Preamble...
I had been thinking about buying a bright work light / camping light, something that I could plug into a 12V power outlet (cigarette lighter socket)-or direct connect to a car battery. Bright enough to use while doing repairs, as well as setting up camp / breaking down camp. Something which wouldn't drain the battery "too quickly".
The ones I had seen online, and previously owned are either very expensive, or used halogen type lamps/bulbs. The one I had previously owned was incredibly bright, but also used those halogen tube type bulbs, so although I don't remember the specifics, it was surely high wattage (?20-50Watts +).
My folks had bought a very nice desk lamp/reading lamp which used an LED bulb. Its 12V, with a power converter plug at the household wall socket. It is very bright and would work great for my idea! But, my Mom wouldn't have her evening reading lamp anymore if I took it apart to play with. Buy another one? Nah, too pricey (I think they said it was ~40-50$, maybe more).
Getting to the point...
I saw some LED bulbs in a Lowes store, and seemed to recall seeing someones post online about modifying them to use as either a bicycle light, or the exact same application I wanted.
The bulbs I saw are a size MR16, 20W equivelant, but only use 6W. They were $9.99, (half price or more of what I had previously seen online). -Half price I thought, worth playing with then...
How to mount it? That seemed to be the problem. Housings for those type bulbs seemed to be expensive, at least in my brief search. The bulb socket can found online for 1$ or even less.
I remembered seeing some underwater lights online at Harbort Freight which might work in my application (I also remembered seeing someone else modifying them on the internet). They cost $12 each, and my local Harbor Freight had some. The same store also had all kinds of 12V accessory cords. I bought an 8' coiled extension cord for a cigarette socket $8, and an accessory cord assortment which included aligator clips to a female 12V outlet 7$.
Cost : 10$ for bulb, 8$ for coiled cord w/male socket (with a fuse in it), 7$ for cord assortment.
I had to modify the MR16 bulb by cutting a few mm off of the heat sink, as the Harbor Freight underwater lights use the smaller MR11 type bulb. A dremmel type tool with a cutting wheel and wire brush did the job with ease.
anyways...here's the first one I made:
Top down image of modified MR16 bulb (I put some Yelllow Vinyl film on it):
Picture of the MR16 bulb before cutting down the heat sink ("Ecosmart" brand from Home Depot on the left, Sylvania from Lowes on the right). The "Ecosmart" seemed it would be easier to modify the heat sink, so that is the one I used.
My new work light clipped to an accessory bar I put on my bike rack:
Same:
Conclusions:
I really like it, and I think it's danged nifty!
I ran it for over an hour from household current to see how hot it would get, especially since I cut a portion of the heat sink off. It did get hot, but did not melt the housing. IMO completely enclosing this bulb would likely pose a fire hazard, so I chose not to modify the original lenses that came with underwater light.
I ran it for well over an hour from my Pathfinder rear seat accessory outlet, and had the stereo on / engine off.
I might think about installing some type of dimmer/switch directly into the cord. Not sure yet.
If I can, I'll take some night photos. NOt sure with the phone/camera deal...
Night photos-not so great...
My "Home made" light, next to HID fog lights:
My "Home made" light, HID's off:
