llile
1 kW
- Joined
- Dec 18, 2010
- Messages
- 457
Well, surveying the landscape for headlights, I see several options:
1. Many folks have had luck with Cree LED flashlights. This is a simple hack, and can also be rewired to a DC-DC converter and run off the traction battery. Several threads on this board, not going to review this idea as it has been explored and is viable. Not for me though. No side illumination, otherwise very doable.
2. Bike headlights. These generally suck, being made out of breakable plastic. I have returned three rather high-end ones because they blink on and off randomly. 120 lumens is typical. Not too bad as long as they work. waterproof. Hackable to a DC-DC converter. Has side illumination.
3. ebikes.ca's very professional, but very pricey headlamp. Great product, but out of my budget.
4. ebikes.ca's less priceyLots of LEDs (LOL) headlamp I already built one of these, not happy with it.
I will make no excuses as to why I am not hacking a ready-made commercial product like a flashlight. That's a great idea and not worth posting a me-too topic.
I am trying to make some headlights (because I can) with the following specs:
500-1000 lumens
durable metal case
side illumination
Matching rear red lights that blink and are super bright
CREE LEDs as light engines
Efficiency over 100 lumens per watt.
Cost under $75
The efficiency was science fiction 5 years ago, now you can get a Cree LED that approaches 300 lumens per watt easily for less than the price of a good breakfast.
Here is the plan:
Case will be an aluminum boxfrom Jameco. Durable, waterproof, hackable, functions as a heat sink, will bolt onto a steel bracket. Any internal electronics will be coated with something durable and waterproof after I get it all working. I may well pot the whole thing into epoxy after masking the optics, to make it indestructible. I am going to need these to blind the zombies when they come.
LEDs will be CREE LEDs on a star board These can be run at 330 lumens on a heat sink (aluminum case). 3 of them in series will run at about 9 V. Total lumens will be about 1000.
A similar red LED, mounted on the sides, will provide side lighting.
Optics can be bought from Jameco or Mouser.
I have already made a nice little successful build of this starboard LED and optic system for an undercabinet light in my kitchen. I used an off-the-shelf AC to DC LED driver power supply. red side lights will run at reduced current, probably two LEDs and a resistor, paralleled with the three brighter white LEDs. Maybe I'll post a schematic, nobody is going to decode that last sentence.
Star boards are really slick. Insulated, but good conductors of heat, they mount a high power LED to whatever you glue them onto. I used a small lenght of aluminum bar for a heat sink in my kitchen undercounter lights that worked very well. Easy to solder, they convert the surface mount LED to something any thumb-fingered guy with a soldering iron can handle.
Hey... If that little wall wart will run on DC, then I've got a ready-made way to run these puppies. Hmm - they make a 750mA model here , also some open frame LED drivers that might be set up for DC already. I'll check it and see if it works.
On the rear, I will also use LEDs, but they are red and must blink. About 15 years ago I integrated blinking LEDs into my bike helmet, using high brightness LEDs and a PIC microcontroller to blink them. This finally broke down about a year ago, but was bright enough to make the stopsigns a block ahead blink red in the reflection. This time I'll use an Ardweeny, just to save space, and drive the LEDs with a small transistor. I'll use a small series resistor on the red LEDs, or not. On the last blinky I just relied on the resistance of the transistor to limit current into the LEDs from 3 AA batteries. Due to the blink rate, I could put a huge pulse of current into the LEDs, yet not burn them out and not use much juice. The blinking helmet would run for months on a set of AAs. I might run this from straight 9 volts, or with an LED driver I haven't decided.
Switch? We don't need no stinking light switch. I am just going to wire them "on". Why not? They are going to use less juice than a cell phone. I might put a dimmer switch on them, in case I am riding at night on a bike trail rather than a street. Or not, you never know when you might need to blind the Zombies.
1. Many folks have had luck with Cree LED flashlights. This is a simple hack, and can also be rewired to a DC-DC converter and run off the traction battery. Several threads on this board, not going to review this idea as it has been explored and is viable. Not for me though. No side illumination, otherwise very doable.
2. Bike headlights. These generally suck, being made out of breakable plastic. I have returned three rather high-end ones because they blink on and off randomly. 120 lumens is typical. Not too bad as long as they work. waterproof. Hackable to a DC-DC converter. Has side illumination.
3. ebikes.ca's very professional, but very pricey headlamp. Great product, but out of my budget.
4. ebikes.ca's less priceyLots of LEDs (LOL) headlamp I already built one of these, not happy with it.
I will make no excuses as to why I am not hacking a ready-made commercial product like a flashlight. That's a great idea and not worth posting a me-too topic.
I am trying to make some headlights (because I can) with the following specs:
500-1000 lumens
durable metal case
side illumination
Matching rear red lights that blink and are super bright
CREE LEDs as light engines
Efficiency over 100 lumens per watt.
Cost under $75
The efficiency was science fiction 5 years ago, now you can get a Cree LED that approaches 300 lumens per watt easily for less than the price of a good breakfast.
Here is the plan:
Case will be an aluminum boxfrom Jameco. Durable, waterproof, hackable, functions as a heat sink, will bolt onto a steel bracket. Any internal electronics will be coated with something durable and waterproof after I get it all working. I may well pot the whole thing into epoxy after masking the optics, to make it indestructible. I am going to need these to blind the zombies when they come.
LEDs will be CREE LEDs on a star board These can be run at 330 lumens on a heat sink (aluminum case). 3 of them in series will run at about 9 V. Total lumens will be about 1000.
A similar red LED, mounted on the sides, will provide side lighting.
Optics can be bought from Jameco or Mouser.
I have already made a nice little successful build of this starboard LED and optic system for an undercabinet light in my kitchen. I used an off-the-shelf AC to DC LED driver power supply. red side lights will run at reduced current, probably two LEDs and a resistor, paralleled with the three brighter white LEDs. Maybe I'll post a schematic, nobody is going to decode that last sentence.
Star boards are really slick. Insulated, but good conductors of heat, they mount a high power LED to whatever you glue them onto. I used a small lenght of aluminum bar for a heat sink in my kitchen undercounter lights that worked very well. Easy to solder, they convert the surface mount LED to something any thumb-fingered guy with a soldering iron can handle.
Hey... If that little wall wart will run on DC, then I've got a ready-made way to run these puppies. Hmm - they make a 750mA model here , also some open frame LED drivers that might be set up for DC already. I'll check it and see if it works.
On the rear, I will also use LEDs, but they are red and must blink. About 15 years ago I integrated blinking LEDs into my bike helmet, using high brightness LEDs and a PIC microcontroller to blink them. This finally broke down about a year ago, but was bright enough to make the stopsigns a block ahead blink red in the reflection. This time I'll use an Ardweeny, just to save space, and drive the LEDs with a small transistor. I'll use a small series resistor on the red LEDs, or not. On the last blinky I just relied on the resistance of the transistor to limit current into the LEDs from 3 AA batteries. Due to the blink rate, I could put a huge pulse of current into the LEDs, yet not burn them out and not use much juice. The blinking helmet would run for months on a set of AAs. I might run this from straight 9 volts, or with an LED driver I haven't decided.
Switch? We don't need no stinking light switch. I am just going to wire them "on". Why not? They are going to use less juice than a cell phone. I might put a dimmer switch on them, in case I am riding at night on a bike trail rather than a street. Or not, you never know when you might need to blind the Zombies.
These babies run on 4.5V AAAs, so two of them run on 9 V. I have 9V on board! A quick wiring job put them in series, and voila! permanent lights. 
