SnowplowTortoise
Newly Enlightened
- Joined
- Feb 9, 2007
- Messages
- 106
Here's a little project I put together from spare parts. The host was an old Mag85 (4C) that I had already bored out for 26700 cells using a brake hone in a hand drill. That was fun for a while, but not terribly useful. So, off with it's head!
I cut it down to the size shown using a plain old woodworking miter saw. I removed all of the threads in the head using the same brake hone. The head is essentially press-fit onto the body, so it can be adjusted for focus with the proper application of force and some light swearing. I used a DHS heatsink and some SSC P4 I bought years ago for some other project. I didn't have any boost/buck drivers on hand, so I just put a 0.5 ohm 1 watt resister in the tail, along with a rocker switch I scavenged from an old cell phone charger (hence the non-functional status LED in the switch).
The wire that makes contact with the negative side of the battery is actually one of the legs of the resister and attaches to the switch. Another wire goes from the switch to the hole where the switch is mounted – it's squished in between the switch and bare aluminum hole, so there's pretty good contact.
Output is pretty standard for a single die light. I measured 0.40 volts across the resister, so I guess the LED is seeing roughly 800 ma. Overall, I'm pretty happy with this one. The switch is surprisingly easy to use and the overall size is just right for my hand. This one will definitely get more use than the Mag85 from whence it came.
I cut it down to the size shown using a plain old woodworking miter saw. I removed all of the threads in the head using the same brake hone. The head is essentially press-fit onto the body, so it can be adjusted for focus with the proper application of force and some light swearing. I used a DHS heatsink and some SSC P4 I bought years ago for some other project. I didn't have any boost/buck drivers on hand, so I just put a 0.5 ohm 1 watt resister in the tail, along with a rocker switch I scavenged from an old cell phone charger (hence the non-functional status LED in the switch).
The wire that makes contact with the negative side of the battery is actually one of the legs of the resister and attaches to the switch. Another wire goes from the switch to the hole where the switch is mounted – it's squished in between the switch and bare aluminum hole, so there's pretty good contact.
Output is pretty standard for a single die light. I measured 0.40 volts across the resister, so I guess the LED is seeing roughly 800 ma. Overall, I'm pretty happy with this one. The switch is surprisingly easy to use and the overall size is just right for my hand. This one will definitely get more use than the Mag85 from whence it came.
