creyc
Enlightened
After about 4 years of being "lost", I found my Surefire L4 tucked away in a pack I never thought to look through. This was my first foray into high quality flashlights and served me well until I misplaced it. After popping in a fresh set of CR123s, my first impression is WOW LED technology changed in the past few years! The light from the L4 looks quite pale and green, and with a single high mode of about an hour of runtime on expensive lithium primaries, I no longer have much use for this setup. I decided to have a go at making it more useful to me.
I started by replacing the LuxV with a more modern emitter. I went with a nice neutral-warm 4000K Cree XM-L. It took a bit of shoehorning and creative use of spacers but I managed to get it close to the right position, and no amount of banging, slamming and throwing it around (and not lightly!) has been able to shift the LED out of alignment. :devil:
Next was the issue of the battery situation. I don't have any 17670's on hand, and wanted a little more flexibility than running a unique size like that. I was also looking for more runtime with a tradeoff in output. I've got plenty of very bright lights, but the idea of a Malkoff M61LL as an emergency type light has always interested me. I took a look at the boost driver and made a few modifications to reduce the output to about 50 lumens. It runs on everything from a single CR123 (although much dimmer) to two 16340's or RCR123s. I still have to test the runtime but from a few quick tail cap measurements I think it's going to be a longgg time.
The beam is smooth and artifact free, with a slightly tighter hotspot than factory and a wide, very even useable fill. Actually the beam is quite similar to my Zebralight SC52 in terms of angle and fill, but with a noticeably tighter hotspot. This helps offset the reduction in output.
I took a few beam shots for comparison: left SC52w on M1, middle Surefire L4 w/ 4000K XM-L, right HDS high-CRI on my preset B 'general purpose' level.
Overall this is a specialty light now for sure, but I think it will do great as a glovebox light or an emergency long-life low output light. It's a light I could hand anyone, without instructions, and it will serve them hours and hours of very useable output. It's kind of amazing just how useful 50 lumens is for general navigating or looking behind the TV or what not. Once I nail down the runtime I'll be sure to update this thread. Right now it's out on the bench power supply for a continuous 8.4V hot-off-the-charger-simulation torture test for the next 24 hours. I'm sure it will do fine.
I started by replacing the LuxV with a more modern emitter. I went with a nice neutral-warm 4000K Cree XM-L. It took a bit of shoehorning and creative use of spacers but I managed to get it close to the right position, and no amount of banging, slamming and throwing it around (and not lightly!) has been able to shift the LED out of alignment. :devil:
Next was the issue of the battery situation. I don't have any 17670's on hand, and wanted a little more flexibility than running a unique size like that. I was also looking for more runtime with a tradeoff in output. I've got plenty of very bright lights, but the idea of a Malkoff M61LL as an emergency type light has always interested me. I took a look at the boost driver and made a few modifications to reduce the output to about 50 lumens. It runs on everything from a single CR123 (although much dimmer) to two 16340's or RCR123s. I still have to test the runtime but from a few quick tail cap measurements I think it's going to be a longgg time.
The beam is smooth and artifact free, with a slightly tighter hotspot than factory and a wide, very even useable fill. Actually the beam is quite similar to my Zebralight SC52 in terms of angle and fill, but with a noticeably tighter hotspot. This helps offset the reduction in output.
I took a few beam shots for comparison: left SC52w on M1, middle Surefire L4 w/ 4000K XM-L, right HDS high-CRI on my preset B 'general purpose' level.
Overall this is a specialty light now for sure, but I think it will do great as a glovebox light or an emergency long-life low output light. It's a light I could hand anyone, without instructions, and it will serve them hours and hours of very useable output. It's kind of amazing just how useful 50 lumens is for general navigating or looking behind the TV or what not. Once I nail down the runtime I'll be sure to update this thread. Right now it's out on the bench power supply for a continuous 8.4V hot-off-the-charger-simulation torture test for the next 24 hours. I'm sure it will do fine.
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