Thursday, September 24, 2009

Homebrew DC LED lamp

Spread the light: Actually, the funnel is just for looks. The LED lights up a pretty narrow area.

The hardware store where I get my weekly fix has started stocking 3w DC LED bulbs which emit "warm white" light, 3000 kelvin. This is astonishing stuff. Just a couple of years ago the best I could get were 1w LED bulbs with that eerie, sf-like bluish white light. It was either that, or solder together a whole bunch of small LEDs by myself, still emitting that creepy alien hue.
Below is the bulb, intricately engineered with an integrated heat sink, as it were. To the right is a "bulb socket", just a way to connect the bulb to wires.

Strangely, there are hardly any lamps around that this bulb would fit in. There are some hideous low volt-lamps for RVs, but they look like something you'd get free with a stick of gum.
I found a steel funnel, some heat shrink tubing, a cigarette lighter plug, wire and a switch which I think I got from some car shop, and strung it all together.

That picture on the wall, by the way, is from one of my former lives as a frame maker. I had a friend who was a budding artist who would come by after closing time with prints and I'd frame them for him, and get some of his works for my trouble. Much to my chagrin and surprise, he has become an art teacher instead of a fabulously famous artist. Those swaps would have made a good story.
Come to think of it, it's a nice story anyway.

Here's the lamp in action above my bed. The candle on the right seems just as strong, but that's just the camera talking. The light from the lamp is more than strong enough for reading.
It draws so little electricity it does not even register on my control panel, but if I turn on my 1 w LED table lamp too, they draw 0,6 amps put together.


Andy in Germany said...

Great tip, thanks. At first I thought it was for a bike, but then I recognised the bulb. They are pretty common here.

Hudsong said...

My biggest issue with LED lights is that super cool (I assume in the 6000K range) light that they all emit. Either that, or red! What selection. It's great to hear that 3000K are available now! Fantastic!

coastkid said...

that style of bulb is very common here in the UK now,we have 240 volts here (110 on building sites)
the bulbs here are 12 volt and are linked up so many to a transformer (240-12 volt), there often used in fitted kitchens and sometimes bathrooms,also garden lighting,good you have light to read with!!

Oldfool said...

You know that I have an unreasonable "thing" for lamps. I think I need "lamps anonymous".

Northmark said...

Andy, Coastkid: I made some 12v bike lights once, but used a 20 w halogen bulb that ended up melting the casing, made of pvc pipe connectors. Will probably end up trying to see how these LED bulbs will work on a mobile system.

Hudsong: Yes, LEDs have so far been better for weird stuff than for beauty.

Oldfool: I'm with you. For some reason, I always thought I had nothing in common with what I presumed were "Lamp people". But I still end up fooling around with them a lot.

Garrett said...

You could spread the light out some by using something as a diffuser. Maybe a sheet of paper or translucent plastic?

Northmark said...

Garrett: Good point! Maybe not necessary for this project, but I am making lights for my shop and this some diffusion might be just the thing.

Dinah said...

fascinating blog, I really love to read this, yes its true that Led Lights is very helpful in our life now adays, it brings different colors to our life..