homemade running headlight.

[ifor powell]

This is my new homemade headlight for running with.

2 XPG r5s wired in parallel. Carclo 10417 optics.

Custom linear driver. 7 levels 50ma - 2000ma user settable levels. Thermal protection. Based off this thread

14500 Li-Ion cell. 100g all up.

It is a replacement for my 160g mce headlight. The aim was to get the weight down to 100g while still having 500+ lumen available. Also to get over an hour of runtime with 200+ lumen. I am very pleased with it.

The smaller 14500 instead of the 18650 cell is a major weight saving and is very stable on the head with just the Velcro attachment to the headband. The old 18650 on the mce had noticeable momentum when you turned your head quickly.

The integration of the driver into the head also saves weight and means I have been able to add thermal protection. The driver firmware can be updated via a serial link so the fact that it's sealed in is not such an issue.

The carclo optics although the tightest they do at this size are actually wider than I have on the mce light but the throw is similar with the xpg's extra lumens making up for the wider beam. The fact there is a gradual drop-off helps a lot when running where I find a sharp cut-off distracting.

In use on roads and in fields I was happy just using 250ma and 500ma. For quicker decents then the 1000ma or more may be usfull. I may well use it for biking with a 18650 cell in which case the higher levels may get some use.

With 14500 cell regulation is good at 1000ma for 38 minutes. 500ma for 80 minutes.

With an 18650 cell 1500ma is well regulated and the runtimes considerably extended and should be similar to those obtained by the mce light.

Finaly a couple of beamshots at 1000ma f4 6 seconds daylight WB.

This will probobly be my last light weight homemade untill the led technology jumps on some more. I would have a hard time getting it any lighter with just my simple tools. I have a twin to this I am finishing off which my brother will get for xmas, he will put it to use doing ski mountanearing races as well as bikeing and running.

More pictures here.

 

[Jagge]

Excellent light. With belt pack the head part is even lighter and you use it at max mode for hours if you like. This shows how poor most/all commercial headlamps are from trail runner's perspective.

 

[davidt1]

Hats off to you! Great skill.

 

[Huz]

Awesome. I would make one myself if it could be waterproof. Any thoughts on how to do this?

 

[ifor powell]

Well I don't try to make my lights fully waterproof. None of the lights I have made have been totaly waterproof but they have never stoped working becase of the rain and I have been out in some fairly serious rain with them. The worst I have had is misting up between the optics and the front cover.

This light is probobly better then my other lights as far as waterproofing gose. I was fairly liberal with the glue on the seams and have glued the wire entry point well. It's only the 2 pin female socket underneath that lets it down but that lets me update the software if I find any issues and I have added a fair few features over the old version so want to keep that option avalible. The switch is not much to look at but it is IP67 rated, I have not had any trouble with it in other aplications so far.

There is not much skill involved apart from doing my own software for the driver. The construction is just sawing and filling aluminium section and glueing it together apropriatly for the main frame. The driver cover is 0.5mm sheet cut and folded and glued like cardboard. No skill needed just lots of time...

As you say Jagge it just shows how poor the comercial lights are. Component wise I have nothing expensive here probobly <$15 worth. The most expensive bit is the headband which I get from a £5 light and throw away the light head. Making a comfortable headband is tricky, so this is a good easy alternative.

 

[Genes]

The controller doesn't look like an Atmel. Is it a PIC?

 

[ifor powell]

It is an Atmel a Tiny85. The picture was taken during construction when I just had another device in for sizing perposes.

As the board had to be realy small I could not put the pins in to have the ISP programing in place so was initaly taking the chip in and out of the socket to program it. I have since found a realy nice little bootloader so I can program it over a one wire serial link.

I found a bug with the thermal code when out with it last night. When the tempreture got below zero my code was broken and I got all sorts of flashing sequences as it got confused. Good job I found it before giving one to my brother as he will be using it in the alps for night skiing so will get it well cold. The fact that it still got to below zero when running with it at 500ma showes that you don't need much area for cooling with good airflow, as the tempreture was only anout -2.

 

[senorsam21]

That is really sweet powell!
I need to get out my old electronics book from high school and see if I can put on of those together.

 

[wacomme]

Wonderful headlamp. I wish I had the skill to make one.

So, since I don't have the skill, what's the best available running headlamp available today?

Thanks.

 

[TorchBoy]

Carclo 10417 optics.

I see that's "Tight, narrow". From your beam shots that looks quite a nice balance if there's nothing close in front of you.

Also to get over an hour of runtime with 200+ lumen.

Ha ha.

Nice work.

 

[ifor powell]

The carclo optics are not realy very narrow at all but they are very small and for running I don't like somthing too norow with too much contrast, I find the bright hotspot makes everything else seem darker. I like to have enough spill to be able to see a map / read without getting the hotspot directly on the paper which just blinds you.

Here is the light at 500ma and an led upgraded Apex on high.
Not taken at the same time but I belive the same settings.

 

[TorchBoy]

The carclo optics are not realy very narrow at all

Have you tried them with an XP-E? From other posts and beam shots I've seen they're narrower and throw better with XP-E.

Not taken at the same time but I belive the same settings.

Even if the settings aren't quite the same the pics show the different profiles quite nicely. Your DIY headlamp has a smoother beam with more spill - much nicer for general use than a hard spot.