ambientmind
Enlightened
- Joined
- May 8, 2007
- Messages
- 465
I built this light to take with me while camping, I needed something really bright with lots of throw to light up the forest around me to check for whatever critters may be around:candle:, mainly bears. Hence the name, The Bear Light. It started off as a 2D Pewter Maglite which I bored out to accomodate 8AA NiMH batteries with a brake hone :sick2: which took forever. Then I made my own heatsink to accommodate 4 cree Q5 WC out of copper and aluminum. I know I know, I isolated the metals so they dont react with eachother.:duh2: It is a copper surface with an aluminum core about 3/8" thick, I thought the copper might help with heat transfer. I also made my own battery holder out of copper, stainless and ABS plastic that bypasses the tailspring and has a direct negative path to the drivers for less resistance. It ends up being two series sets of 4 NiMh in parallel for capacity and a total of 4.8V to keep the drivers in full regulation. Each LED gets its own driver, I used the 1.4A 7135 based boards from DX, four in all. Since the drivers are sucking about 6A from the batteries
, I took the stock switch apart, polished all the contacts and used Deoxit on all contact points. So far, its held up great with no issues after about 4 hours of total use. I used an optic from DX that actually fits really well and makes a great pattern. The hotspot is really nice, with no rings around it. I also covered the surface of the heatsink with "white" glow powder from Glow Inc mixed with epoxy 330. It glows more of a cool blue color, but still looks neat and provides a surprising amount of light when it glows. Topping it all off is UCL glass from Kai and one of Kiu's bezels. Best of all, this thing is BRIGHT! Compared to my P7 @3.3A, its slightly brighter when doing a ceiling bounce test. I figure it should be about 921 lumens out the front (Q5 @ 1.4A is~288Lm. 288*4=1152 bulb lumens, 1152*.8=921 lumens. The optics are 85-90% efficient+the UCL is around 97% efficient so being on the safe side, 80% total effeciency seems about right?). It gets pretty warm after continuous use, but never too hot to hold. There actually is some heat coming out the front which surprised me, if you press it up against a black plastic garbage bag, it actually heats and softens the plastic but doesnt burn through it. I may end up changing the LEDs out for R2 WG bin, just for some better color. No beamshots yet, but soon. All in all it took me about 10 hours to make but I had a lot of fun making it, well except for boring it out...but the rest was fun!:thumbsup:
Update: :devil:
I finally got to take beamshots today, I put it up against a few lights...
All measurements are from Google maps. Camera was a Canon EOS 20D on a tripod with remote shutter release, white balance set to daylight, ISO 200, 2 second exposure. The first set is at f4, second at f4.5 (not sure why I changed it)
First up, its 230ft to the left palm tree, and 44ft to the corner of the fence.
Control Shot:
Fenix TK10
Mag P7 @3.3A
24w HID
Bear Light
Next, its 221 ft to the tree in the center, 74ft to the tree just to the right of center, and 47ft to the gate on the wooden fence. More lights this time.
Control
NovaTac 120P on high
Fenix TK10
TLS head with R2 WG
Raidfire Spear
P7 Mag
24w HID
Bear Light
, I took the stock switch apart, polished all the contacts and used Deoxit on all contact points. So far, its held up great with no issues after about 4 hours of total use. I used an optic from DX that actually fits really well and makes a great pattern. The hotspot is really nice, with no rings around it. I also covered the surface of the heatsink with "white" glow powder from Glow Inc mixed with epoxy 330. It glows more of a cool blue color, but still looks neat and provides a surprising amount of light when it glows. Topping it all off is UCL glass from Kai and one of Kiu's bezels. Best of all, this thing is BRIGHT! Compared to my P7 @3.3A, its slightly brighter when doing a ceiling bounce test. I figure it should be about 921 lumens out the front (Q5 @ 1.4A is~288Lm. 288*4=1152 bulb lumens, 1152*.8=921 lumens. The optics are 85-90% efficient+the UCL is around 97% efficient so being on the safe side, 80% total effeciency seems about right?). It gets pretty warm after continuous use, but never too hot to hold. There actually is some heat coming out the front which surprised me, if you press it up against a black plastic garbage bag, it actually heats and softens the plastic but doesnt burn through it. I may end up changing the LEDs out for R2 WG bin, just for some better color. No beamshots yet, but soon. All in all it took me about 10 hours to make but I had a lot of fun making it, well except for boring it out...but the rest was fun!:thumbsup:
Update: :devil:
I finally got to take beamshots today, I put it up against a few lights...
All measurements are from Google maps. Camera was a Canon EOS 20D on a tripod with remote shutter release, white balance set to daylight, ISO 200, 2 second exposure. The first set is at f4, second at f4.5 (not sure why I changed it)
First up, its 230ft to the left palm tree, and 44ft to the corner of the fence.
Control Shot:
Fenix TK10
Mag P7 @3.3A
24w HID
Bear Light
Next, its 221 ft to the tree in the center, 74ft to the tree just to the right of center, and 47ft to the gate on the wooden fence. More lights this time.
Control
NovaTac 120P on high
Fenix TK10
TLS head with R2 WG
Raidfire Spear
P7 Mag
24w HID
Bear Light
Last edited:
