[Cameron] decided to give his twenty-year-old headlamp a makeover. He uses it when he’s out for a run and wanted to have more light to see where he’s going, as well as a red tail light on the back. The stock design uses an incandescent bulb on the front of the head band, and a battery pack on the back. He managed to convert the device to output 700 lumens without major changes to the form factor of the unit.

The first change he decided on is to use a Cree XLamp which provides the 700 lumens of light by drawing about 9.5 Watts of power. Obviously the original battery pack isn’t going to do well under that kind of load, so he also sourced a 5000 mAh Lithium battery. A bit of circuit design and PCB layout gives him two driver chips for the four-element LED module, a charging circuit for the battery, and an ATtiny13 to drive the head lamp and flash the red LED tail light. See the blinky goodness in the video after the break.

That’s a lot of light, but we wonder if he experiences a warm forehead from the heat sink used to keep that LED package cool? Read the rest of this entry »

[Brainiac27] isn’t going to let the absence of sun prevent him from biking. He has no trouble lighting his path with this 1300 Lumen bike light he built.

The light source is a 3-up star by Cree. It puts off a lot of light, but also generates quite a bit of heat which is the reason for that large heat sink. It is meant to be used with a CPU but works well for this purpose thanks to the adhesive thermal paste used to unite the two parts.

The mounting bracket is a custom job, bent from 1″ by 1/8″ aluminum bar. [Brainiac27] had some issues with length the first time he tried making it. For his second attempt he started with an overly long piece, made the bends from the center out, and only made cuts once the bends were all completed. The bracket makes it easy to mount to his bike, with the battery stored in a bike bottle and a remote switch (with attaches to the jack you can see on the project box above) hidden underneath one of the brake hoods.

The intensity of this light nearly doubles one of our other favorites.

[Tom] wanted to try his hand at high-speed photography and needed some equipment to get things rolling. Not wanting to spend a ton of money on a lighting rig or trigger mechanism, he decided to build his own. In a three part series on his blog, he details the construction and testing of his high-speed setup along with the improvements and lessons learned along the way.

His adventures started out with a small off-brand Cree LED clone and an ATiny15L that was collecting dust in his workshop. He built a simple circuit that would trigger the LED to light his subject, which in [Tom’s] case was a bowl of milk. Rather than using a motion or sound trigger, he opted to mount a small piezo to the bottom bowl, firing the LED any time a droplet hits the bowl’s surface.

The pictures he took were decent, but he knew he could get better results. He purchased a new, more powerful Cree LED, and wrote a small terminal program that allows him to tweak his flash parameters using his laptop. The results he gets now are far better – in fact, he has a whole gallery of pictures you can check out.

If you want to delve into high-speed photography as well, all of the schematics and code can be found on his blog.

Sometimes, sitting in a windowless office can drive you crazy. Adding a little bit of life and color can really help. [Gripen40k] did this by building a biosphere. He didn’t have any windows though, so he made an LED light on a PIC based timer. What is interesting is what he did with a thermistor. The Cree LED bulb that he salvaged was going to be submerged in the water, so he had to do some workarounds to keep from over heating the biosphere. Read the project log for more details.

[PodeCoet] sent in this mod he did to a Spider Fire flashlight. These things are unbelievably bright, they use Cree LEDs that are so intense, they can ignite paper. [PodeCoet] notes that they run on fairly expensive batteries. Instead of buying some rechargeable ones, he decided to customize and hack his torch. He added a custom charging circuit and a Lilon battery as well as a boost-converter circuit and a status LED.  We like the idea of having a rechargeable lamp, but he has lost his water proofing. If anything, you should go there to see his nicely done smd charger pcb as well as the pictures of his test run, burning some paper.

As some people have pointed out in the comments, this flashlight could not have started that fire. This one could though.