how to build a headlamp??

Please excuse the jongy newbness of my query...but I figured ya'll know a hell of a lot more than me....

First off, I want to build a headlamp. I don't know a thing about electronics or the terminology used on this site, but this is what I need it for...

-Dog mushing in AK.
-winter camping in AK.
-needs to be a headlamp
-needs to be about 500+ lumens
-needs spot capacity out to 100 meters
-flood capacity would be nice
-needs to run off 4 'D'cell alkaline or lithium batteries (6 volts) (there are no electric outlets on the iditarod trial) I will ship batteries to myself.
-needs to have a battery life of at least 50% brightness for 15+ hours
-needs 'arctic cord' to withstand -40 temps.

I've seen the lupine systems tesla and wilma lights and they look exactly what I'm looking for...except for price and battery life. Is it possible for me to build a headlamp like the one described above, or like the wilma or tesla for ~$100?? What parts do I need to buy? Where do I get the parts? Is there a tutorial for piecing it all together?? What tools do I need?

ps. I have the brunton L3 and the PT Apex arctic. Is there an easy conversion I can do to either to increase light output??

thanks in advance!!

you should check out the magicshine "bike" light
from dx or geomangear and get the head strap for it

its like 100bux or so

I added a p4 emitter to my L3 but its not WAAAYYY brighter
just a little bit and has a better tint.

or build one from scratch- check the bike forums here and
MTBR and have some fun!

ohh and
:welcome::welcome::welcome:

lots to learn here!

You're describing a Magicshine (Tesla copy) with a do-it-yourself cord upgrade and your own battery pack.

Sounds like you are looking for a top-end headlamp. It's my opinion that everything on the market is either underpowered or too bulky for use when running and jumping around.

I made my own and it may give you some ideas about what can be made if you put the time and money in.

https://www.candlepowerforums.com/posts/3074772
https://www.candlepowerforums.com/threads/233854

It has a 200m spot and separate flood. I have two modes of flood, approx 70lm low and 400lm high. The 400 lm level is good for me running through bush but you may want more since mushing would be much faster.

My flood comes from two Cree XP-G LEDs which can be driven up to 1.5A each to give around 900lm.

How long it lasts all depends on how much battery you are willing to carry. Are you planning to carry the battery on your head or in a backpack/pocket/belt at the end of a cable?


If you make your own light, you will almost certainly want to use XP-Gs for broad to medium tightness beams.

For a really tight spot beam the best is an aspheric lens in front of an XR-E.

Of course the XP-Gs make for bad spot beams and the XR-E is not as efficient or compact as the XP-G. For this reason I use both, rather than make compromises in the beam quality.

I hope this gives you somewhere to start in your thinking. Reading a lot of other threads in the LED and Homemade sctions will help you too.

500 lumens for 15 hours is a tall order, especially from alkaline batteries. It may be possible with lithium D's (we're talking about the 3.7v D's, the ones that cost $15 each right?), I don't know. The Magicshine headlamp might be a good starting point, but it's max input voltage is 8.4v, which could limit your battery choices.


Here's a decent 4D battery pack that might work for you:

http://www.bhphotovideo.com/c/product/424847-REG/Pelican_2660_301_110_Extended_Duty_4_D_.html

500 lm for 15 hours needs about 75Wh worth of cells. This assumes 100lm/W. Depending of course on the number and type of LEDs and the efficiency of the driver, this is probably possible.

A D lithium Ion cell will give you about 18Wh, so 4 cells would give 72Wh. That's pretty close.

10 cheap 18650s could be had for under $50 at DX. They would probably give almost 90Wh.

smthgfshy said:

-needs to have a battery life of at least 50% brightness for 15+ hours

Click to expand...

However, 250 lumens for 15 hours as the OP might have been suggesting is much more realistic. You could achieve that with with a 4 18650 cell li-ion pack and 2 XP-G's for instance.

Questions: Why does it have to use D cell batteries and what is the PT Apex Arctic?