Ingredients: one cheap generic plastic 2C light, one 700 mA KPR118 bulb ($1.29 from RS), three Yuntong CR123's, a sliced down TP roll wrapped with one of those cardboard coffee cup wrappers, taped together with packing tape. Other similar mods have used rubber hose, PVC pipe, or nicely machined nylon sleeves, but I never felt like scouting the hardware store for that stuff, so I did it with free materials that were on hand.
The cardboard stuff is pretty sloppy. It's hard to get it to wrap smoothly, especially the cup holders, which had pre-formed creases. But it does the job. Just to reduce the slop a bit, instead of leaving the three 123 cells loose, I made a "battery stick" by taping the cells with a lengthwise piece of packing tape. Swapped out the PR4 bulb for the KPR118 and viola.
Output is only slightly less than my Streamlight TL3 and the hot spot is roughly the same diameter and color, but the TL3 hotspot is much smoother. Throw should be in more or less the same ballpark. I ran the light for about 2 minutes and the bulb holder and reflector and lens did get warm, but didn't seem in danger of melting. Do I need a longer test? Perhaps slightly worrisome, the spring contact at the tail end of the flashlight also got warm. I could feel this through the plastic as the light was running, but couldn't reach in far enough afterwards to actually touch the spring.
This light should be brighter than most 2xCR123 lights and have more throw because of its bigger reflector. The big reflector makes up for the not-so-precise filament placement of a PR bulb, and the bulbs are pretty cheap compared to the exotic bi-pin bulbs or lamp-reflector assemblies in higher-class flashaholic lights. Changing batteries using the taped "stick" approach is a bit of a chore, but of course you can always make up a spare "stick" in advance.
What we have is a light that's not pocketable but is still fairly compact (much smaller than a 2C Mag), is cheap ($3 host light, $3 in batteries, $1.29 bulb). It's not so great for everyday use but should make an excellent glovebox light (bright, long throw, lithium powered for shelf life and cold weather, reasonable runtime of maybe 90 minutes). This is what I'd put in my car if I didn't already have a PT Surge there.
I'd wanted to do this mod for a while and am glad I finally got around to it.
The cardboard stuff is pretty sloppy. It's hard to get it to wrap smoothly, especially the cup holders, which had pre-formed creases. But it does the job. Just to reduce the slop a bit, instead of leaving the three 123 cells loose, I made a "battery stick" by taping the cells with a lengthwise piece of packing tape. Swapped out the PR4 bulb for the KPR118 and viola.
Output is only slightly less than my Streamlight TL3 and the hot spot is roughly the same diameter and color, but the TL3 hotspot is much smoother. Throw should be in more or less the same ballpark. I ran the light for about 2 minutes and the bulb holder and reflector and lens did get warm, but didn't seem in danger of melting. Do I need a longer test? Perhaps slightly worrisome, the spring contact at the tail end of the flashlight also got warm. I could feel this through the plastic as the light was running, but couldn't reach in far enough afterwards to actually touch the spring.
This light should be brighter than most 2xCR123 lights and have more throw because of its bigger reflector. The big reflector makes up for the not-so-precise filament placement of a PR bulb, and the bulbs are pretty cheap compared to the exotic bi-pin bulbs or lamp-reflector assemblies in higher-class flashaholic lights. Changing batteries using the taped "stick" approach is a bit of a chore, but of course you can always make up a spare "stick" in advance.
What we have is a light that's not pocketable but is still fairly compact (much smaller than a 2C Mag), is cheap ($3 host light, $3 in batteries, $1.29 bulb). It's not so great for everyday use but should make an excellent glovebox light (bright, long throw, lithium powered for shelf life and cold weather, reasonable runtime of maybe 90 minutes). This is what I'd put in my car if I didn't already have a PT Surge there.
I'd wanted to do this mod for a while and am glad I finally got around to it.
