.

Buck's picture

Alrighty
Thanks for all the info Stuart. Got a plan now.

Already ordered 2x 7.2V 3300mah Nimh packs. I was going to go down the lithium route and still may do if the laptop batteries turn out ok. Sure will save a lot of weight. We will see though.

I think I'm going to keep it simple and just get the 3 LEDs mounted on the one PCB with one triple optic on top. Thinking the 10 degree optic will be the go. The next step wider is 25 and that seems too wide to give any distance.

Still undecided on the bFlex or Buckpuck but both seem to do the job on paper.

As for mounting, I think I may mount directly onto a old Pentium 4 heatsink I have sitting around at home. Cut it down to size and that should give plenty of cooling.

Should be a fun project Smiling

Ben

shano's picture

Saw some LED lights on Ebay..shipping from Hongkong..
possible to get arrays of 21 or even 40 LEDs with variable settings..these things run on 3 AAA batteries..don't know how good they would be for night riding but at $10-15 thats bloody cheap.

Any ideas on how bright on lights like these might acutally be ?

I figure that the range would be pretty short..is it possible boost the rig with a bigger battery ???

The 21 led come with handlebar mount, the 40 led come in a headstrap thing which could be wrapped around your lid I guess...

Cheers

Shano

Buck's picture

I was in HK a month ago. And boy are those things cheap. Paying $10-$15 AUD would be considered getting ripped off compared to what the sell it over there for. Crazy
I bought a flashing red tail light for $12 HKD.....thats $2 AUD!

I saw lots of torches with dozens of LEDs on them. They were bright....probably like a Maglite kinda bright. But yeah anothing like Rob's floodlights!

Stuart M's picture

and referred to them in a post on last weeks night ride http://nobmob.com/node/1411

Maybe someone that was there can give an idea of what they were like. My old handle bar lights were a 19 led light and worked OK as a handlebar light, illuminating in front of the front tyre but certain would not have been bright enough as a stand alone light when doing anything quickly.

Stuart

Stuart M's picture

Have a look at these AyUp

You'll have to look at the Luxeon site as well to work out just how bright 2 x 3w luxeons are, pity they don't just tell us on their site, but still all this at that price will make other lighting companies stand up and maybe even drop their prices.

As for brightness, well they don't tell you do they. SO I went to the Luxeon site They claim 190 lumens per emitter but looking at the table the white ones are only 80 lumens each. Lets give them 100% efficiency and thats a total of 320 lumens, close but no cigar. They may of course over drive the leds which would make them brighter but hey how would you know which is why they should have light output on their site.

Enough rambling for now, mine's still brighter (hehe), for now atleast

Buck's picture

Well all the orders have been put in. Hopefully everything arrives by the end of this week so that I can play on the weekend with all the goodies.

I'll keep you guys informed on the progress Smiling

And sorry to Tien. Would have loved to take the batteries and driver off you but I jumped the gun and had ordered some batteries already.

Buck's picture

Well parts are slowly arriving. Can't wait

Have a look at the album here. Will put up more pics as parts arrive and construction starts

http://picasaweb.google.com/choi.ben/BikeLight

Stuart M's picture

special in there bargain bin http://www.renegadecycles.com.au/thisweek/bargai...

You would have to look at the nightrider site to see what they look like / features are but they seem heavily discounted.

Buck's picture

Well everything is here and slowly putting things together.

Pics are here:
http://picasaweb.google.com.au/choi.ben/BikeLight

I've glued the triple LED PCB onto a old computer heatsink. Lucky I mounted it on a large heatsink.....the light gets damn hot if running at 1000ma. I may drop it down back to 750ma to run it a bit cooler and get a bit more run time. I was getting temps close to 60 degrees celcius at 1000ma with no air movement over the heatsink.

Only minor gripe is that one of the LED lenses is not as perfectly formed as the other two and also gives off a slightly yellower light. Fortunately at full power the different colour tint is not noticeable.

I've managed to squeeze the bflex in between the lens and the PVC pipe you see in the pics. It only barely fits which I'm happy with so that I don't need to add the driver and switch on an external mount.

Just need to attach the power cable and glue everything down now. Also need to create a mount for my helmet.

Unfortunately won't be quite ready for this week before I leave. Can't wait to try it out for real though!

Ben

Buck's picture

Finally finished it after being away in QLD for the last 2 weeks. Can't wait to try it out on the trails!

Few final pics added:
http://picasaweb.google.com/choi.ben/BikeLight

Rob's picture

Hey Buck... looking good. A little on the large size, but if the weight isn't so bad then who cares, eh?

Sure you got it sealed up good against the rain, it's been wet here while you were away Eye-wink

Will be nice to see how it compares.

Cheers!

Buck's picture

Yeah I went a bit overkill with the heatsink. But it does allow me to run at the full 1000mA.
The casing will need to be sealed with silicone or something along those lines. I'll stick to riding on dry trails for now.

Would love to go on the night ride on Wed but unfortunately I'm in Melbourne this week! Damn. Never around long enough to get on the bike more regularly.

Well hope to see you all on the night rides ASAP!

Ben

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