Sunday, September 30, 2012

Battery Junk

Couldn't do any machining to the headlight housing this weekend, so I worked on some of the electronics.  This is a simple op-amp comparator functioning as a low voltage indicator to prevent me from over discharging the AA NiMH cells I will be using to power the headlight.  I easily yanked the circuit from the internet.  I may add additional circuitry to give a second level of battery charge, or use a different IC to give a full LED bridge displaying the power level.

Sunday, September 23, 2012

And so it continues....

Did some more work to the body.  Bored it to depth and ID for the LEDs and optics.

Put a big square hole in the back of the body for the LED driver.

Snug fit, gotta somehow squeeze 2 wire to pop through to the front side to feed the triple LED assembly.

Thursday, September 13, 2012

And so it begins....

Started on a housing for a new headlight.

Wednesday, September 5, 2012

Headlamp Re-Fixification

After-work riding has been getting cut short, much less daylight available, just wait until the clocks get set back, jeez.  So I suppose it is time to scrape together some "reliable" lighting.

I had 2 okay lights that both needed some work.

The light on the top is homemade that I copied from an Instructables.  That one fell apart a couple years ago, the epoxy securing the LEDs to the heatsink got pulled off by some tree branches. The light on bottom is a Cateye DoubleShot.  It has just lost a lot of its punch, and it always had kind of a crappy beam pattern.

After building the first light way back when, I purchased a bunch of other LEDs and things to build a second light and battery. but that never happened.  Soooooooo I had some lighting components "in stock."  The Cateye light housing and battery pack are both great, maybe I could jam some new LEDs and lenses in.

Start by gutting the headlamp.

The new LEDs, I had to file them down to get them to fit in the housing.
Also the new lenses, the hexagonal ones, compared the old lens between them.  The total stack height of LED/lens assembly was shorter than the original so I turned (2) 3mm aluminum pucks. That way the housing holds everything together nicely.

Soldered in some longer wire leads.  Two Luxeon III (now discontinued) in series, being driven at 700mA.

Screw it all together.

All the soldering was done with my dad's soldering gun.  This thing is the Cadillac of all soldering guns.  
140 Friggin Watts gets things soldered, QUICK!  

Here is the beam shot of the upgraded Cateye.  Not pleased with the light output, but the lenses are a nice improvement.  Maybe I will turn this into a generator headlight.  Or get some newer LEDs for it.

I also made a super janky repair to the homemade headlight, I just screwed the epoxy down to the heatsink to hold it all together.  Here is the beam shot for comparison:

I may be able to squeak a bit more light out of the Cateye Re-Hash. The LuxIII's that are in there are rated for 3W so they can handle almost 1500mA of current, the Cateye battery pack is rated at 700mA.
Now, on the other light, it is using a 1000mA driver which is driving the 4 LEDs at 500mA each, which according to the datasheets should be driven at 350mA.  So if I use battery pack A on headlamp B, and battery pack B on headlamp A, the homebrew light will be just about as bright as it is now, and the Cateye Re-Hash should be even brighter since i will be able to drive the 2 LEDs at 1000mA.
I made an adapter cable to use the cateye battery with the homebrew, and it works great.  It will have considerably longer battery life also bc it is a higher voltage battery pack.  I have yet to fashion an adapter to see if I can get more light out of the Cateye.   I'm thinking I should just get some new cable ends to make everything cross compatible.   Time will tell.