P7 headlamp experiment

Jagge

Newly Enlightened
Joined
Jun 17, 2008
Messages
87
I have been doing some orienteering headlamp experiments with a DX P7 flashlight. Just out of curiosty. I post here something, maybe someone gets some ideas of it.

At first I replaced battery with a piece of wood with wires to be able to use external nimh battery pack. A lot like in this thread
And mounted it on my old orinteering headlamp band I haven't used for years and did some test runs.

image1.jpeg


Then I went on, cut flashlight in half, replaced controller with KD 2.8A board to be able to use full power, glued some additional cooling elemets, soldered new wires to LED and made a belt style 5Ah li-ion battery pack (KD 5Ah D cell) for it and put some tape here and there.

image2.jpeg


Here it is by my main headlamp lupine wilma.

image3.jpeg


One mode, on/off. It stays a bit over 1 h in regulation and after 80 minutes it starts to fade - long enough for most night orienteering races. Weight 390 g with external li-ion battery. It gives about the same amount of light as 830 lumen rated wilma (but I guess both are about 600-650 lumens). I don't have beam shots, but there is beam shots of the same flashlight in other threads. This may be a bit brighter because I use 2.8A board istead of the original board.

It's about as ugly a headlamp can be, its even more ugly in real life. But it's just an experiment and it works surprisingly well.
 
Very interesting, and I like how it looks!!!! :thumbsup:

Do you have a link to the KD driver that you used? I have some DX P7 flashlights that I would like to modify, so that they are brighter :twothumbs
 
Very interesting, and I like how it looks!!!! :thumbsup:

Do you have a link to the KD driver that you used? I have some DX P7 flashlights that I would like to modify, so that they are brighter :twothumbs

Unless you use a Li-ion D cell or multiple 18650s in parallel, the driver won't make them brighter.
 
Any close-ups of the light?

Let's see, I might take some. But there is nothing intresting really, just the basic idea, the est you can imegine and make much better by yourself. The back of the light is made out of a bottom of a beer can, I just left a hole there for wires. Back is painted black with permanent marker pen. Glued together with Arctic alumina adhesive.

You can use any driver you want as long as you can make it fit inside the lamp and you have suitable battery for it and your led. This one works fine with D li-ion or 4.8V nimh. 2x3xnimh (eneloop) 3.6V couldn't keep the voltage high enough.
 
c2.jpeg

c1.jpeg


As you can see I am experimenting with foil to get some additional light for map reading. Good use for some waste lumens originally hitting black rubber/aluminium and not coming out from the lamp at all.

Wires to the led goes outside the body - I originally planned to not put driver inside and put these wires wiring, just to make head part as light possible. But I changed my mid later didn't bother to put new wires. I put an tiny cooling element at the bottom too as you can see.


c4.jpeg


Re-used the original switch of the 20W halogen. Hole for wires, diver is inside and wires to both led and batteries uses the same hole. So there is ni wires inside going to led, old battery space is used just as a box for the driver. Driver is glued with AA to the top, just under the additional cooling element. As you can see it just dirty taping and it looks ugly. Maybe could use here some black heat shrink and better folio arrangement (or some reflective paint instead?).

wilma_p7.jpeg


Left: 830 lumen rated Lupine Wilma at max
Right: modified P7 head lamp.

I guess Wilma possibly gives a slightly more light, but difficult to say how much because the beam is different. The beam pattern of the P7 light is quite good for running in forest, beam pattern quite similar to old 20W orienteering halogens, it's just a lot brighter.
 
Last edited:
Unless you use a Li-ion D cell or multiple 18650s in parallel, the driver won't make them brighter.

Thanks for the information, and thanks too to Jagge, as I did not think about it before... :p ;)
 
Good job Jagge. Looks like the beems realy good for night O, you need a good bit of spill and the P7 looks to do a good job for that, definatly preferable to the Wilma and a lot cheaper...

Ifor
 
Ifor, looks like you are using same Silva frame in your light as I do.

Right, any flashlight will not do. Luckily it's difficult to make a small flashlight with a lot of throw using P7 so some of those new flashlights ended up just fine for this purpose. It would be nice to compare how much better Lupine's new P7 light Tesla is than this one.
 
beamshot2.jpeg

(Photo by JHJHJH)

Updates. I replaced all wires to new better ones and also squeezed an extra board to get some modes. Now there is ~200mA (low), 1A (med), 2.8A (high) and 3.8A (turbo). I also stopped using li-ion battery mainly for safety reasons, I use 8 x AA nimh (4.8V) instead. My next move will be swapping the LED to D bin one.
wilma_p7dbin_mica20whalogen.jpeg


Swap is done, here's beam comparison. From left: Lupine Wilma 830lumen, DIY P7, 20W halogen. Just compare this to the previous beam shot, it is a lot brighter now.
 
Last edited:
I'm thinking about making similar (if not the same) night orienteering lamp.

Could you Jagge give some status report on how your lamp has been working and if you have made any adjustments after your latest post?
 
Could you Jagge give some status report on how your lamp has been working and if you have made any adjustments after your latest post?

No changes. But I'll take away the big cooling element because it's not needed and I will not drive it over 2.8A because I have no use for extra 200 lumens. I hae been thingking how to make it better, and the best candidate is changing retro 80' headband to something lighter. if I use lighter headband instead of this plastic one and take away the cooler head part will get a lot 50g lighter. I know there is at elas one almost 1:1 copy of this headlamp.

You may have already red this but here is some info about headlamps I made soon after this one:
http://www.candlepowerforums.com/vb/showthread.php?t=212401

This MTE flashlight based headlamp's beam is more nice (reflector is designed for P7) and more powerful beam but slightly it a bit more narrow. Drop in based lamp is more lightweight and has wider beam.

Here's headlampcam video of me jogging in a nearby park with this headlamp at 2.8A:
http://www.youtube.com/watch?v=56_NRiX2udQ

I know this 800 lumens headlamp is nothing and lots of guys are running with 1500 lumen led / 35W hid headlamps. But some of but those guys are also ~31 min 10k runners, so I guess 800 lumens is enough for a crappy runner like me...
 
Nice. A soft headband could be much better also regarding packing the lamp to a bag, because it takes much less space...

I've always orienteered with a 20W halogen (no idea what the lumen -rate is, 300?), so 800 should be really good for me. We have two Lupine Wilmas owned by my club, but I've never tested one myself.

1500 plus lumen lamps are (in my opinion) getting too bright and reading map is getting more difficult because the paper and plastic cover reflect the light right to your face... But I guess the extra power makes the orienteering easier.

Could you show me precisely what components and where from I should buy to get somewhat similar lamp to your 800 lumens lamp?
I've read about different lamps and I know something about voltages and currents, but I have simply NO idea whatsoever where to buy this stuff.

+My dad is an electricity engineer and interested in headlamps, so he'll help me build the "final product".

If you're interested and you have some time to help me (or if you know someone else who is willing to help), just send me e-mail: tuomas.metsala#€gmail.com (and replace the #€ with @ ofcourse).
 
Top