DIY TriLux3 Li-ion Bikelight

[KonradC]

Wotcha

Having come accross this fantastic website last year, I began experimenting with LED lights, after making a number of halogen bikelights. This is the result of my experimentation:



The casing is built from four 22mm copper end-caps bonded together, three housing the 'U' Bin 3W stars and the fourth to hold a Fatman driver. This is sealed using the top from a bottle of soy sauce. I've added a potentiometer to the fatman to provide stepless flicker-free control of brightness from a decent low beam with 80Hrs runtime to full power (300 lumens +) for 3.5 hours.




The light is powered from a 7.2V 2400maH Li-Ion battery that sits in an inner-tube sarcophagus held in a 5mm neoprene bag. This straps to the frame using a velcro cinch strap



The whole lot weighs 240gms and I eventually hope to add some better connectors to improve watertightness and shorten the potentiometer shaft.

It casts a good spread of light, illuminating the roads and signs for at least 50m. I found the carclo 6deg optics to produce a flood beam but I might investigate replacing one of the lens with a tighter beam lense, possibly a conventional reflector to illuminate the road surface a bit more. Overall, there is plenty of light to ride at >20mph and the lack of weight of the system is a bonus.

[Long John]

Hello KonradC

Welcome at CPF

Wowww, that's a nice start and a great bikelight

Best regards

____
Tom

[ktronik]

ktronik

[DUQ]

Man those are awsome. Nice job! Could you elaborate on the colimator's please.

[jar3ds]

WOW! Awesome!

[Icarus]

Very nice mod! ... ...

[nemul]

thats cool!

[Led_Blind]

Very nice build!

[roguesw]

that is a nice bike light
can i ask how do you wire up the 3 leds to the driver and how do you wire up a potentiometer to the light
and finally, how do you work out which is positive and negative on those connectors you are using
thanks very much
Cheers
Des

[greenLED]

Originally Posted by roguesw

that is a nice bike light
can i ask how do you wire up the 3 leds to the driver and how do you wire up a potentiometer to the light
and finally, how do you work out which is positive and negative on those connectors you are using
thanks very much
Cheers
Des

Yeah, tell us the steps you followed to build your light, please?

Nice job! I love it when people post creative builds like this.

[bombelman]

Very nice and very clean !!

What optices were used ?

[Timson]

Very nice..

Great idea on using the copper end-caps.

You've inspired me to do a similar build myself....Might even steal the end cap idea - If I can find any of a suitable size to accomodate what I want to do.

Where did you get the handlebar mount?


Tim.

[andrewwynn]

"number five is alive" (maybe more like number seven-point-five).. very cute, very practical.

[greenLED]

I was thinking... Could you replace one of those LuxIII's with a LuxV and drive all of them off the same board and battery? Or would you need 2 separate boards and independent batteries. Something like that would be a killer bike light.

[gearfreak]

Nice work and really clean profile, just wondering what range potentiometer did you use?

Originally Posted by Timson

Where did you get the handlebar mount?

Looks like a vistalite nightstick lamp mount to me

[greenLED]

Originally Posted by gearfreak

Looks like a vistalite nightstick lamp mount to me

Yup, looks like it.

[roguesw]

greenled, i was thinking the same thing
i am in the process of designing a panel light to house that combination, several Lux IIIs and a Lux V, but i dont know if i need a separate board and if i can run them both from the same power supply
so far , no one has answered the question i posted yet
the search continues

Originally Posted by greenLED

I was thinking... Could you replace one of those LuxIII's with a LuxV and drive all of them off the same board and battery? Or would you need 2 separate boards and independent batteries. Something like that would be a killer bike light.

[KonradC]

wow, thanks for all the kind complements and interest guys.
I'll try and answer your questions:

DUQ & bombelman: I'm using Carclo's 6deg colimators as they were kind enough to provide me with some free samples last year. The colimators sit in their little 'baskets' this slides over each led. Since I was not keen on permanantly bonding these in place, I wrapped electrical tape around the outside of the 'baskets' to achieve a friction fit in the copper end caps. It sounds dodgy but has been fine for the past month.

roguesw: The three front endcaps have aligned holes drilled through each to allow wires to pass through to the leds internally. These were marked and drilled prior to bonding to ensure accuracy. Short sections of plastic tubing were then located in the holes to prevent the adhesive from blocking the holes. Further holes are drilled through to the rear end cap to connect the leds to the Fatman driver board. The potentiometer is wired into the driver board as detailed in the instructions on www.taskled.com. As I couldnt find a small enough switching 47k log pot and had to settle for an unswitched pot, the light is always on untill the battery is disconnected. In practice, this is not a problem as it is easy to drop to the lowest power level which barely tickles the battery.

I wired up the batteries myself as these came without connectors from batteryspace. I believe I wired both the battery and charger as centre positive pin but this is purely a personal preference and either polarity would have been valid in this application.

One of the 3W leds could be directly replaced with a 5W led as I'm driving the leds at a max of 700ma, but this would reduce runtime. Prior to this light, I ran a single 5W led using a similar copper endcap layout but was unimpressed with the beam produced using the 6deg carclo optic. From reading this forum, it turns out the 5W led is more difficult to focus than 3W.

Gearfreak: Good sleuthing, it is a vistalite bracket. I got it a couple of years ago from www.chainreactioncycles.com for my old diy halogen light, however, they no longer stock these brackets.

Timson: I've found caps in 15 22 and 28mm sizes from most plumbers merchants. Usually around 25p each. Don't go to B&Q as they are a quid a pop and I've found these to be of poor quality compared to those sourced from a plumbers.

hope that helps

Konrad

[greenLED]

Originally Posted by KonradC

One of the 3W leds could be directly replaced with a 5W led as I'm driving the leds at a max of 700ma, but this would reduce runtime.

Just to verify I'm understanding correctly: you had 2xLuxIII and 1xLuxV wired to the same converter board?


Thanks for sharing the details on the wiring/construction!

[KonradC]

Originally Posted by greenLED

Just to verify I'm understanding correctly: you had 2xLuxIII and 1xLuxV wired to the same converter board?

No, I havn't tried them together personally, but according to the spec-sheet it is possible to connect both 2xLuxIII in series with a 1xLuxV and drive them all using a single Fatman. This would, however, draw more power from the battery to drive the increased forward voltage of the combined LED string.

[Bandgap]

Nice and neat.

Did you have to flatten the rear inside surface of the end caps to take the Luxeons, or was it flat enough for heat flow as bought?

Steve

[KonradC]

Good point about flattening the endcaps, Bandgap. I forgot to mention this in the build details above. The raw endcaps are very rounded, preventing a good contact between the led heatsink and the copper surface. To get around this, I inserted a short section of aluminium bar that had a machined end into each endcap and compressed this in a vice. As copper is very ductile, only moderate pressure was necessary to get a flat end. This also helped when bonding the front and rear endcaps together as the original rounded ends would have been difficult to bond strongly and align accurately.

[nightrider]

Nice job KonradC!
I've built a couple of bike lights and know how fun and rewarding it is. I've seen someone else on MTBReview.com use the copper cap method and thought about it myself. It looks hard to beat for size and simplicity. Your workmanship and design looks great!

[sfCyclotourist]

&^!@#&^!@%# I spent a good couple of hours last week rummaging around in two different hardware stores looking for something to make a LED bike-light housing with. I repeatedly looked at these same copper-pipe caps and couldn't come up with a design that made sense. It never occurred to me to bond (or solder) two of them back-to-back like this. Nice! What brand of soy sauce did the plastic cap come from?

[RustyKnee]

Originally Posted by sfCyclotourist

&^!@#&^!@%# I spent a good couple of hours last week rummaging around in two different hardware stores looking for something to make a LED bike-light housing with. I repeatedly looked at these same copper-pipe caps and couldn't come up with a design that made sense. It never occurred to me to bond (or solder) two of them back-to-back like this. Nice! What brand of soy sauce did the plastic cap come from?

glad i found this thead. I think I saw this ligh on singetrackworld orignally?

RS have similar ends here

not sure if they are deep enough yet though....might order a couple to measure

This kight is lush....I want to build a seoul version

Stu

[Krit]

Very Very good Job...

[KonradC]

Yeah, I posted it on singletrack after reading through those killer long threads. Cheers, I also want to upgrade the LED's now, three cree's or seoul's would be a major upgrade in brightness, but I'm waiting for Taskled's new MaxFlex before doing so that I can get rid of the potentiometer.

Stu, I'm curious about connectors you linked to at RS, the link didn't work for me, could you repost it?

[RustyKnee]

Originally Posted by KonradC

Yeah, I posted it on singletrack after reading through those killer long threads. Cheers, I also want to upgrade the LED's now, three cree's or seoul's would be a major upgrade in brightness, but I'm waiting for Taskled's new MaxFlex before doing so that I can get rid of the potentiometer.

Stu, I'm curious about connectors you linked to at RS, the link didn't work for me, could you repost it?

Hi

The link was for the copper end caps similar to what you used. I didn't realise RS links are only valid for a give session. The RS stock number is 797-928 . They look a bit squarer that the ones you used. they aren't deep enough as they are either. I need ot get a bit of 22mm 0.9mm wall pipe to see if my 20mm reflecotrs will fit inside. If so, I will extend the cap with a short length of pipe,

Where did you get your pipe ends from?

Stu

[tvman]

real cool - "You have some really nice headlights" - I once said that to a woman but the reaction was quite different.

[270winchester]

nice light.

what happened to your steertube cap?